Title of Invention

COMPOSITIONS AND METHODS FOR ENHANCED MUCOSAL DELIVERY OF Y2 RECEPTOR -BINDING PEPTIDES AND METHODS FOR TREATING AND PREVENTING OBESITY

Abstract Pharmaceutical compositions and methods are described comprising at least one peptide YY compound and one or more intranasal delivery-enhancing agents for enhanced nasal mucosal delivery of the peptide YY, for treating a variety of diseases and conditions in mammalian subjects, including obesity. In one aspect, the intranasal delivery formulations and methods provide enhanced delivery of peptide YY to the blood plasma or centra] nervous system (CNS) tissue or fluid, for example, by yielding a peak concentration (Cmax) of the peptide YY in the blood plasma or CNS tissue or fluid of the subject that is 20% or greater compared to a peak concentration of the peptide YY in the blood plasma or CNS tissue or fluid of the subject following administration to the subject of a same concentration or dose of the peptide YY to the subject by subcutaneous injection.
Full Text COMPOSITIONS AND METHODS FOR ENHANCED MUCOSAL DELIVERY
OF Y2 RECEPTOR-BINDING PEPTIDES AND METHODS FOR TREATING AND
PREVENTING OBESITY
Background of the Invention
Obesity and its associated disorders are common and very serious public health
problems in the United States and throughout the world. Upper body obesity is the
strongest risk factor known for type-2 diabetes mellitus, and is a strong risk factor for
cardiovascular disease. Obesity is a recognized risk factor for hypertension,
arteriosclerosis, congestive heart failure, stroke, gallbladder disease, osteoarthritis, sleep
apnea, reproductive disorders such as polycystic ovarian syndrome, cancers of the breast,
prostate, and colon, and increased incidence of complications of general anesthesia. It
reduces life-span and carries a serious risk of co-morbidities above, as well disorders such
as infections, varicose veins, acanthosis nigricans, eczema, exercise intolerance, insulin
resistance, hypertension hypercholesterolemia, cholelithiasis, orthopedic injury, and
thromboembolic disease. Obesity is also a risk factor for the group of conditions called
insulin resistance syndrome, or "Syndrome X."
It has been shown that certain peptides that bind to the Y2 receptor when
administered peripherally to a mammal induce weight loss. The Y2 receptor-binding
peptides are neuropeptides that bind to the Y2 receptor. Neuropeptides are small peptides
originating from large precursor proteins synthesized by peptidergic neurons and
endocrine/paracrine cells. Often the precursors contain multiple biologically active
peptides. There is great diversity of neuropeptides in the brain caused by alternative
splicing of primary gene transcripts and differential precursor processing. The neuropeptide
receptors serve to discriminate between ligands and to activate the appropriate signals.
These Y2 receptor-binding peptides belong to a family of peptides including peptide YY
(PYY), neuropeptide Y (NPY) and pancreatic peptide (PP).
NPY is a 36-amino acid peptide and is the most abundant neuropeptide to be
identified in mammalian brain. NPY is an important regulator in both the central and
peripheral nervous systems and influences a diverse range of physiological parameters,
including effects on psychomotor activity, food intake, central endocrine secretion, and
vasoactivity in the cardiovascular system. High concentrations of NPY are found in
the sympathetic nerves supplying the coronary, cerebral, and renal vasculature and have
contributed to vasoconstriction. NPY binding sites have been identified in a variety of tissues,
including spleen, intestinal membranes, brain, aortic smooth muscle, kidney, testis, and
placenta.
Neuropeptide Y (NPY) receptor pharmacology is currently defined by structure activity
relationships within the pancreatic polypeptide family. This family includes NPY, which is
synthesized primarily in neurons; PYY, which is synthesized primarily by endocrine cells in
the gut; and PP, which is synthesized primarily by endocrine cells in the pancreas. These
approximately 36 amino acid peptides have a compact helical structure involving a "PP-fold"
in the middle of the peptide. Specific features include a polyproline helix in residues 1
through 8, a .beta.-turn in residues 9 through 14, an .alpha.-helix in residues 15 through 30,
an outward-projecting C-terminus in residues 30 through 36, and a carboxyl terminal amide,
which appears to be critical for biological activity. The peptides have been used to define at
least five receptor subtypes known as Yl, Y2, Y3, Y4 and Y5. Yl receptor recognition by
NPY involves both N- and C-terminal regions of the peptide; exchange of Gln34 with Pro34 is
fairly well tolerated. Y2 receptor recognition by NPY depends primarily upon the four C-
terminal residues of the peptide (Arg33 - Gln34 -Arg35 - Tyr36 -NH2) preceded by an
amphipathic alpha.-helix ; exchange of Gln34 with Pro34 is not well tolerated. One of the key
pharmacological features which distinguish Yl and Y2 is the fact that the Y2 receptor (and
not the Y1 receptor) has high affinity for the NPY peptide carboxyl-terminal fragment NPY-
(13-36) and the PYY fragment PYY22-36.
It has been shown that a 36 amino acid peptide called Peptide YY(l-36) [PYY(l-36)]
[YPIKPEAPGEDASPEELNRYYASLRHYLNLVTRQRY, SEQ ID NO.: 1]. when
administered peripherally by injection to an individual produces weight loss and thus can be
used as a drug to treat obesity and related diseases, Morley, J. Neuropsychobiology 21:22-30
(1989). It was later found that to produce this effect PYY bound to a Y2 receptor, and the
binding of a Y2 agonist to the Y2 receptor caused a decrease in the ingestion of carbohydrate,
protein and meal size, Leibowitz, S.F. et al. Peptides, 12: 1251-1260 (1991). An alternate
molecular form of PYY is PYY(3-36) IKPEAPGEDASPEELNRYYASLRHYLNLVTRQRY
[SEQ ID NO.: 2], Eberlein, Eysselein et al. Peptides 10: 797-803, 1989). This fragment
constitutes approximately 40% of total PYY-like immunoreactivity in human and canine
intestinal extracts and about 36% of total plasma PYY immunoreactivity in a fasting state to
slightly over 50% following a meal. It is apparently a dipeptidyl peptidase-IV (DPP4)
cleavage product of PYY. PYY3-36 is reportedly a selective ligand at the Y2 and Y5
receptors, which appear pharmacologically unique in preferring N-terminally truncated (i.e.
C-terminal fragments of) NPY analogs. It has also been shown that a PYY fragment having
only residues 22-36 will still bind to the Y2 receptor. However, if any of the carboxyl
terminus of the peptide is cleaved, the peptide looses its ability to bind to the Y2 receptor.
Hence a PYY agonist is a peptide, which has a partial sequence of full-length PYY and is
able to bind to a Y2 receptor in the arcuate nucleus of the hypothalamus. Hereinafter the
term PYY refers to full-length PYY and any fragment of PYY that binds to a Y2 receptor.
It is known that PYY and PYY3-36 can be administered by intravenous infusion or
injection to treat life-threatening hypotension as encountered in shock, especially that caused
by endotoxins (US Patent 4,839,343), to inhibit proliferation of pancreatic tumors in
mammals by perfusion, parenteral, intravenous, or subcutaneous administration, and by
implantation (US Patent 5,574,010) and to treat obesity (Morley, J. Neuropsychobiology
21:22-30 (1989) and US Patent Application 20020141985). It is also claimed that PYY can
be administered by parenteral, oral, nasal, rectal and topical routes to domesticated animals or
humans in an amount effective to increase weight gain of said subject by enhancing
gastrointestinal absorption of a sodium-dependent cotransported nutrient (US Patent
5,912,227). However, for the treatment of obesity and related diseases, including diabetes,
the mode of administration has been limited to intravenous IV infusion with no effective
formulations optimized for alternative administration of PYY3-36. None of these prior art
teachings provide formulations that contain PYY or PYY(3-36) combined with excipients
designed to enhance mucosal (i.e., nasal, buccal, oral) delivery nor do they teach the value of
endotoxin-free Y2-receptor binding peptide formulations for non-infused administration.
Thus, there is a need to develop formulations and methods for administering PYY3-36.
Summary of the Invention
The present invention fulfills the foregoing needs and satisfies additional objects and
advantages by providing novel, effective methods and compositions for mucosal, especially
intranasal, delivery of a Y2 receptor-binding peptide such as PYY, Pancreatic Peptide (PP)
and NPY, to treat obesity, induce satiety in an individual and to promote weight-loss in an
individual and prevent or cure diabetes. In certain aspects of the invention, the Y2 receptor-
binding peptide is delivered in formulations to the intranasal mucosa so as to be able to
increase the concentration of the Y2 receptor-binding peptide by at least 5 pmol, preferably
by at least 10 pmol, in the blood plasma of a mammal when a dose of the formulations of the
Y2 receptor agonist is administered intranasally. Furthermore preferred formulations would
be able to raise the concentration of the Y2 receptor-binding peptide in the plasma of a
mammal by 10 pmol, preferably 20 pmol, when the Y2 receptor- binding peptide is
administered intranasally. When 150 µg is administered intranasally the preferred
formulation would be able to raise the concentration of the Y2 receptor agonist in the plasma
of the mammal by at least 40 pmol per liter of plasma. When 200 ug of the Y2 receptor-
binding peptide is administered intranasally, the formulations of the present invention induce
at least 80 pmol, per liter of plasma increase of the Y2 receptor-binding peptide.
Preferably the Y2 receptor-binding peptide is a PP, PYY or NPY peptide and the
mammal is a human. In a most preferred embodiment the Y2 receptor-binding peptide is a
PYY peptide, preferably PYY(3-36) and the mammal is human.
The present invention is also related to a Y2 receptor-binding peptide formulation that
is able to raise the concentration of the Y2 receptor-binding peptide in the blood plasma of a
mammal by at least 5 pM when a dose containing at least 50 ug of the Y2 receptor-binding
peptide is administered to the mammal.
The present invention is also related to a Y2 receptor-binding peptide formulation that
is able to raise the concentration of the Y2 receptor-binding peptide in the blood-plasma of a
mammal by at least 20 pM when a dose containing at least 100 µg of the Y2 receptor-binding
peptide is administered to the mammal.
The present invention is also related to a Y2 receptor-binding peptide formulation that
when administered intranasally to a mammal is able to raise the concentration of the Y2
receptor-binding peptide in blood plasma of the mammal by at least 30 pM when a dose
containing at least 150 µg of the Y2 receptor-binding peptide is administered. Preferably the
mammal is a human.
The present invention is also related to a Y2 receptor-binding peptide formulation that
when administered intranasally to a mammal is able to raise the concentration of the Y2
receptor-binding peptide by at least 60 pM when a dose containing at least 200 µg is
administered to the mammal. Preferably the mammal is a human.
The present invention is also directed to an intranasal formulation of a Y2 receptor-
agonist that is substantially free of proteins or polypeptides that stabilize the formulation. In
particular, the preferred formulation is free of such proteins as albumin, and collagen-derived
proteins such as gelatin.
In other aspects of the present invention a transmucosal Y2 receptor-binding peptide
formulation is comprised of a Y2 receptor-binding peptide, water and a solubilizing agent
having a pH of 3-6.5. In a preferred embodiment, the solubilization agent is a cyclodextrin.
In another embodiment of the present invention a transmucosal Y2 receptor-binding
peptide formulation is comprised of a Y2 receptor-binding peptide, water, a solubilizing
agent, preferably a cyclodextrin, and at least one polyol, preferably 2 polyols. In alternate
embodiments the formulation may contain one or all of the following: a chelating agent, a
surface-acting agent and a buffering agent.
In another embodiment of the present invention the formulation is comprised of a Y2
receptor-binding peptide, water, chelating agent and a solubilization agent.
In another embodiment of the present invention the formulation is comprised of a Y2
receptor-binding peptide, water and a chelating agent having a pH of 3-6.5.
In another embodiment of the present invention the formulation is comprised of a Y2
receptor-binding peptide, water, chelating agent and at least one polyol, preferably two
polyols. Additional embodiments may include one or more of the following: a surface-active
agent, a solubilizing agent and a buffering agent.
In another embodiment of the present invention the formulation is comprised of a Y2
receptor-binding peptide, water, and at least two polyols, such as lactose and sorbitol.
Additional agents, which can be added to the formulation, include, but are not limited to, a
solubilization agent, a chelating agent, one or more buffering agents and a surface-acting
agent.
The enhancement of intranasal delivery of a Y2 receptor-binding peptide agonist
according to the methods and compositions of the invention allows for the effective
pharmaceutical use of these agents to treat a variety of diseases and conditions in mammalian
subjects.
The present invention fills this need by providing for a liquid or dehydrated Y2
receptor-binding peptide formulation wherein the formulation is substantially free of a
stabilizer that is a polypeptide or a protein. The liquid PYY formulation is comprised of
water, PYY and at least one of the following additives selected from the group consisting of
polyols, surface-active agents, solubilizing agents and chelating agents. The pH of the
formulation is preferably 3 to about 7.0, referably 4.5 to about 6.0, most preferably about
5.0±.03.
Another embodiment of the present invention is an aqueous Y2 receptor-binding
formulation of the present invention is comprised of water, a Y2 receptor-binding peptide, a
polyol and a surface-active agent wherein the formulation has a pH of about 3 to about 6.5,
and the formulation is substantially free of a stabilizer that is a protein or polypeptide.
Another embodiment of the present invention is an aqueous Y2 receptor-binding
peptide formulation comprised of water, Y2 receptor-binding peptide, a polyol and a
solubilizing agent wherein the formulation has a pH of about 3.0 to about 6.5, and the
formulation is substantially free of a stabilizer that is a protein or polypeptide.
Another embodiment of the present invention is an aqueous Y2 receptor-binding
peptide formulation comprised of water, Y2 receptor-binding peptide, a solubilizing agent
and a surface-active agent wherein the formulation has a pH of about 3.0 to about 6.5, and the
formulation is substantially free of a stabilizer that is a protein or polypeptide.
Another embodiment of the invention is a aqueous Y2 receptor-binding peptide
formulation comprised of water, a Y2 receptor-binding peptide, a solubilizing agent, a polyol
and a surface-active agent wherein the formulation has a pH of about 3.0 to about 6.5, and the
formulation is substantially free of a stabilizer that is a protein or polypeptide.
In another aspect of the present invention, the stable aqueous formulation is
dehydrated to produce a dehydrated Y2 receptor-binding peptide formulation comprised of
Y2 receptor-binding peptide and at least one of the following additives selected from the
group consisting of polyols, surface-active agents, solubilizing agents and chelating agents,
wherein said dehydrated Y2 receptor-binding peptide formulation is substantially free of a
stabilizer that is a protein or polypeptide such as albumin, collagen or collagen-derived
protein such as gelatin. The dehydration can be achieved by various means such as
lyophilization, spray-drying, salt-induced precipitation and drying, vacuum drying, rotary
evaporation, or supercritical CO2 precipitation.
In one embodiment, the dehydrated Y2 receptor-binding peptide is comprised of Y2
receptor-binding peptide, a polyol and a solubilizing agent, wherein the formulation is
substantially free of a stabilizer that is a protein.
In another embodiment, the dehydrated Y2 receptor-binding peptide formulation is
comprised of a Y2 receptor-binding peptide, a polyol, and a surface-active agent wherein the
Y2 receptor-binding peptide formulation is substantially free of a stabilizer that is a protein or
polypeptide.
In another embodiment, the dehydrated Y2 receptor-binding peptide formulation is
comprised of a Y2 receptor-binding peptide, a surface-active agent, and a solubilizing agent
wherein the Y2 receptor-binding peptide formulation is substantially free of a stabilizer that
is a protein or polypeptide.
In another embodiment of the present invention, the dehydrated Y2 receptor-binding
peptide formulation is comprised of a Y2 receptor-binding peptide, a polyol, a surface-active
agent and a solubilizing agent wherein the Y2 receptor-binding peptide formulation is
substantially free of a stabilizer that is a protein or polypeptide.
Any solubilizing agent can be used but a preferred one is selected from the group
consisting of hydroxypropyl-b-cyclodextran, sulfobutylether-|3-cyclodextran, methyl-P-
cyclodextrin and chitosan.
Generally a polyol is selected from the group consisting of lactose, sorbitol, trehalose,
sucrose, mannose and maltose and derivatives and homologs thereof.
A satisfactory surface-active agent is selected from the group consisting of L-a-
phospharidycholine didecanoyl (DDPC), polysorbate 20 (Tween 20), polysorbate 80 (Tween
80), polyethylene glycol (PEG), cetyl alcohol, polyvinylpyrolidone (PVP), polyvinyl alcohol
(PVA), lanolin alcohol, and sorbitan monooleate.
In a preferred formulation, the Y2 receptor-binding peptide formulation is also
comprised of a chelating agent such as ethylene diamine tetraacetic acid (EDTA) or ethylene
glycol tetraacetic acid (EGTA). Also a preservative such as chlorobutanol or benzylkonium
chloride can be added to the formulation to inhibit microbial growth.
The pH is generally regulated using a buffer such as sodium citrate and citric acid,
and sodium acetate and acetic acid. An alternative buffer would be acetic acid and sodium
acetate or succinic acid and sodium hydroxide.
The preferred Y2 receptor-binding peptide is a PYY, PP or NPY peptide, preferably a
PYY(3-36) peptide.
The present invention also comprehends a formulation wherein the concentration of
the Y2 receptor-binding peptide is 0.1 - 15.0 mg/mL, preferably 1.0-2 mg/mL and the pH
of the aqueous solution is 3.0 - 6.5 preferably about 5.0 ± 0.3.
The present invention further includes Y2 receptor-binding peptide formulation
wherein the concentration of the polyol is between about 0.1% and 10% (w/v) and
additionally wherein the concentration of the polyol is in the range from about 0.1% to about
3% (w/v).
The instant invention also includes a formulation, wherein the concentration of the
surface-active agent is between about 0.00001% and about 5%(w/v), and wherein the
concentration of the surface-active agent is between about 0.0002% and about 0.1% (w/v).
The instant invention also includes a formulation, wherein the concentration of the
solubilzation agent is 1% - 10% (w/v), and wherein the concentration of the solubilizing
agent is 2% to 5% (w/v).
The finished solution can be filtered and freeze-dried, lyophilized, using methods well
known to one of ordinary skill in the art, and by following the instructions of the
manufacturer of the lyophilizing equipment. This produces a dehydrated Y2 receptor-binding
peptide formulation substantially free of a stabilizer that is a protein.
In another embodiment of the present invention, a Y2 receptor-binding peptide
formulation is comprised of an Y2 receptor-binding peptide and a pharmaceutically
acceptable carrier wherein the Y2 receptor-bind peptide formulation has at least 1%,
preferably 3% and most preferably at least 6% higher permeation in an in vitro tissue
permeation assay than a control formulation consisting of water, sodium chloride, a buffer
and the Y2 receptor-binding peptide, as determined by the transepithelial electrical resistance
assay shown in Examples 2 & 7. In a preferred embodiment, the Y2 receptor-binding
formulation is further comprised of at least one excipient selected from the group consisting
of a surface-active agent, a solubilization agent, a polyol, and a chelating agent. Preferably
the Y2 receptor-binding peptide is a PYY peptide, an NPY peptide or a PP peptide.
In another embodiment of the present invention a Y2 receptor-binding petide
formulation is provided that is capable of raising the concentration of the Y2 receptor-binding
peptide in the plasma of a mammal by at least 5 preferably 10,20 40, 60, 80 or more pmoles
per liter of plasma when 100 µL of the formulation is administered intranasally to said
mammal.
In exemplary embodiments, the enhanced delivery methods and compositions of the
present invention provide for therapeutically effective mucosal delivery of the Y2 receptor-
binding peptide agonist for prevention or treatment of obesity and eating disorders in
mammalian subjects. In one aspect of the invention, pharmaceutical formulations suitable for
intranasal administration are provided that comprise a therapeutically effective amount of a
Y2 receptor-binding peptide and one or more intranasal delivery-enhancing agents as
described herein, which formulations are effective in a nasal mucosal delivery method of the
invention to prevent the onset or progression of obesity or eating disorders in a mammalian
subject. Nasal mucosal delivery of a therapeutically effective amount of a Y2 receptor-
binding peptide agonist and one or more intranasal delivery-enhancing agents yields elevated
therapeutic levels of the Y2 receptor-binding peptide agonist in the subject and inhibits food
intake in the mammalian subject, reducing symptoms of obesity or an eating disorder.
The enhanced delivery methods and compositions of the present invention provide for
therapeutically effective mucosal delivery of a Y2 receptor-binding peptide for prevention or
treatment of a variety of diseases and conditions in mammalian subjects. Y2 receptor-
binding peptide can be administered via a variety of mucosal routes, for example by
contacting the Y2 receptor-binding peptide to a nasal mucosal epithelium, a bronchial or
pulmonary mucosal epithelium, the oral buccal surface or the oral and small intestinal
mucosal surface. In exemplary embodiments, the methods and compositions are directed to
or formulated for intranasal delivery (e.g., nasal mucosal delivery or intranasal mucosal
delivery).
In one aspect of the invention, pharmaceutical formulations suitable for intranasal
administration are provided that comprise a therapeutically effective amount of a Y2
receptor-binding peptide agonist and one or more intranasal delivery-enhancing agents as
described herein, which formulations are effective in a nasal mucosal delivery method of the
invention to prevent the onset or progression of obesity, diabetes, cancer, or malnutrition or
wasting related to cancer in a mammalian subject, or to alleviate one or more clinically well-
recognized symptoms of obesity, as well as treating Alzheimer's disease, colon carcinoma,
colon adenocarcinoma, pancreatic carcinoma, pancreatic adenocarcinoma, breast carcinoma.
In another aspect of the invention, pharmaceutical formulations and methods are
directed to administration of a Y2 receptor-binding peptide agonist in combination with
vitamin E succinate. A Y2 receptor-binding peptide agonist in combination with vitamin E
succinate may be administered to alleviate symptoms or prevent the onset or lower the
incidence or severity of cancer, for example, colon adenocarcinoma, pancreatic
adenocarcinoma, or breast cancer.
In another aspect of this invention, it was surprisingly found that the use of endotoxin-
free Y2 receptor binding peptides, for example PYY(3-36), produced increased mucosal
delivery compared to peptides in which endotoxin is not removed. The use of endotxin-free
Y2 receptor peptides in pharmaceutical formulations is thus enabled for administration by
non-infusion routes, including mucosal delivery, nasal, oral, pulmonary, vaginal, rectal and
the like.
The foregoing mucosal Y2 receptor-binding peptide formulations and preparative and
delivery methods of the invention provide improved mucosal delivery of a Y2 receptor-
binding peptide to mammalian subjects. These compositions and methods can involve
combinatorial formulation or coordinate administration of one or more Y2 receptor-binding
peptides with one or more mucosal delivery-enhancing agents. Among the mucosal delivery-
enhancing agents to be selected from to achieve these formulations and methods are (a)
solubilization agents; (b) charge modifying agents; (c) pH control agents; (d) degradative
enzyme inhibitors; (e) mucolytic or mucus clearing agents; (f) ciliostatic agents; (g)
membrane penetration-enhancing agents (e.g., (i) a surfactant, (ii) a bile salt, (ii) a
phospholipid or fatty acid additive, mixed micelle, liposome, or carrier, (iii) an alcohol, (iv)
an enamine, (v) an NO donor compound, (vi) a long-chain amphipathic molecule (vii) a small
hydrophobic penetration enhancer; (viii) sodium or a salicylic acid derivative; (ix) a glycerol
ester of acetoacetic acid (x) a cyclodextrin or beta-cyclodextrin derivative, (xi) a medium-
chain fatty acid, (xii) a chelating agent, (xiii) an amino acid or salt thereof, (xiv) an N-
acetylamino acid or salt thereof, (xv) an enzyme degradative to a selected membrane
component, (ix) an inhibitor of fatty acid synthesis, (x) an inhibitor of cholesterol synthesis;
or (xi) any combination of the membrane penetration enhancing agents of (i)-(x)); (h)
modulatory agents of epithelial junction physiology, such as nitric oxide (NO) stimulators,
chitosan, and chitosan derivatives; (i) vasodilator agents; (j) selective transport-enhancing
agents; and (k) stabilizing delivery vehicles, carriers, supports or complex-forming species
with which the Y2 receptor-binding peptide (s) is/are effectively combined, associated,
contained, encapsulated or bound to stabilize the active agent for enhanced mucosal delivery.
In various embodiments of the invention, peptide YY is combined with one, two,
three, four or more of the mucosal delivery-enhancing agents recited in (a)-(k), above. These
mucosal delivery-enhancing agents may be admixed, alone or together, with peptide YY, or
otherwise combined therewith in a pharmaceutically acceptable formulation or delivery
vehicle. Formulation of peptide YY with one or more of the mucosal delivery-enhancing
agents according to the teachings herein (optionally including any combination of two or
more mucosal delivery-enhancing agents selected from (a)-(k) above) provides for increased
bioavailability of the peptide YY following delivery thereof to a mucosal surface of a
mammalian subject.
Thus, the present invention is a method for suppressing apetite, promoting weight
loss, decreasing food intake, or treating obesity and/or diabetes in a mammal comprising
transmucosally administering a formulation comprised of a Y2 receptor-binding peptide, such
that when at 50 ug of the Y2 receptor is administered transmucosally to the mammal the
concentration of the Y2 receptor-binding peptide in the plasma of the mammal increases by at
least 5 pmol, preferably at least 10 pmol per liter of plasma. Examples of such formulations
are described above.
The present invention further provides for the use of a Y2 receptor-binding peptide
for the production of medicament for the transmucosal, administration of a Y2 receptor-
binding peptide for suppressing apetite, promoting weight loss, decreasing food intake, or
treating obesity in a mammal such that when about 50 ug of the Y2 receptor is administered
transmucosally to the mammal the concentration of the Y2 receptor-binding peptide in the
plasma of the mammal increases by at least 5 pmol per liter of plasma. When 100 µg of the
Y2 receptor-binding peptide is administered intranasally to the mammal, the concentration of
the Y2 receptor agonist increases by at least 20 pmol per liter of plasma in the mammal.
When 150 µg is administered, the concentration
A mucosally effective dose of peptide YY within the pharmaceutical formulations of
the present invention comprises, for example, between about 0.001 pmol to about 100 pmol
per kg body weight, between about 0.01 pmol to about 10 pmol per kg body weight, or
between about 0.1 pmol to about 5 pmol per kg body weight. In further exemplary
embodiments, dosage of peptide YY is between about 0.5 pmol to about 1.0 pmol per kg
body weight. In a preferred embodiment an intranasal dose will range from 50 µg to 400 µg,
preferably 100 µg to 200 µg, most preferably about 100 µg to 150 µg. The pharmaceutical
formulations of the present invention may be administered one or more times per day (for
example, before a meal), or 3 times per week or once per week for between one week and at
least 96 weeks or even for the life of the individual patient or subject. In certain
embodiments, the pharmaceutical formulations of the invention are administered one or more
times daily, two times daily, four times daily, six times daily, or eight times daily.
Intranasal delivery-enhancing agents are employed which enhance delivery of peptide
YY into or across a nasal mucosal surface. For passively absorbed drugs, the relative
contribution of paracellular and transcellular pathways to drug transport depends upon the
pKa, partition coefficient, molecular radius and charge of the drug, the pH of the luminal
environment in which the drug is delivered, and the area of the absorbing surface. The
intranasal delivery-enhancing agent of the present invention may be a pH control agent. The
pH of the pharmaceutical formulation of the present invention is a factor affecting absorption
of peptide YY via paracellular and transcellular pathways to drug transport. In one
embodiment, the pharmaceutical formulation of the present invention is pH adjusted to
between about pH 3.0 to 6.5. In a further embodiment, the pharmaceutical formulation of the
present invention is pH adjusted to between about pH 3.0 to 5.0. In a further embodiment,
the pharmaceutical formulation of the present invention is pH adjusted to between about pH
4.0 to 5.0. Generally, the pH is 5.0±0.3.
Brief Description of the Drawings
FIG. 1 shows the stability of PYY3-36 at high temperature (40° C) at various pHs from 3.0
to 7.4.
FIG. 5 shows the synergistic contributions of the various components on drug permeation.
In figure 5 EN 1 is DDPC, EN2 is methyl-b-cyclodextrin, and EX1 is EDTA.
FIG. 6 shows the PYY3-36 in the plasma of rats, the square represent a dose of 4.1 µg/kg,
the triangle represents a dose of 41 µg/kg, and the circle represent a dose of 205 µg/kg.
FIG. 7 shows dose linearity following intranasal administration PYY3-36 in rats as Cmax-
Cbas pg/mL v. dose as µg/kg.
FIG. 8 shows dose linearity following intranasal administration of PYY3-36 in rats as AUC
v. dose as µg/kg.
FIG. 9 shows the average plasma concentration of PYY v. time in minutes in three human
volunteers who were each administered 20 ug of PYY(3-36) intranasally.
FIG. 10 shows the average plasma concentration of PYY v. time in minutes in three human
volunteers who were each administered 50 µg of PYY(3-36) intranasally.
FIG. 11 shows the average plasma concentration of PYY v. time in minutes in three human
volunteers who were each administered 100 µg of PYY(3-36) intranasally.
FIG. 12 shows the average plasma concentration of PYY v. time in minutes in three human
volunteers who were each administered 150 µg of PYY3-36 intranasally.
FIG. 13 shows the average plasma concentration of PYY v. time in minutes in three human
volunteers who were each administered 200 µg of PYY(3-36) intranasally.
FIG. 14 shows PYY plasma concentration as pmol/L v. time for five groups of healthy
human volunteers who received intranasal PYY(3-36). The doses were 200 µg, 150 µg, 100
ug, 50 µg and 20 µg of PYY3-36.
FIG. 15 shows the dose linearity Cmax of PYY in pg/mL vs. dose of PYY(3-36)
administered to human volunteers.
FIG. 16 shows the dose linearity PYY mean AUC in pg/mL vs. dose of PYY(3-36)
administered to human volunteers.
FIG. 17 shows the visual analog scale (VAS) vs. dose of PYY(3-36) administered to the
human volunteers. The question was: "How hungry are you?" The lower the score the less
hungry an individual was on a 100 point scale.
FIG. 18 shows the visual analog scale (VAS) vs. dose of PYY(3-36) administered to the
human volunteers. The question was: "How much could you eat?" The lower the score the
less hungry an individual was on a 100 point scale.
FIG. 19 shows the visual analog scale (VAS) vs. dose of PYY(3-36) administered to the
human volunteers. The question was: "How full do you feel?" The lower the score the less
full an individual was on a 100 point scale.
FIG. 20 shows the per cent permeation of PYY(3-36) containing endotoxin vs. endotoxin-
free PYY(3-36).
Detailed Description of the Invention
As noted above, the present invention provides improved methods and compositions
for mucosal delivery of Y2 receptor-binding peptide to mammalian subjects for treatment or
prevention of a variety of diseases and conditions. Examples of appropriate mammalian
subjects for treatment and prophylaxis according to the methods of the invention include, but
are not restricted to, humans and non-human primates, livestock species, such as horses,
cattle, sheep, and goats, and research and domestic species, including dogs, cats, mice, rats,
guinea pigs, and rabbits.
In order to provide better understanding of the present invention, the following
definitions are provided:
Y2 RECEPTOR-BINDING PEPTIDES
The Y2 receptor-binding peptides used in the mucosal formulations of the present
invention include the pancreatic polypeptide family." as used herein, is comprised of three
naturally occurring bioactive peptide families, PP, NPY, and PYY. Examples of Y2
receptor-binding peptides and their uses are described in U.S. Patent No. 5,026,685; U.S.
Patent No. 5,574,010; U.S. Patent No. 5,604,203; U.S. Patent No. 5,696,093; U.S. Patent No.
6,046,167; Gehlert et.al, Proc Soc Exp Biol Med 218:1-22 (1998); Sheikh et al Am J
Physiol, 257:701-15(1991); Fournier et al, Mol Pharmacol 45:93-101 (1994); Kirby et al., J
Med Chem 55:4579-4586 (1995); Rist et al., EurJBiochem 247: 1019-1028 (1997); Kirby et
al, JMed Chem 35:3802-3808 (1993); Grundemar et al, Regulatory Peptides 62: 131-136
(1996); U.S. Patent No. 5,696,093 (examples of PYY agonists), U.S. Patent No. 6,046,167.
According to the present invention a Y2 receptor-binding peptide includes the free bases, acid
addition salts or metal salts, such as potassium or sodium salts or the peptides Y2 receptor-
binding peptides that have been modified by such processes as amidation, glycosylation,
acylation, sulfation, phosphorylation, acetylation and cyclization, (U.S. Patent No. 6,093,692;
and U.S. patent No. 6,225,445 and pegylation.
PEPTIDE YY AGONISTS
As used herein, "PYY" refers to PYY(l-36) in native-sequence or in variant form, as
well as derivatives, fragments, and analogs of PYY from any source, whether natural,
synthetic, or recombinant. The PYY must be comprised at least the last 15 amino acid
residues or analogoues thereof of the PYY sequence,PYY(22- 36) (SEQ ID NO: 3). Other
PYY peptides, which may be used are PYY(l-36) (SEQ ID NO: 1) PYY(3-36) SEQ ID NO:
2) PYY(4-36 )(SEQ ID NO:4) PYY(5-36) (SEQ ID NO: 5), PYY(6-36) (SEQ ID NO:6),
PYY(7-36) (SEQ ID NO:7) PYY(8-36) (SEQ ID NO: 8), PYY9-36 (SEQ ID NO: 9)
PYY(10-36) (SEQ ID NO: 10), PYY(11-36) (SEQ ID NO: 11), PYY(12-36) (SEQ ID NO:
12), PYY(13-36) (SEQ ID NO: 13), PYY(14-36) (SEQ ID NO: 14), PYY(15-36) (SEQ ID
NO: 15), PYY(16-36) (SEQ ID NO: 16), PYY(17-36) (SEQ ID NO: 17), PYY(18-36) (SEQ
ID NO: 18), PYY(19-36) (SEQ ID NO: 19), PYY(20-36) (SEQ ID NO: 20) and PYY(21-36)
(SEQ ID NO: 21). These peptides typically bind to the Y receptors in the brain and
elsewhere, especially the Y2 and/or Y5 receptors. Typically these peptides are synthesized in
endotoxin-free or pyrogen-free forms although this is not always necessary.
Other PYY peptides include those PYY peptides in which conservative amino acid
residue changes have beem made, for example, site specific mutation of a PYY peptide
including [Asp15] PYY(15-36) (SEQ ID NO: 90), [Thr13] PYY(13-36) (SEQ ID NO: 91),
[Val12] PYY(12-36)(SEQ ID NO: 92), [Glu11] PYY(11-36) (SEQ ID NO: 93), [Asp10]
PYY( 10-36) (SEQ ID NO: 94), [Val7] PYY(7-36) (SEQ ID NO: 95), [Asp6] PYY(6-36)
(SEQ ID NO: 96), [Gln4] PYY(4-36) (SEQ ID NO: 97), [Arg4] PYY(4-36) (SEQ ID NO: 98),
[Asn4] PYY(4-36) (SEQ ID NO: 99), [Val3] PYY(3-36) (SEQ ID NO: 100) and [Leu3]
PYY(3-36) (SEQ ID NO: 101). Other PYY peptides include those peptides in which at least
two conservative amino acid residue changes have been made including [Asp10, Asp15]
PYY(10-36) (SEQ ID NO: 102), [Asp6, Thr13] PYY(6-36) (SEQ ID NO: 103), [Asn4, Asp15]
PYY(4-36) (SEQ ID NO: 104) and [Leu3, Asp10] PYY(3-36) (SEQ ID NO: 105. Also
included are analogues of a PYY for example those disclosed in U.S. patents 5, 604,203 and
5,574,010; Balasubramaniam, et al., Peptide Research 1: 32 (1988); Japanese Patent
Application 2,225,497 (1990); Balasubramaniam, et al., Peptides 14: 1011, 1993; Grandt, et
at., Reg. Peptides 51: 151, (1994); PCT International Application 94/03380, U.S. patents 5,
604,203 and 5,574,010. These peptides typically bind to the Y receptors in the brain and
elsewhere, especially the Y2 and/or Y5 receptors. Typically these peptides are synthesized in
endotoxin-free or pyrogen-free forms although this is not always necessary.
PYY agonists include rat PYY (SEQ ID NO: 72) and the amino terminus truncated
forms corresponding to the human, pig PYY (SEQ ID NO: 73) and the amino terminus
truncated forms corresponding to the human and guinea pig PYY (SEQ ID NO: 74) and the
amino terminus truncated forms corresponding to the human.
According to the present invention a PYY peptide also includes the free bases, acid
addition salts or metal salts, such as potassium or sodium salts of the peptides, and PYY
peptides that have been modified by such processes as amidation, glycosylation, acylation,
sulfation, phosphorylation, acetylation, cyclization and other well known covalent
modification methods. These peptides typically bind to the Y receptors in the brain and
elsewhere, especially the Y2 and/or Y5 receptors. Typically these peptides are synthesized in
endotoxin-free or pyrogen-free forms although this is not always necessary.
NEUROPEPTIDE Y AGONISTS
NPY is another Y2 receptor-binding peptide. NPY peptides include full-length
NPY(l-36) (SEQ ID NO: 22) as well as well as fragments of NPY(l-36), which have been
truncated at the amino terminus. To be effective in binding the Y2 receptor, the NPY agonist
should have at least the last 11 amino acid residues at the carboxyl terminus, i.e., be
comprised of NPY(26-36) (SEQ ID NO: 23). Other examples of NPY agonists that bind to
the Y2 receptor are NPY(3-36) (SEQ ID NO: 24), NPY(4-36) (SEQ ID NO: 25), NPY(5-36)
(SEQ ID NO: 26), NPY(6-36) (SEQ ID NO: 27), NPY(7-36) (SEQ ID NO: 28), NPY(8-36)
(SEQ ID NO: 29), NPY(9-36) (SEQ ID NO: 30), NPY( 10-36) (SEQ ID NO: 31), NPY(11-
36) (SEQ ID NO: 32), NPY(12-36) (SEQ ID NO: 33), NPY(13-36) (SEQ ID NO: 34),
NPY(14-36) (SEQ ID NO: 35), NPY(15-36) (SEQ ID NO: 36), NPY(16-36) (SEQ ID NO:
37), NPY(17-36) (SEQ ID NO: 38), NPY(18-36) (SEQ ID NO: 39), NPY( 19-36) (SEQ ID
NO: 40), NPY(20-36) (SEQ ID NO: 41), NPY(21-36) (SEQ ID NO: 42), NPY(22-36) (SEQ
ID NO: 43), NPY(23-36) (SEQ ID NO: 44), NPY(24-36) (SEQ ID NO: 45) and NPY(25-36)
(SEQ ID NO: 46).
Other NPY agonists include rat NPY (SEQ ID NO: 75) and the amino terminus
truncated forms from NPY(3-36) to NPY(26-36) as in the human form, rabbit NPY (SEQ ID
NO: 76) and the amino terminus truncated forms from NPY(3-36) to NPY(26-36) as in the
human form, dog NPY (SEQ ID NO: 77) and the amino terminus truncated forms NPY(3-36)
to NPY(26-36) as in the human form, pig NPY (SEQ ID NO: 78) and the amino terminus
truncated forms from NPY(3-36) to NPY(26-36) as in the human form, cow NPY (SEQ ID
NO: 79) and the amino terminus truncated forms from NPY(3-36) to NPY26-36 as in the
human form, sheep NPY (SEQ ID NO:80) and the amino terminus truncated forms from
NPY(3-36) to NPY(26-36) as in the human form and guinea pig (SEQ 81) and the amino
terminus truncated forms from NPY(3-36) to NPY(26-36) as in the human form.
According to the present invention a NPY peptide also includes the free bases, acid
additoin salts or metal salts, such as potassium or sodium salts of the peptides, and NPY
peptides that have been modified by such processes as amidation, glycosylation, acylation,
sulfation, phosphorylation, acetylation, cyclization and other known covalent modification
methods. These peptides typically bind to the Y receptors in the brain and elsewhere,
especially the Y2 and/or Y5 receptors. Typically these peptides are synthesized in endotoxin-
free or pyrogen-free forms although this is not always necessary.
Pancreatic Peptide
Pancreatic Peptide (PP) and PP agonist also bind to the Y2 receptor. Examples of the
PP agonists are the full-length PP(l-36) (SEQ ID NO: 47) and a number of PP fragments,
which are truncated at the amino-terminus. To bind to the Y2 receptor the PP agonist must
have the last 11 amino acid residues at the carboxyl-terminus, PP(26-36), (SEQ ID NO: 48).
Examples of other PP, which bind to the Y2 receptor, are PP(3-36) (SEQ ID NO: 49), PP(4-
36) (SEQ ID NO: 50), PP(5-36) (SEQ ID NO: 51), PP(6-36) (SEQ ID NO: 52), PP(7-36)
(SEQ ID NO: 53), PP(8-36) (SEQ ID NO: 54), PP(9-36) (SEQ ID NO: 55), PP(10-36) (SEQ
ID NO: 56), PP(11-36) (SEQ ID NO: 57), PP(12-36) (SEQ ID NO: 58), PP(13-36) (SEQ ID
NO: 59), PP(14-36) (SEQ ID NO: 60), PP(15-36) (SEQ ID NO: 61), PP(16-36) (SEQ ID NO:
62), PP(17-36) (SEQ ID NO: 63), PP(18-36) (SEQ ID NO: 64), PP(19-36) (SEQ ID NO: 65),
PP(20-36) (SEQ ID NO: 66), PP(21-36) (SEQ ID NO: 67), PP(22-36) (SEQ ID NO: 68),
PP(23-36) (SEQ ID NO: 69), PP(24-36) (SEQ ID NO: 70) and PP(25-36) (SEQ ID NO: 71).
Other PP agonists include sheep PP (SEQ ID NO: 82) and the amino terminus
truncated forms from PP(3-36) to PP(26-36) as in the human form, pig PP (SEQ ID NO: 83)
and the amino terminus truncated forms from PP(3-36) to PP(26-36) as in the human form,
dog PP (SEQ ID NO: 84) and the amino terminus truncated forms PP(3-36) to PP(26-36) as
in the human form, cat PP (SEQ ID NO: 85) and the amino terminus truncated forms from
PP(3-36) to PP(26-36) as in the human form, cow PP (SEQ ID NO: 86) and the amino
terminus truncated forms from PP(3-36) to PP(26-36) as in the human form, rat PP (SEQ ID
NO:87) and the amino terminus truncated forms from PP(3-36) to PP(26-36) as in the human
form, mouse (SEQ 88) and the amino terminus truncated forms from PP(3-36) to PP(26-36)
as in the human form, and guinea pig PP (SEQ ID NO: 89).
According to the present invention a PP peptide also includes the free bases, acid
additoin salts or metal salts, such as potassium or sodium salts of the peptides, and PP
peptides that have been modified by such processes as amidation, glycosylation, acylation,
sulfation, phosphorylation, acetylation, cyclization, and other known covalent modification
methods. These peptides typically bind to the Y receptors in the brain and elsewhere,
especially the Y2 and/or Y5 receptors. Typically these peptides are synthesized in endotoxin-
free or pyrogen-free forms although this is not always necessary.
Mucosal Delivery Enhancing Agents
"Mucosal delivery enhancing agents" are defined as chemicals and other excipients
that, when added to a formulation comprising water, salts and/or common buffers and Y2
receptor-binding peptide (the control formulation) produce a formulation that produces a
significant increase in transport of Y2 receptor-binding peptide across a mucosa as measured
by the maximum blood, serum, or cerebral spinal fluid concentration (Cmax) or by the area
under the curve, AUC, in a plot of concentration versus time. A mucosa includes the nasal,
oral, intestional, buccal, bronchopulmonary, vaGlnal, and rectal mucosal surfaces and in fact
includes all mucus-secreting membranes lining all body cavities or passages that
communicate with the exterior. Mucosal delivery enhancing agents are sometimes called
carriers.
Endotoxin-free formulation
"Endotoxin-free formulation" means a formulation which contains a Y2-receptor-
binding peptide and one or more mucosal delivery enhancing agents that is substantially free
of endotoxins and/or related pyrogenic substances. Endotoxins include toxins that are
confined inside a microorganism and are released only when the microorganisms are broken
down or die. Pyrogenic substances include fever-inducing, thermostable substances
(glycoproteins) from the outer membrane of bacteria and other microorganisms. Both of these
substances can cause fever, hypotension and shock if administered to humans. Producing
formulations that are endotoxin-free can require special equipment, expert artisians, and can
be significantly more expensive than making formulations that are not endotoxin-free.
Because intravenous administration of NPY or PYY simultaneously with infusion of
endotoxin in rodents has been shown to prevent the hypotension and even death associated
with the administration of endotoxin alone (US Patent 4,839,343), producing endotoxin-free
formulations of these therapeutic agents would not be expected to be necessary for non-
parental (non-injected) administration.
Non-infused Administration
"Non-infused administration" means any method of delivery that does not involve an
injection directly into an artery or vein, a method which forces or drives (typically a fluid)
into something and especially to introduce into a body part by means of a needle, syringe or
other invasive method. Non-infused administration includes subcutaneous injection,
intramuscular injection, intraparitoneal injection and the non-injection methods of delivery to
a mucosa.
Treatment and Prevention of Obesity
As noted above, the instant invention provides improved and useful methods and
compositions for nasal mucosal delivery of a Y2 receptor-binding peptide to prevent and treat
obesity in mammalian subjects. As used herein, prevention and treatment of obesity mean
prevention of the onset or lowering the incidence or severity of clinical obesity by reducing
food intake during meals and/or reducing body weight during administration or maintaining a
reduced body weight following weight loss or before weight gain has occurred.
The instant invention provides improved and useful methods and compositions for
nasal mucosal deliverv of Y2 recentor-binding peptide to regions of the brain, for example,
the hypothalamus or the proopiomelanocortin (POMC) and NPY arcuate neurons, to prevent
and treat obesity in mammalian subjects. The Y2 receptor-binding peptide can also be
administered in conjunction with a Yl receptor antagonist such as dihyropyridine.
Methods and Compositions of Delivery
Improved methods and compositions for mucosal administration of Y2 receptor-
binding peptide to mammalian subjects optimize Y2 receptor-binding peptide dosing
schedules. The present invention provides mucosal delivery of Y2 receptor-binding peptide
formulated with one or more mucosal delivery-enhancing agents wherein Y2 receptor-
binding peptide dosage release is substantially normalized and/or sustained for an effective
delivery period of Y2 receptor-binding peptide release ranges from approximately 0.1 to 2.0
hours; 0.4 to 1.5 hours; 0.7 to 1.5 hours; or 0.8 to 1.0 hours; following mucosal
administration. The sustained release of Y2 receptor-binding peptide achieved may be
facilitated by repeated administration of exogenous Y2 receptor-binding peptide utilizing
methods and compositions of the present invention.
Compositions and Methods of Sustained Release
Improved compositions and methods for mucosal administration of Y2 receptor-
binding peptide to mammalian subjects optimize Y2 receptor-binding peptide dosing
schedules. The present invention provides improved mucosal (e.g., nasal) delivery of a
formulation comprising Y2 receptor-binding peptide in combination with one or more
mucosal delivery-enhancing agents and an optional sustained release-enhancing agent or
agents. Mucosal delivery-enhancing agents of the present invention yield an effective
increase in delivery, e.g., an increase in the maximal plasma concentration (CmaX) to enhance
the therapeutic activity of mucosally-administered Y2 receptor-binding peptide. A second
factor affecting therapeutic activity of Y2 receptor-binding peptide in the blood plasma and
CNS is residence time (RT). Sustained release-enhancing agents, in combination with
intranasal delivery-enhancing agents, increase Cmax and increase residence time (RT) of Y2
receptor-binding peptide. Polymeric delivery vehicles and other agents and methods of the
present invention that yield sustained release-enhancing formulations, for example,
polyethylene glycol (PEG), are disclosed herein. The present invention provides an improved
Y2 receptor-binding peptide delivery method and dosage form for treatment of symptoms
related to obesity, colon cancer, pancreatic cancer, or breast cancer in mammalian subjects.
Within the mucosal delivery formulations and methods of the invention, the Y2
receptor-binding peptide is frequently combined or coordinately administered with a suitable
carrier or vehicle for mucosal delivery. As used herein, the term "carrier" means a
pharmaceutically acceptable solid or liquid filler, diluent or encapsulating material. A water-
containing liquid carrier can contain pharmaceutically acceptable additives such as acidifying
agents, alkalizing agents, antimicrobial preservatives, antioxidants, buffering agents,
chelating agents, complexing agents, solubilizing agents, humectants, solvents, suspending
and/or viscosity-increasing agents, tonicity agents, wetting agents or other biocompatible
materials. A tabulation of ingredients listed by the above categories, can be found in the U.S.
Pharmacopeia National Formulary, 1857-1859, (1990). Some examples of the materials
which can serve as pharmaceutically acceptable carriers are sugars, such as lactose, glucose
and sucrose; starches such as corn starch and potato starch; cellulose and its derivatives such
as sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; powdered
tragacanth; malt; gelatin; talc; excipients such as cocoa butter and suppository waxes; oils
such as peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil and soybean
oil; glycols, such as propylene glycol; polyols such as glycerin, sorbitol, mannitol and
polyethylene glycol; esters such as ethyl oleate and ethyl laurate; agar; buffering agents such
as magnesium hydroxide and aluminum hydroxide; alGlnic acid; pyrogen free water; isotonic
saline;" Ringer's solution, ethyl alcohol and phosphate buffer solutions, as well as other non
toxic compatible substances used in pharmaceutical formulations. Wetting agents,
emulsifiers and lubricants such as sodium lauryl sulfate and magnesium stearate, as well as
coloring agents, release agents, coating agents, sweetening, flavoring and perfuming agents,
preservatives and antioxidants can also be present in the compositions, according to the
desires of the formulator. Examples of pharmaceutically acceptable antioxidants include,
water soluble antioxidants such as ascorbic acid, cysteine hydrochloride, sodium bisulfite,
sodium metabisulfite, sodium sulfite and the like; oil-soluble antioxidants such as ascorbyl
palmitate, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), lecithin,
propyl gallate, alpha-tocopherol and the like; and metal-chelating agents such as citric acid,
ethylenediamine tetraacetic acid (EDTA), sorbitol, tartaric acid, phosphoric acid and the like.
The amount of active ingredient that can be combined with the carrier materials to produce a
single dosage form will vary depending upon the particular mode of administration.
Within the mucosal delivery compositions and methods of the invention, various
delivery-enhancing agents are employed which enhance delivery of Y2 receptor-binding
peptide into or across a mucosal surface. In this regard, delivery of Y2 receptor-binding
peptide across the mucosal epithelium can occur "transcellularly" or "paracellularly". The
extent to which these pathways contribute to the overall flux and bioavailability of the Y2
receptor-binding peptide depends upon the environment of the mucosa, the physico-chemical
properties the active agent, and on the properties of the mucosal epithelium. Paracellular
transport involves only passive diffusion, whereas transcellular transport can occur by
passive, facilitated or active processes. Generally, hydrophilic, passively transported, polar
solutes diffuse through the paracellular route, while more lipophilic solutes use the
transcellular route. Absorption and bioavailability (e.g., as reflected by a permeability
coefficient or physiological assay), for diverse, passively and actively absorbed solutes, can
be readily evaluated, in terms of both paracellular and transcellular delivery components, for
any selected Y2 receptor-binding peptide within the invention. For passively absorbed drugs,
the relative contribution of paracellular and transcellular pathways to drug transport depends
upon the pKa, partition coefficient, molecular radius and charge of the drug, the pH of the
luminal environment in which the drug is delivered, and the area of the absorbing surface.
The paracellular route represents a relatively small fraction of accessible surface area of the
nasal mucosal epithelium. In general terms, it has been reported that cell membranes occupy
a mucosal surface area that is a thousand times greater than the area occupied by the
paracellular spaces. Thus, the smaller accessible area, and the size- and charge-based
discrimination against macromolecular permeation would suggest that the paracellular route
would be a generally less favorable route than transcellular delivery for drug transport.
Surprisingly, the methods and compositions of the invention provide for significantly
enhanced transport of biotherapeutics into and across mucosal epithelia via the paracellular
route. Therefore, the methods and compositions of the invention successfully target both
paracellular and transcellular routes, alternatively or within a single method or composition.
As used herein, "mucosal delivery-enhancing agents" include agents which enhance
the release or solubility (e.g., from a formulation delivery vehicle), diffusion rate, penetration
capacity and timing, uptake, residence time, stability, effective half-life, peak or sustained
concentration levels, clearance and other desired mucosal delivery characteristics (e.g., as
measured at the site of delivery, or at a selected target site of activity such as the bloodstream
or central nervous system) of Y2 receptor-binding peptide or other biologically active
compound(s). Enhancement of mucosal delivery can thus occur by any of a variety of
mechanisms, for example by increasing the diffusion, transport, persistence or stability of Y2
receptor-binding peptide, increasing membrane fluidity, modulating the availability or action
of calcium and other ions that regulate intracellular or paracellular permeation, solubilizing
mucosal membrane components (e.g., lipids), chanGlng non-protein and protein sulfhydryl
levels in mucosal tissues, increasing water flux across the mucosal surface, modulating
epithelial junctional physiology, reducing the viscosity of mucus overlying the mucosal
epithelium, reducing mucociliary clearance rates, and other mechanisms.
As used herein, a "mucosally effective amount of Y2 receptor-binding peptide"
contemplates effective mucosal delivery of Y2 receptor-binding peptide to a target site for
drug activity in the subject that may involve a variety of delivery or transfer routes. For
example, a given active agent may find its way through clearances between cells of the
mucosa and reach an adjacent vascular wall, while by another route the agent may, either
passively or actively, be taken up into mucosal cells to act within the cells or be discharged or
transported out of the cells to reach a secondary target site, such as the systemic circulation.
The methods and compositions of the invention may promote the translocation of active
agents along one or more such alternate routes, or may act directly on the mucosal tissue or
proximal vascular tissue to promote absorption or penetration of the active agent(s). The
promotion of absorption or penetration in this context is not limited to these mechanisms.
As used herein "peak concentration (Cmax) of Y2 receptor-binding peptide in a blood
plasma", "area under concentration vs. time curve (AUC) of Y2 receptor-binding peptide in a
blood plasma", "time to maximal plasma concentration (tmax) of Y2 receptor-binding peptide
in a blood plasma" are pharmacokinetic parameters known to one skilled in the art. Laursen
et al., Eur. J. Endocrinology, 135: 309-315, 1996. The "concentration vs. time curve"
measures the concentration of Y2 receptor-binding peptide in a blood serum of a subject vs.
time after administration of a dosage of Y2 receptor-binding peptide to the subject either by
intranasal, intramuscular, subcutaneous, or other parenteral route of administration. "Cmax" is
the maximum concentration of Y2 receptor-binding peptide in the blood serum of a subject
following a single dosage of Y2 receptor-binding peptide to the subject. "tmax" is the time to
reach maximum concentration of Y2 receptor-binding peptide in a blood serum of a subject
following administration of a single dosage of Y2 receptor-binding peptide to the subject.
As used herein, "area under concentration vs. time curve (AUC) of Y2 receptor-
binding peptide in a blood plasma" is calculated according to the linear trapezoidal rule and
with addition of the residual areas. A decrease of 23% or an increase of 30% between two
dosages would be detected with a probability of 90% (type II error (5 = 10%). The "delivery
rate" or "rate of absorption" is estimated by comparison of the time (tmax) to reach the
maximum concentration (Cmax). Both Cmax and tmax are analyzed using non-parametric
methods. Comparisons of the pharmacokinetics of intramuscular, subcutaneous, intravenous
and intranasal Y2 receptor-binding peptide administrations were performed by analysis of
variance (ANOVA). For pair wise comparisons a Bonferroni-Holmes sequential procedure
was used to evaluate significance. The dose-response relationship between the three nasal
doses was estimated by regression analysis. P given as mean values +/- SEM.
While the mechanism of absorption promotion may vary with different mucosal
delivery-enhancing agents of the invention, useful reagents in this context will not
substantially adversely affect the mucosal tissue and will be selected according to the
physicochemical characteristics of the particular Y2 receptor-binding peptide or other active
or delivery-enhancing agent. In this context, delivery-enhancing agents that increase
penetration or permeability of mucosal tissues will often result in some alteration of the
protective permeability barrier of the mucosa. For such delivery-enhancing agents to be of
value within the invention, it is generally desired that any significant changes in permeability
of the mucosa be reversible within a time frame appropriate to the desired duration of drug
delivery. Furthermore, there should be no substantial, cumulative toxicity, nor any
permanent deleterious changes induced in the barrier properties of the mucosa with long-term
use.
Within certain aspects of the invention, absorption-promoting agents for coordinate
administration or combinatorial formulation with Y2 receptor-binding peptide of the
invention are selected from small hydrophilic molecules, including but not limited to,
dimethyl sulfoxide (DMSO), dimethylformamide, ethanol, propylene glycol, and the 2-
pyrrolidones. Alternatively, long-chain amphipathic molecules, for example, deacylmethyl
sulfoxide, azone, sodium laurylsulfate, oleic acid, and the bile salts, may be employed
toenhance mucosal penetration of the Y2 receptor-binding peptide. In additional aspects,
surfactants (e.g., polysorbates) are employed as adjunct compounds, processing agents, or
formulation additives to enhance intranasal delivery of the Y2 receptor-binding peptide.
Agents such as DMSO, polyethylene glycol, and ethanol can, if present in sufficiently high
concentrations in delivery environment (e.g., by pre-administration or incorporation in a
therapeutic formulation), enter the aqueous phase of the mucosa and alter its solubilizing
properties, thereby enhancing the partitioning of the Y2 receptor-binding peptide from the
vehicle into the mucosa.
Additional mucosal delivery-enhancing agents that are useful within the coordinate
administration and processing methods and combinatorial formulations of the invention
include, but are not limited to, mixed micelles; enamines; nitric oxide donors (e.g., S-nitroso-
N-acetyl-DL-penicillamine, NOR1, N0R4~which are preferably co-administered with an
NO scavenger such as carboxy-PITO or doclofenac sodium); sodium salicylate; glycerol
esters of acetoacetic acid (e.g., glyceryl-l,3-diacetoacetate or l,2-isopropylideneglycerine-3-
acetoacetate); and other release-diffusion or intra- or trans-epithelial penetration-promoting
agents that are physiologically compatible for mucosal delivery. Other absorption-promoting
agents are selected from a variety of carriers, bases and excipients that enhance mucosal
delivery, stability, activity or trans-epithelial penetration of the Y2 receptor-binding peptide.
These include, inter alia, cyclodextrins and p-cyclodextrin derivatives (e.g., 2-
hydroxypropyl-b-cyclodextrin and heptakis(2,6-di-O-methyl-ß-cyclodextrin). These
compounds, optionally conjugated with one or more of the active ingredients and further
optionally formulated in an oleaGlnous base, enhance bioavailability in the mucosal
formulations of the invention. Yet additional absorption-enhancing agents adapted for
mucosal delivery include medium-chain fatty acids, including mono- and diglycerides (e.g.,
sodium caprate--extracts of coconut oil, Capmul), and triglycerides (e.g., amylodextrin,
Estaram 299, Miglyol 810).
The mucosal therapeutic and prophylactic compositions of the present invention may
be supplemented with any suitable penetration-promoting agent that facilitates absorption,
diffusion, or penetration of Y2 receptor-binding peptide across mucosal barriers. The
penetration promoter may be any promoter that is pharmaceutically acceptable. Thus, in
more detailed aspects of the invention compositions are provided that incorporate one or
more penetration-promoting agents selected from sodium salicylate and salicylic acid
derivatives (acetyl salicylate, choline salicylate, salicylamide, etc.); amino acids and salts
thereof (e.g. monoaminocarboxlic acids such as glycine, alanine, phenylalanine, proline,
hydroxyproline, etc.; hydroxyamino acids such as serine; acidic amino acids such as aspartic
acid, glutamic acid, etc; and basic amino acids such as lysine etc—inclusive of their alkali
metal or alkaline earth metal salts); and N-acetylamino acids (N-acetylalanine, N-
acetylphenylalanine, N-acetylserine, N-acetylglycine, N-acetyllysine, N-acetylglutamic acid,
N-acetylproline, N-acetylhydroxyproline, etc.) and their salts (alkali metal salts and alkaline
earth metal salts). Also provided as penetration-promoting agents within the methods and
compositions of the invention are substances which are generally used as emulsifiers (e.g.
sodium oleyl phosphate, sodium lauryl phosphate, sodium lauryl sulfate, sodium myristyl
sulfate, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, etc.), caproic acid, lactic
acid, malic acid and citric acid and alkali metal salts thereof, pyrrolidonecarboxylic acids,
alkylpyrrolidonecarboxylic acid esters, N-alkylpyrrolidones, proline acyl esters, and the like.
Within various aspects of the invention, improved nasal mucosal delivery
formulations and methods are provided that allow delivery of Y2 receptor-binding peptide
and other therapeutic agents within the invention across mucosal barriers between
administration and selected target sites. Certain formulations are specifically adapted for a
selected target cell, tissue or organ, or even a particular disease state. In other aspects,
formulations and methods provide for efficient, selective endo- or transcytosis of Y2
receptor-binding peptide specifically routed along a defined intracellular or intercellular
pathway. Typically, the Y2 receptor-binding peptide is efficiently loaded at effective
concentration levels in a carrier or other delivery vehicle, and is delivered and maintained in a
stabilized form, e.g., at the nasal mucosa and/or during passage through intracellular
compartments and membranes to a remote target site for drug action (e.g., the blood stream or
a defined tissue, organ, or extracellular compartment). The Y2 receptor-binding peptide may
be provided in a delivery vehicle or otherwise modified (e.g., in the form of a prodrug),
wherein release or activation of the Y2 receptor-binding peptide is triggered by a
physiological stimulus (e.g. pH change, lysosomal enzymes, etc.) Often, the Y2 receptor-
binding peptide is pharmacologically inactive until it reaches its target site for activity. In
most cases, the Y2 receptor-binding peptide and other formulation components are non-toxic
and non-immunogenic. In this context, carriers and other formulation components are
generally selected for their ability to be rapidly degraded and excreted under physiological
conditions. At the same time, formulations are chemically and physically stable in dosage
form for effective storage.
Peptide and Protein Analogs and Mimetics
Included within the definition of biologically active peptides and proteins for use
within the invention are natural or synthetic, therapeutically or prophylactically active,
peptides (comprised of two or more covalently linked amino acids), proteins, peptide or
protein fragments, peptide or protein analogs, and chemically modified derivatives or salts of
active peptides or proteins. A wide variety of useful analogs and mimetics of Y2 receptor-
binding peptide are contemplated for use within the invention and can be produced and tested
for biological activity according to known methods. Often, the peptides or proteins of Y2
receptor-binding peptide or other biologically active peptides or proteins for use within the
invention are muteins that are readily obtainable by partial substitution, addition, or deletion
of amino acids within a naturally occurring or native (e.g., wild-type, naturally occurring
mutant, or allelic variant) peptide or protein sequence. Additionally, biologically active
fragments of native peptides or proteins are included. Such mutant derivatives and fragments
substantially retain the desired biological activity of the native peptide or proteins. In the
case of peptides or proteins having carbohydrate chains, biologically active variants marked
by alterations in these carbohydrate species are also included within the invention.
As used herein, the term "conservative amino acid substitution" refers to the general
interchangeability of amino acid residues having similar side chains. For example, a
commonly interchangeable group of amino acids having aliphatic side chains is alanine,
valine, leucine, and isoleucine; a group of amino acids having aliphatic-hydroxyl side chains
is serine and threomine; a group of amino acids having amide-containing side chains is
asparaGlne and glutamine; a group of amino acids having aromatic side chains is
phenylalanine, tyrosine, and tryptophan; a group of amino acids having basic side chains is
lysine, arGlnine, and histidine; and a group of amino acids having sulfur-containing side
chains is cysteine and methionine. Examples of conservative substitutions include the
substitution of a non-polar (hydrophobic) residue such as isoleucine, valine, leucine or
methionine for another. Likewise, the present invention contemplates the substitution of a
polar (hydrophilic) residue such as between arGlnine and lysine, between glutamine and
asparaGlne, and between threonine and serine. Additionally, the substitution of a basic
residue such as lysine, arGlnine or histidine for another or the substitution of an acidic residue
such as aspartic acid or glutamic acid for another is also contemplated. Exemplary
conservative amino acids substitution groups are: valine-leucine-isoleucine, phenylalanine-
tyrosine, lysine-arGlnine, alanine-valine, and asparaGlne-glutamine. By aligning a peptide or
protein analog optimally with a corresponding native peptide or protein, and by using
appropriate assays, e.g., adhesion protein or receptor binding assays, to determine a selected
biological activity, one can readily identify operable peptide and protein analogs for use
within the methods and compositions of the invention. Operable peptide and protein analogs
are typically specifically immunoreactive with antibodies raised to the corresponding native
peptide or protein.
An approach for stabilizing solid protein formulations of the invention is to increase
the physical stability of purified, e.g., lyophilized, protein. This will inhibit aggregation via
hydrophobic interactions as well as via covalent pathways that may increase as proteins
unfold. Stabilizing formulations in this context often include polymer-based formulations,
for example a biodegradable hydrogel formulation/delivery system. As noted above, the
critical role of water in protein structure, function, and stability is well known. Typically,
proteins are relatively stable in the solid state with bulk water removed. However, solid
therapeutic protein formulations may become hydrated upon storage at elevated humidities or
during delivery from a sustained release composition or device. The stability of proteins
generally drops with increasing hydration. Water can also play a significant role in solid
protein aggregation, for example, by increasing protein flexibility resulting in enhanced
accessibility of reactive groups, by providing a mobile phase for reactants, and by serving as
a reactant in several deleterious processes such as beta-elimination and hydrolysis.
Protein preparations containing between about 6% to 28% water are the most
unstable. Below this level, the mobility of bound water and protein internal motions are low.
Above this level, water mobility and protein motions approach those of full hydration. Up to
a point, increased susceptibility toward solid-phase aggregation with increasing hydration has
been observed in several systems. However, at higher water content, less aggregation is
observed because of the dilution effect.
In accordance with these principles, an effective method for stabilizing peptides and
proteins against solid-state aggregation for mucosal delivery is to control the water content in
a solid formulation and maintain the water activity in the formulation at optimal levels. This
level depends on the nature of the protein, but in general, proteins maintained below their
"monolayer" water coverage will exhibit superior solid-state stability.
A variety of additives, diluents, bases and delivery vehicles are provided within the
invention that effectively control water content to enhance protein stability. These reagents
and carrier materials effective as anti-aggregation agents in this sense include, for example,
polymers of various functionalities, such as polyethylene glycol, dextran, diethylaminoethyl
dextran, and carboxymethyl cellulose, which significantly increase the stability and reduce
the solid-phase aggregation of peptides and proteins admixed therewith or linked thereto. In
some instances, the activity or physical stability of proteins can also be enhanced by various
additives to aqueous solutions of the peptide or protein drugs. For example, additives, such
as polyols (including sugars), amino acids, proteins such as collagen and gelatin, and various
salts may be used.
Certain additives, in particular sugars and other polyols, also impart significant
physical stability to dry, e.g., lyophilized proteins. These additives can also be used within
the invention to protect the proteins against aggregation not only during lyophilization but
also during storage in the dry state. For example sucrose and Ficoll 70 (a polymer with
sucrose units) exhibit significant protection against peptide or protein aggregation during
solid-phase incubation under various conditions. These additives may also enhance the
stability of solid proteins embedded within polymer matrices.
Yet additional additives, for example sucrose, stabilize proteins against solid-state
aggregation in humid atmospheres at elevated temperatures, as may occur in certain
sustained-release formulations of the invention. Proteins such as gelatin and collagen also
serve as stabilizing or bulking agents to reduce denaturation and aggregation of unstable
proteins in this context. These additives can be incorporated into polymeric melt processes
and compositions within the invention. For example, polypeptide microparticles can be
prepared by simply lyophilizing or spray drying a solution containing various stabilizing
additives described above. Sustained release of unaggregated peptides and proteins can
thereby be obtained over an extended period of time.
Various additional preparative components and methods, as well as specific
formulation additives, are provided herein which yield formulations for mucosal delivery of
aggregation-prone peptides and proteins, wherein the peptide or protein is stabilized in a
substantially pure, unaggregated form using a solubilization agent. A range of components
and additives are contemplated for use within these methods and formulations. Exemplary of
these solubilization agents are linked dimers of cyclodextrins (CDs), which selectively bind
hydrophobic side chains of polypeptides. These CD dimers have been found to bind to
hydrophobic patches of proteins in a manner that significantly inhibits aggregation. . This
inhibition is selective with respect to both the CD dimer and the protein involved. Such
selective inhibition of protein aggregation provides additional advantages within the
intranasal delivery methods and compositions of the invention. Additional agents for use in
this context include CD timers and tetramers with varying geometries controlled by the
linkers that specifically block aggregation of peptides and protein. Yet solubilization agents
and methods for incorporation within the invention involve the use of peptides and peptide
mimetics to selectively block protein-protein interactions. In one aspect, the specific binding
of hydrophobic side chains reported for CD multimers is extended to proteins via the use of
peptides and peptide mimetics that similarly block protein aggregation. A wide range of
suitable methods and anti-aggregation agents are available for incorporation within the
compositions and procedures of the invention.
Charge Modifying and pH Control Agents and Methods
To improve the transport characteristics of biologically active agents (including Y2
receptor-binding peptide, other active peptides and proteins, and macromolecular and small
molecule drugs) for enhanced delivery across hydrophobic mucosal membrane barriers, the
invention also provides techniques and reagents for charge modification of selected
biologically active agents or delivery-enhancing agents described herein. In this regard, the
relative permeabilities of macromolecules is generally be related to their partition
coefficients. The degree of ionization of molecules, which is dependent on the pKa of the
molecule and the pH at the mucosal membrane surface, also affects permeability of the
molecules. Permeation and partitioning of biologically active agents, including Y2 receptor-
binding peptide and analogs of the invention, for mucosal delivery may be facilitated by
charge alteration or charge spreading of the active agent or permeabilizing agent, which is
achieved, for example, by alteration of charged functional groups, by modifying the pH of the
delivery vehicle or solution in which the active agent is delivered, or by coordinate
administration of a charge- or pH-altering reagent with the active agent.
Consistent with these general teachings, mucosal delivery of charged macromolecular
species, including Y2 receptor-binding peptide and other biologically active peptides and
proteins, within the methods and compositions of the invention is substantially improved
when the active agent is delivered to the mucosal surface in a substantially un-ionized, or
neutral, electrical charge state.
Certain Y2 receptor-binding peptide and other biologically active peptide and protein
components of mucosal formulations for use within the invention will be charge modified to
yield an increase in the positive charge density of the peptide or protein. These modifications
extend also to cationization of peptide and protein conjugates, carriers and other delivery
forms disclosed herein. Cationization offers a convenient means of altering the
biodistribution and transport properties of proteins and macromolecules within the invention.
Cationization is undertaken in a manner that substantially preserves the biological activity of
the active agent and limits potentially adverse side effects, including tissue damage and
toxicity.
Degradative Enzyme Inhibitory Agents and Methods
Another excipient that may be included in a trans-mucosal preparation is a
degradative enzyme inhibitor. Exemplary mucoadhesive polymer-enzyme inhibitor
complexes that are useful within the mucosal delivery formulations and methods of the
invention include, but are not limited to: Carboxymethylcellulose-pepstatin (with anti-pepsin
activity); Poly(acrylic acid)-Bowman-Birk inhibitor (anti-chymotrypsin); Poly(acrylic acid)-
chymostatin (anti-chymotrypsin); Poly(acrylic acid)-elastatinal (anti-elastase);
Carboxymethylcellulose-elastatinal (anti-elastase); Polycarbophil—elastatinal (anti-elastase);
Chitosan—antipain (anti-trypsin); Poly(acrylic acid)—bacitracin (anti-aminopeptidase N);
Chitosan—EDTA (anti-aminopeptidase N, anti-carboxypeptidase A); Chitosan—EDTA—
antipain (anti-trypsin, anti-chymotrypsin, anti-elastase). As described in further detail below,
certain embodiments of the invention will optionally incorporate a novel chitosan derivative
or chemically modified form of chitosan. One such novel derivative for use within the
invention is denoted as a P-[l?4]-2-guanidino-2-deoxy-D-glucose polymer (poly-GuD).
Any inhibitor that inhibits the activity of an enzyme to protect the biologically active
agent(s) may be usefully employed in the compositions and methods of the invention. Useful
enzyme inhibitors for the protection of biologically active proteins and peptides include, for
example, soybean trypsin inhibitor, pancreatic trypsin inhibitor, chymotrypsin inhibitor and
trypsin and chrymotrypsin inhibitor isolated from potato (solanum tuberosum L.) tubers. A
combination or mixtures of inhibitors may be employed. Additional inhibitors of proteolytic
enzymes for use within the invention include ovomucoid-enzyme, gabaxate mesylate, alpha1-
antitrypsin, aprotinin, amastatin, bestatin, puromycin, bacitracin, leupepsin, alpha2-
macroglobulin, pepstatin and egg white or soybean trypsin inhibitor. These and other
inhibitors can be used alone or in combination. The inhibitor(s) may be incorporated in or
bound to a carrier, e.g., a hydrophilic polymer, coated on the surface of the dosage form
which is to contact the nasal mucosa, or incorporated in the superficial phase of the surface,
in combination with the biologically active agent or in a separately administered (e.g., pre-
administered) formulation.
The amount of the inhibitor, e.g., of a proteolytic enzyme inhibitor that is optionally
incorporated in the compositions of the invention will vary depending on (a) the properties of
the specific inhibitor, (b) the number of functional groups present in the molecule (which
may be reacted to introduce ethylenic unsaturation necessary for copolymerization with
hydrogel forming monomers), and (c) the number of lectin groups, such as glycosides, which
are present in the inhibitor molecule. It may also depend on the specific therapeutic agent
that is intended to be administered. Generally speaking, a useful amount of an enzyme
inhibitor is from about 0.1 mg/ml to about 50 mg/ml, often from about 0.2 mg/ml to about 25
mg/ml, and more commonly from about 0.5 mg/ml to 5 mg/ml of the of the formulation (i.e.,
a separate protease inhibitor formulation or combined formulation with the inhibitor and
biologically active agent).
In the case of trypsin inhibition, suitable inhibitors may be selected from, e.g.,
aprotinin, BBI, soybean trypsin inhibitor, chicken ovomucoid, chicken ovoinhibitor, human
pancreatic trypsin inhibitor, camostat mesilate, flavonoid inhibitors, antipain, leupeptin , p-
aminobenzamidine, AEBSF, TLCK (tosyllysine chloromethylketone), APMSF, DFP, PMSF,
and poly(acrylate) derivatives. In the case of chymotrypsin inhibition, suitable inhibitors may
be selected from, e.g., aprotinin, BBI, soybean trypsin inhibitor, chymostatin,
benzyloxycarbonyl-Pro-Phe-CHO, FK-448, chicken ovoinhibitor, sugar biphenylboronic
acids complexes, DFP, PMSF, P-phenylpropionate, and poly(acrylate) derivatives. In the
case of elastase inhibition, suitable inhibitors may be selected from, e.g., elastatinal,
methoxysuccinyl-Ala-Ala-Pro-Val-chloromethylketone (MPCMK), BBI, soybean trypsin
inhibitor, chicken ovoinhibitor, DFP, and PMSF.
Additional enzyme inhibitors for use within the invention are selected from a wide
range of non-protein inhibitors that vary in their degree of potency and toxicity. As described
in further detail below, immobilization of these adjunct agents to matrices or other delivery
vehicles, or development of chemically modified analogues, may be readily implemented to
reduce or even eliminate toxic effects, when they are encountered. Among this broad group
of candidate enzyme inhibitors for use within the invention are organophosphorous inhibitors,
such as diisopropylfluorophosphate (DFP) and phenylmethylsulfonyl fluoride (PMSF), which
are potent, irreversible inhibitors of serine proteases (e.g., trypsin and chymotrypsin). The
additional inhibition of acetylcholinesterase by these compounds makes them highly toxic in
uncontrolled delivery settings. Another candidate inhibitor, 4-(2-Aminoethyl)-
benzenesulfonyl fluoride (AEBSF), has an inhibitory activity comparable to DFP and PMSF,
but it is markedly less toxic. (4-Aminophenyl)-methanesulfonyl fluoride hydrochloride
(APMSF) is another potent inhibitor of trypsin, but is toxic in uncontrolled settings, In
contrast to these inhibitors, 4-(4-isopropylpiperadinocarbonyl)phenyl 1, 2,3,4,-tetrahydro-l-
naphthoate methanesulphonate (FK-448) is a low toxic substance, representing a potent and
specific inhibitor of chymotrypsin. Further representatives of this non-protein group of
inhibitor candidates, and also exhibiting low toxic risk, are camostat mesilate (N,N'-dimethyl
carbamoylmethyl-ß-(p '-guanidino-benzoyloxy)phenylacetate methane-sulphonate).
Yet another type of enzyme inhibitory agent for use within the methods and
compositions of the invention are amino acids and modified amino acids that interfere with
enzymatic degradation of specific therapeutic compounds. For use in this context, amino
acids and modified amino acids are substantially non-toxic and can be produced at a low cost.
However, due to their low molecular size and good solubility, they are readily diluted and
absorbed in mucosal environments. Nevertheless, under proper conditions, amino acids can
act as reversible, competitive inhibitors of protease enzymes. Certain modified amino acids
can display a much stronger inhibitory activity. A desired modified amino acid in this
context is known as a 'transition-state' inhibitor. The strong inhibitory activity of these
compounds is based on their structural similarity to a substrate in its transition-state
geometry, while they are generally selected to have a much higher affinity for the active site
of an enzyme than the substrate itself. Transition-state inhibitors are reversible, competitive
inhibitors. Examples of this type of inhibitor are a-aminoboronic acid derivatives, such as
boro-leucine, boro-valine and boro-alanine. The boron atom in these derivatives can form a
tetrahedral boronate ion that is believed to resemble the transition state of peptides during
their hydrolysis by aminopeptidases. These amino acid derivatives are potent and reversible
inhibitors of aminopeptidases and it is reported that boro-leucine is more than 100-times
more effective in enzyme inhibition than bestatin and more than 1000-times more effective
than puromycin. Another modified amino acid for which a strong protease inhibitory activity
has been reported is N-acetylcysteine, which inhibits enzymatic activity of aminopeptidase N.
This adjunct agent also displays mucolytic properties that can be employed within the
methods and compositions of the invention to reduce the effects of the mucus diffusion
barrier.
Still other useful enzyme inhibitors for use within the coordinate administration
methods and combinatorial formulations of the invention may be selected from peptides and
modified peptide enzyme inhibitors. An important representative of this class of inhibitors is
the cyclic dodecapeptide, bacitracin, obtained from Bacillus licheniformis. In addition to
these types of peptides, certain dipeptides and tripeptides display weak, non-specific
inhibitory activity towards some protease. By analogy with amino acids, their inhibitory
activity can be improved by chemical modifications. For example, phosphinic acid dipeptide
analogues are also 'transition-state' inhibitors with a strong inhibitory activity towards
aminopeptidases. They have reportedly been used to stabilize nasally administered leucine
enkephalin. Another example of a transition-state analogue is the modified pentapeptide
pepstatin, which is a very potent inhibitor of pepsin. Structural analysis of pepstatin, by
testing the inhibitory activity of several synthetic analogues, demonstrated the major
structure-function characteristics of the molecule responsible for the inhibitory activity.
Another special type of modified peptide includes inhibitors with a terminally located
aldehyde function in their structure. For example, the sequence benzyloxycarbonyl-Pro-Phe-
CHO, which fulfills the known primary and secondary specificity requirements of
chymotrypsin, has been found to be a potent reversible inhibitor of this target proteinase. The
chemical structures of further inhibitors with a terminally located aldehyde function, e.g.
antipain, leupeptin, chymostatin and elastatinal, are also known in the art, as are the structures
of other known, reversible, modified peptide inhibitors, such as phosphoramidon, bestatin,
puromycin and amastatin.
Due to their comparably high molecular mass, polypeptide protease inhibitors are
more amenable than smaller compounds to concentrated delivery in a drug-carrier matrix.
Additional agents for protease inhibition within the formulations and methods of the
invention involve the use of complexing agents. These agents mediate enzyme inhibition by
depriving the intranasal environment (or preparative or therapeutic composition) of divalent
cations which are co-factors for many proteases. For instance, the complexing agents EDTA
and DTPA as coordinately administered or combinatorially formulated adjunct agents, in
suitable concentration, will be sufficient to inhibit selected proteases to thereby enhance
intranasal delivery of biologically active agents according to the invention. Further
representatives of this class of inhibitory agents are EGTA, 1,10-phenanthroline and
hydroxychinoline. In addition, due to their propensity to chelate divalent cations, these and
other complexing agents are useful within the invention as direct, absorption-promoting
agents.
As noted in more detail elsewhere herein, it is also contemplated to use various
polymers, particularly mucoadhesive polymers, as enzyme inhibiting agents within the
coordinate administration, multi-processing and/or combinatorial formulation methods and
compositions of the invention. For example, poly(acrylate) derivatives, such as poly(acrylic
acid) and polycarbophil, can affect the activity of various proteases, including trypsin,
chymotrypsin. The inhibitory effect of these polymers may also be based on the
complexation of divalent cations such as Ca2+ and Zn2+. It is further contemplated that these
polymers may serve as conjugate partners or carriers for additional enzyme inhibitory agents,
as described above. For example, a chitosan-EDTA conjugate has been developed and is
useful within the invention that exhibits a strong inhibitory effect towards the enzymatic
activity of zinc-dependent proteases. The mucoadhesive properties of polymers following
covalent attachment of other enzyme inhibitors in this context are not expected to be
substantially compromised, nor is the general utility of such polymers as a delivery vehicle
for biologically active agents within the invention expected to be diminished. On the
contrary, the reduced distance between the delivery vehicle and mucosal surface afforded by
the mucoadhesive mechanism will minimize presystemic metabolism of the active agent,
while the covalently bound enzyme inhibitors remain concentrated at the site of drug
delivery, minimizing undesired dilution effects of inhibitors as well as toxic and other side
effects caused thereby. In this manner, the effective amount of a coordinately administered
enzyme inhibitor can be reduced due to the exclusion of dilution effects.
Exemplary mucoadhesive polymer-enzyme inhibitor complexes that are useful within
the mucosal formulations and methods of the invention include, but are not limited to:
Carboxymethylcellulose-pepstatin (with anti-pepsin activity); Poly(acrylic acid)-Bowman-
Birk inhibitor (anti-chymotrypsin); Poly(acrylic acid)-chymostatin (anti-chymotrypsin);
Poly(acrylic acid)-elastatinal (anti-elastase); Carboxymethylcellulose-elastatinal (anti-
elastase); Polycarbophil—elastatinal (anti-elastase); Chitosan—antipain (anti-trypsin);
Poly(acrylic acid)—bacitracin (anti-aminopeptidase N); Chitosan—EDTA (anti-
aminopeptidase N, anti-carboxypeptidase A); Chitosan—EDTA—antipain (anti-trypsin, anti-
chymotrypsin, anti-elastase).
Mucolytic and Mucus-Clearing Agents and Methods
Effective delivery of biotherapeutic agents via intranasal administration must take into
account the decreased drug transport rate across the protective mucus lining of the nasal
mucosa, in addition to drug loss due to binding to glycoproteins of the mucus layer. Normal
mucus is a viscoelastic, gel-like substance consisting of water, electrolytes, mucins,
macromolecules, and sloughed epithelial cells. It serves primarily as a cytoprotective and
lubricative covering for the underlying mucosal tissues. Mucus is secreted by randomly
distributed secretory cells located in the nasal epithelium and in other mucosal epithelia. The
structural unit of mucus is mucin. This glycoprotein is mainly responsible for the viscoelastic
nature of mucus, although other macromolecules may also contribute to this property. In
airway mucus, such macromolecules include locally produced secretory IgA, IgM, IgE,
lysozyme, and bronchotransferrin, which also play an important role in host defense
mechanisms.
The coordinate administration methods of the instant invention optionally incorporate
effective mucolytic or mucus-clearing agents, which serve to degrade, thin or clear mucus
from intranasal mucosal surfaces to facilitate absorption of intranasally administered
biotherapeutic agents. Within these methods, a mucolytic or mucus-clearing agent is
coordinately administered as an adjunct compound to enhance intranasal delivery of the
biologically active agent. Alternatively, an effective amount of a mucolytic or mucus-
clearing agent is incorporated as a processing agent within a multi-processing method of the
invention, or as an additive within a combinatorial formulation of the invention, to provide an
improved formulation that enhances intranasal delivery of biotherapeutic compounds by
reducing the barrier effects of intranasal mucus.
A variety of mucolytic or mucus-clearing agents are available for incorporation within
the methods and compositions of the invention. Based on their mechanisms of action,
mucolytic and mucus clearing agents can often be classified into the following groups:
proteases (e.g., pronase, papain) that cleave the protein core of mucin glycoproteins;
sulfhydryl compounds that split mucoprotein disulfide linkages; and detergents (e.g., Triton
X-100, Tween 20) that break non-covalent bonds within the mucus. Additional compounds in
this context include, but are not limited to, bile salts and surfactants, for example, sodium
deoxycholate, sodium taurodeoxycholate, sodium glycocholate, and lysophosphatidylcholine.
The effectiveness of bile salts in causing structural breakdown of mucus is in the
order deoxycholate > taurocholate > glycocholate. Other effective agents that reduce mucus
viscosity or adhesion to enhance intranasal delivery according to the methods of the invention
include, e.g., short-chain fatty acids, and mucolytic agents that work by chelation, such as N-
acylcollagen peptides, bile acids, and saponins (the latter function in part by chelating Ca2+
and/or Mg2+ which play an important role in maintaining mucus layer structure).
Additional mucolytic agents for use within the methods and compositions of the
invention include N-acetyl-L-cysteine (ACS), a potent mucolytic agent that reduces both the
viscosity and adherence of bronchopulmonary mucus and is reported to modestly increase
nasal bioavailability of human growth hormone in anesthetized rats (from 7.5 to 12.2%).
These and other mucolytic or mucus-clearing agents are contacted with the nasal mucosa,
typically in a concentration range of about 0.2 to 20 raM, coordinately with administration of
the biologically active agent, to reduce the polar viscosity and/or elasticity of intranasal
mucus.
Still other mucolytic or mucus-clearing agents may be selected from a range of
glycosidase enzymes, which are able to cleave glycosidic bonds within the mucus
glycoprotein. a-amylase and ß-amylase are representative of this class of enzymes, although
their mucolytic effect may be limited. In contrast, bacterial glycosidases which allow these
microorganisms to permeate mucus layers of their hosts.
For combinatorial use with most biologically active agents within the invention,
including peptide and protein therapeutics, non-ionogenic detergents are generally also useful
as mucolytic or mucus-clearing agents. These agents typically will not modify or
substantially impair the activity of therapeutic polypeptides.
Ciliostatic Agents and Methods
Because the self-cleaning capacity of certain mucosal tissues (e.g., nasal mucosal
tissues) by mucociliary clearance is necessary as a protective function (e.g., to remove dust,
allergens, and bacteria), it has been generally considered that this function should not be
substantially impaired by mucosal medications. Mucociliary transport in the respiratory tract
is a particularly important defense mechanism against infections. To achieve this function,
ciliary beating in the nasal and airway passages moves a layer of mucus along the mucosa to
removing inhaled particles and microorganisms.
Ciliostatic agents find use within the methods and compositions of the invention to
increase the residence time of mucosallv (e.g., intranasally) administered Y2 receptor-binding
peptide, analogs and mimetics, and other biologically active agents disclosed herein. In
particular, the delivery these agents within the methods and compositions of the invention is
significantly enhanced in certain aspects by the coordinate administration or combinatorial
formulation of one or more ciliostatic agents that function to reversibly inhibit ciliary activity
of mucosal cells, to provide for a temporary, reversible increase in the residence time of the
mucosally administered active agent(s). For use within these aspects of the invention, the
foregoing ciliostatic factors, either specific or indirect in their activity, are all candidates for
successful employment as ciliostatic agents in appropriate amounts (depending on
concentration, duration and mode of delivery) such that they yield a transient (i.e., reversible)
reduction or cessation of mucociliary clearance at a mucosal site of administration to enhance
delivery of Y2 receptor-binding peptide, analogs and mimetics, and other biologically active
agents disclosed herein, without unacceptable adverse side effects.
Within more detailed aspects, a specific ciliostatic factor is employed in a combined
formulation or coordinate administration protocol with one or more Y2 receptor-binding
peptide proteins, analogs and mimetics, and/or other biologically active agents disclosed
herein. Various bacterial ciliostatic factors isolated and characterized in the literature may be
employed within these embodiments of the invention. Ciliostatic factors from the bacterium
Pseudomonas aeruGlnosa include a phenazine derivative, a pyo compound (2-alkyl-4-
hydroxyquinolines), and a rhamnolipid (also known as a hemolysin). The pyo compound
produced ciliostasis at concentrations of 50 µg/ml and without obvious ultrastructural lesions.
The phenazine derivative also inhibited ciliary motility but caused some membrane
disruption, although at substantially greater concentrations of 400 µg/ml. Limited exposure
of tracheal explants to the rhamnolipid resulted in ciliostasis, which was associated with
altered ciliary membranes. More extensive exposure to rhamnolipid was associated with
removal of dynein arms from axonemes.
Surface Active Agents and Methods
Within more detailed aspects of the invention, one or more membrane penetration-
enhancing agents may be employed within a mucosal delivery method or formulation of the
invention to enhance mucosal delivery of Y2 receptor-binding peptide proteins, analogs and
mimetics, and other biologically active agents disclosed herein. Membrane penetration
enhancing agents in this context can be selected from: (i) a surfactant, (ii) a bile salt, (ii) a
phospholipid additive, mixed micelle, liposome, or carrier, (iii) an alcohol, (iv) an enamine,
(v) an NO donor compound, (vi) a long-chain amphipathic molecule (vii) a small
hydrophobic penetration enhancer; (viii) sodium or a salicylic acid derivative; (ix) a glycerol
ester of acetoacetic acid (x) a clyclodextrin or beta-cyclodextrin derivative, (xi) a medium-
chain fatty acid, (xii) a chelating agent, (xiii) an amino acid or salt thereof, (xiv) an N-
acetylamino acid or salt thereof, (xv) an enzyme degradative to a selected membrane
component, (ix) an inhibitor of fatty acid synthesis, or (x) an inhibitor of cholesterol
synthesis; or (xi) any combination of the membrane penetration enhancing agents recited in
(i)-(x).
Certain surface-active agents are readily incorporated within the mucosal delivery
formulations and methods of the invention as mucosal absorption enhancing agents. These
agents, which may be coordinately administered or combinatorially formulated with Y2
receptor-binding peptide proteins, analogs and mimetics, and other biologically active agents
disclosed herein, may be selected from a broad assemblage of known surfactants.
Surfactants, which generally fall into three classes: (1) nonionic polyoxyethylene ethers; (2)
bile salts such as sodium glycocholate (SGC) and deoxycholate (DOC); and (3) derivatives of
fusidic acid such as sodium taurodihydrofusidate (STDHF). The mechanisms of action of
these various classes of surface active agents typically include solubilization of the
biologically active agent. For proteins and peptides which often form aggregates, the surface
active properties of these absorption promoters can allow interactions with proteins such that
smaller units such as surfactant coated monomers may be more readily maintained in
solution. Examples of other surface-active agents are L-a-Phospharidycholine Didecanoyl
(DDPC) polysorbate 80 and polysorbate 20.These monomers are presumably more
transportable units than aggregates. A second potential mechanism is the protection of the
peptide or protein from proteolytic degradation by proteases in the mucosal environment.
Both bile salts and some fusidic acid derivatives reportedly inhibit proteolytic degradation of
proteins by nasal homogenates at concentrations less than or equivalent to those required to
enhance protein absorption. This protease inhibition may be especially important for
peptides with short biological half-lives.
Degradation Enzymes and Inhibitors of Fatty Acid and Cholesterol Synthesis
In related aspects of the invention, Y2 receptor-binding peptide proteins, analogs and
mimetics, and other biologically active agents for mucosal administration are formulated or
coordinately administered with a penetration enhancing agent selected from a degradation
enzyme, or a metabolic stimulatory agent or inhibitor of synthesis of fatty acids, sterols or
other selected epithelial barrier components, U.S. Patent No. 6,190,894. For example,
degradative enzymes such as phospholipase, hyaluronidase, neuraminidase, and
chondroitinase may be employed to enhance mucosal penetration of Y2 receptor-binding
peptide proteins, analogs and mimetics, and other biologically active agent without causing
irreversible damage to the mucosal barrier. In one embodiment, chondroitinase is employed
within a method or composition as provided herein to alter glycoprotein or glycolipid
constituents of the permeability barrier of the mucosa, thereby enhancing mucosal absorption
of Y2 receptor-binding peptide proteins, analogs and mimetics, and other biologically active
agents disclosed herein.
With regard to inhibitors of synthesis of mucosal barrier constituents, it is noted that
free fatty acids account for 20-25% of epithelial lipids by weight. Two rate-limiting enzymes
in the biosynthesis of free fatty acids are acetyl CoA carboxylase and fatty acid synthetase.
Through a series of steps, free fatty acids are metabolized into phospholipids. Thus,
inhibitors of free fatty acid synthesis and metabolism for use within the methods and
compositions of the invention include, but are not limited to, inhibitors of acetyl CoA
carboxylase such as 5-tetradecyloxy-2-furancarboxylic acid (TOFA); inhibitors of fatty acid
synthetase; inhibitors of phospholipase A such as gomisin A, 2-(p-amylcinnamyl)amino-4-
chlorobenzoic acid, bromophenacyl bromide, monoalide, 7,7-dimethyl-5,8-eicosadienoic
acid, nicergoline, cepharanthine, nicardipine, quercetin, dibutyryl-cyclic AMP, R-24571, N-
oleoylethanolamine, N-(7-nitro-2,l,3-benzoxadiazol-4-yl) phosphostidyl serine, cyclosporine
A, topical anesthetics, including dibucaine, prenylamine, retinoids, such as all-trans and 13-
cis-retinoic acid, W-7, trifluoperazine, R-24571 (calmidazolium), l-hexadocyl-3-
trifluoroethyl glycero-sn-2-phosphomenthol (MJ33); calcium channel blockers including
nicardipine, verapamil, diltiazem, nifedipine, and nimodipine; antimalarials including
quinacrine, mepacrine, chloroquine and hydroxychloroquine; beta blockers including
propanalol and labetalol; calmodulin antagonists; EGTA; thimersol; glucocorticosteroids
including dexamethasone and prednisolone; and nonsteroidal antiinflammatory agents
including indomethacin and naproxen.
Free sterols, primarily cholesterol, account for 20-25% of the epithelial lipids by
weight. The rate limiting enzyme in the biosynthesis of cholesterol is 3-hydroxy-3-
methylglutaryl (HMG) CoA reductase. Inhibitors of cholesterol synthesis for use within the
methods and compositions of the invention include, but are not limited to, competitive
inhibitors of (HMG) CoA reductase, such as simvastatin, lovastatin, fluindostatin
(fluvastatin), pravastatin, mevastatin, as well as other HMG CoA reductase inhibitors, such as
cholesterol oleate, cholesterol sulfate and phosphate, and oxygenated sterols, such as 25-OH--
and 26-OH-- cholesterol; inhibitors of squalene synthetase; inhibitors of squalene epoxidase;
inhibitors of DELTA7 or DELTA24 reductases such as 22,25-diazacholesterol, 20,25-
diazacholestenol, AY9944, and triparanol.
Each of the inhibitors of fatty acid synthesis or the sterol synthesis inhibitors may be
coordinately administered or combinatorially formulated with one or more Y2 receptor-
binding peptide proteins, analogs and mimetics, and other biologically active agents disclosed
herein to achieve enhanced epithelial penetration of the active agent(s). An effective
concentration range for the sterol inhibitor in a therapeutic or adjunct formulation for
mucosal delivery is generally from about 0.0001% to about 20% by weight of the total, more
typically from about 0.01% to about 5%.
Nitric Oxide Donor Agents and Methods
Within other related aspects of the invention, a nitric oxide (NO) donor is selected as
a membrane penetration-enhancing agent to enhance mucosal delivery of one or more Y2
receptor-binding peptide proteins, analogs and mimetics, and other biologically active agents
disclosed herein. Various NO donors are known in the art and are useful in effective
concentrations within the methods and formulations of the invention. Exemplary NO donors
include, but are not limited to, nitroglycerine, nitropruside, NOC5 [3-(2-hydroxy-l -(methyl-
ethyl)-2-nitrosohydrazino)-1-propanamine], NOC12 [N-ethyl-2-(1-ethyl-hydroxy-2-
nitrosohydrazino)-ethanamine], SNAP [S-nitroso-N-acetyl-DL-penicillamine], NORI and
NOR4. Within the methods and compositions of the invention, an effective amount of a
selected NO donor is coordinately administered or combinatorially formulated with one or
more Y2 receptor-binding peptide proteins, analogs and mimetics, and/or other biologically
active agents disclosed herein, into or through the mucosal epithelium.
Agents for Modulating Epithelial Junction Structure and/or Physiology
The present invention provides pharmaceutical composition that contains one or more
Y2 receptor-binding peptide proteins, analogs or mimetics, and/or other biologically active
agents in combination with mucosal delivery enhancing agents disclosed herein formulated in
a pharmaceutical preparation for mucosal delivery.
The permeabilizing agent reversibly enhances mucosal epithelial paracellular
transport, typically by modulating epithelial junctional structure and/or physiology at a
mucosal epithelial surface in the subject. This effect typically involves inhibition by the
permeabilizing agent of homotypic or heterotypic binding between epithelial membrane
adhesive proteins of neighboring epithelial cells. Target proteins for this blockade of
homotypic or heterotypic binding can be selected from various related junctional adhesion
molecules (JAMs), occludins, or claudins.
In yet additional detailed embodiments, the invention provides permeabilizing
peptides and peptide analogs and mimetics for enhancing mucosal epithelial paracellular
transport. The subject peptides and peptide analogs and mimetics typically work within the
compositions and methods of the invention by modulating epithelial junctional structure
and/or physiology in a mammalian subject. In certain embodiments, the peptides and peptide
analogs and mimetics effectively inhibit homotypic and/or heterotypic binding of an
epithelial membrane adhesive protein selected from a junctional adhesion molecule (JAM),
occludin, or claudin.
One such agent that has been extensively studied is the bacterial toxin from Vibrio
cholerae known as the "zonula occludens toxin" (ZOT). This toxin mediates increased
intestinal mucosal permeability and causes disease symptoms including diarrhea in infected
subjects. Fasano et al, Proc. Nat. Acad. Sci., U.S.A., 8:5242-5246 (1991). When tested on
rabbit ileal mucosa, ZOT increased the intestinal permeability by modulating the structure of
intercellular tight junctions. More recently, it has been found that ZOT is capable of
reversibly opening tight junctions in the intestinal mucosa. It has also been reported that
ZOT is capable of reversibly opening tight junctions in the nasal mucosa. U.S. Pat No.
5,908,825.
Within the methods and compositions of the invention, ZOT, as well as various
analogs and mimetics of ZOT that function as agonists or antagonists of ZOT activity, are
useful for enhancing intranasal delivery of biologically active agents—by increasing
paracellular absorption into and across the nasal mucosa. In this context, ZOT typically acts
by causing a structural reorganization of tight junctions marked by altered localization of the
junctional protein ZO1. Within these aspects of the invention, ZOT is coordinately
administered or combinatorially formulated with the biologically active agent in an effective
amount to yield significantly enhanced absorption of the active agent, by reversibly
increasing nasal mucosal permeability without substantial adverse side effects
Vasodilator Agents and Methods
Yet another class of absorption-promoting agents that shows beneficial utility within
the coordinate administration and combinatorial formulation methods and compositions of
the invention are vasoactive compounds, more specifically vasodilators. These compounds
function within the invention to modulate the structure and physiology of the submucosal
vasculature, increasing the transport rate of Y2 receptor-binding peptide, analogs and
mimetics, and other biologically active agents into or through the mucosal epithelium and/or
to specific target tissues or compartments (e.g., the systemic circulation or central nervous
system.).
Vasodilator agents for use within the invention typically cause submucosal blood
vessel relaxation by either a decrease in cytoplasmic calcium, an increase in nitric oxide (NO)
or by inhibiting myosin light chain kinase. They are generally divided into 9 classes: calcium
antagonists, potassium channel openers, ACE inhibitors, angiotensin-II receptor antagonists,
a-adrenergic and imidazole receptor antagonists, b1 -adrenergic agonists, phosphodiesterase
inhibitors, eicosanoids and NO donors.
Despite chemical differences, the pharmacokinetic properties of calcium antagonists
are similar. Absorption into the systemic circulation is high, and these agents therefore
undergo considerable first-pass metabolism by the liver, resulting in individual variation in
pharmacokinetics. Except for the newer drugs of the dihydropyridine type (amlodipine,
felodipine, isradipine, nilvadipine, nisoldipine and nitrendipine), the half-life of calcium
antagonists is short. Therefore, to maintain an effective drug concentration for many of these
may require delivery by multiple dosing, or controlled release formulations, as described
elsewhere herein. Treatment with the potassium channel opener minoxidil may also be
limited in manner and level of administration due to potential adverse side effects.
ACE inhibitors prevent conversion of angiotensin-I to angiotensin-II, and are most
effective when renin production is increased. Since ACE is identical to kininase-II, which
inactivates the potent endogenous vasodilator bradykinin, ACE inhibition causes a reduction
in bradykinin degradation. ACE inhibitors provide the added advantage of cardioprotective
and cardioreparative effects, by preventing and reversing cardiac fibrosis and ventricular
hypertrophy in animal models. The predominant elimination pathway of most ACE
inhibitors is via renal excretion. Therefore, renal impairment is associated with reduced
elimination and a dosage reduction of 25 to 50% is recommended in patients with moderate
to severe renal impairment.
With regard to NO donors, these compounds are particularly useful within the
invention for their additional effects on mucosal permeability. In addition to the above-noted
NO donors, complexes of NO with nucleophiles called NO/nucleophiles, or NONOates,
spontaneously and nonenzymatically release NO when dissolved in aqueous solution at
physiologic pH. . In contrast, nitro vasodilators such as nitroglycerin require specific
enzyme activity for NO release. NONOates release NO with a defined stoichiometry and at
predictable rates ranGlng from diethylenetriamine/NO (DETANO).
Within certain methods and compositions of the invention, a selected vasodilator
agent is coordinately administered (e.g., systemically or intranasally, simultaneously or in
combinatorially effective temporal association) or combinatorially formulated with one or
more Y2 receptor-binding peptide, analogs and mimetics, and other biologically active
agent(s) in an amount effective to enhance the mucosal absorption of the active agent(s) to
reach a target tissue or compartment in the subject (e.g., the liver, hepatic portal vein, CNS
tissue or fluid, or blood plasma).
Selective Transport-Enhancing Agents and Methods
The compositions and delivery methods of the invention optionally incorporate a
selective transport-enhancing agent that facilitates transport of one or more biologically
active agents. These transport-enhancing agents may be employed in a combinatorial
formulation or coordinate administration protocol with one or more of the Y2 receptor-
binding peptide proteins, analogs and mimetics disclosed herein, to coordinately enhance
delivery of one or more additional biologically active agent(s) across mucosal transport
barriers, to enhance mucosal delivery of the active agent(s) to reach a target tissue or
compartment in the subject (e.g., the mucosal epithelium, liver, CNS tissue or fluid, or blood
plasma). Alternatively, the transport-enhancing agents may be employed in a combinatorial
formulation or coordinate administration protocol to directly enhance mucosal delivery of
one or more of the Y2 receptor-binding peptide proteins, analogs and mimetics, with or
without enhanced delivery of an additional biologically active agent.
Exemplary selective transport-enhancing agents for use within this aspect of the
invention include, but are not limited to, glycosides, sugar-containing molecules, and binding
agents such as lectin binding agents, which are known to interact specifically with epithelial
transport barrier components. For example, specific "bioadhesive" ligands, including various
plant and bacterial lectins, which bind to cell surface sugar moieties by receptor-mediated
interactions can be employed as carriers or conjugated transport mediators for enhancing
mucosal, e.g., nasal delivery of biologically active agents within the invention. Certain
bioadhesive ligands for use within the invention will mediate transmission of biological
signals to epithelial target cells that trigger selective uptake of the adhesive ligand by
specialized cellular transport processes (endocytosis or transcytosis). These transport
mediators can therefore be employed as a "carrier system" to stimulate or direct selective
uptake of one or more Y2 receptor-binding peptide proteins, analogs and mimetics, and other
biologically active agent(s) into and/or through mucosal epithelia. These and other selective
transport-enhancing agents significantly enhance mucosal delivery of macromolecular
biopharmaceuticals (particularly peptides, proteins, oligonucleotides and polynucleotide
vectors) within the invention. Lectins are plant proteins that bind to specific sugars found on
the surface of glycoproteins and glycolipids of eukaryotic cells. Concentrated solutions of
lectins have a 'mucotractive' effect, and various studies have demonstrated rapid receptor
mediated endocytocis (RME) of lectins and lectin conjugates (e.g., concanavalin A
conjugated with colloidal gold particles) across mucosal surfaces. Additional studies have
reported that the uptake mechanisms for lectins can be utilized for intestinal drug targeting in
vivo. In certain of these studies, polystyrene nanoparticles (500 nm) were covalently coupled
to tomato lectin and reported yielded improved systemic uptake after oral administration to
rats.
In addition to plant lectins, microbial adhesion and invasion factors provide a rich
source of candidates for use as adhesive/selective transport carriers within the mucosal
delivery methods and compositions of the invention. Two components are necessary for
bacterial adherence processes, a bacterial 'adhesin' (adherence or colonization factor) and a
receptor on the host cell surface. Bacteria causing mucosal infections need to penetrate the
mucus layer before attaching themselves to the epithelial surface. This attachment is usually
mediated by bacterial fimbriae or pilus structures, although other cell surface components
may also take part in the process. Adherent bacteria colonize mucosal epithelia by
multiplication and initiation of a series of biochemical reactions inside the target cell through
signal transduction mechanisms (with or without the help of toxins). Associated with these
invasive mechanisms, a wide diversity of bioadhesive proteins (e.g., invasin, internalin)
oriGlnally produced by various bacteria and viruses are known. These allow for extracellular
attachment of such microorganisms with an impressive selectivity for host species and even
particular target tissues. Signals transmitted by such receptor-ligand interactions trigger the
transport of intact, living microorganisms into, and eventually through, epithelial cells by
endo- and transcytotic processes. Such naturally occurring phenomena may be harnessed
(e.g., by complexing biologically active agents such as Y2 receptor-binding peptide with an
adhesin) according to the teachings herein for enhanced delivery of biologically active
compounds into or across mucosal epithelia and/or to other designated target sites of drug
action.
Various bacterial and plant toxins that bind epithelial surfaces in a specific, lectin-like
manner are also useful within the methods and compositions of the invention. For example,
diptheria toxin (DT) enters host cells rapidly by RME. Likewise, the B subunit of the E. coli
heat labile toxin binds to the brush border of intestinal epithelial cells in a highly specific,
lectin-like manner. Uptake of this toxin and transcytosis to the basolateral side of the
enterocytes has been reported in vivo and in vitro. Other researches have expressed the
transmembrane domain of diphtheria toxin in E. coli as a maltose-binding fusion protein and
coupled it chemically to high-Mw poly-L-lysine. The resulting complex was successfully
used to mediate internalization of a reporter gene in vitro. in addition to these examples,
Staphylococcus aureus produces a set of proteins (e.g., staphylococcal enterotoxin A (SEA),
SEB, toxic shock syndrome toxin 1 (TSST-1) which act both as superantigens and toxins.
Studies relating to these proteins have reported dose-dependent, facilitated transcytosis of
SEB and TSST-1 in Caco-2 cells.
Viral haemagglutinins comprise another type of transport agent to facilitate mucosal
delivery of biologically active agents within the methods and compositions of the invention.
The initial step in many viral infect ions is the binding of surface proteins (haemagglutinins)
to mucosal cells. These binding proteins have been identified for most viruses, including
rotaviruses, varicella zoster virus, semliki forest virus, adenoviruses, potato leafroll virus, and
reovirus. These and other exemplary viral hemagglutinins can be employed in a
combinatorial formulation (e.g., a mixture or conjugate formulation) or coordinate
administration protocol with one or more of the Y2 receptor-binding peptide, analogs and
mimetics disclosed herein, to coordinately enhance mucosal delivery of one or more
additional biologically active agent(s). Alternatively, viral hemagglutinins can be employed
in a combinatorial formulation or coordinate administration protocol to directly enhance
mucosal delivery of one or more of the Y2 receptor-binding peptide proteins, analogs and
mimetics, with or without enhanced delivery of an additional biologically active agent.
A variety of endogenous, selective transport-mediating factors are also available for
use within the invention. Mammalian cells have developed an assortment of mechanisms to
facilitate the internalization of specific substrates and target these to defined compartments.
Collectively, these processes of membrane deformations are termed 'endocytosis' and
comprise phagocytosis, pinocytosis, receptor-mediated endocytosis (clathrin-mediated RME),
and potocytosis (non-clathrin-mediated RME). RME is a highly specific cellular biologic
process by which, as its name implies, various ligands bind to cell surface receptors and are
subsequently internalized and trafficked within the cell. In many cells the process of
endocytosis is so active that the entire membrane surface is internalized and replaced in less
than a half hour. Two classes of receptors are proposed based on their orientation in the cell
membrane; the amino terminus of Type I receptors is located on the extracellular side of the
membrane, whereas Type II receptors have this same protein tail in the intracellular milieu.
Still other embodiments of the invention utilize transferrin as a carrier or stimulant of
RME of mucosally delivered biologically active agents. Transferrin, an 80 kDa iron-
transporting glycoprotein, is efficiently taken up into cells by RME. Transferrin receptors are
found on the surface of most proliferating cells, in elevated numbers on erythroblasts and on
many kinds of tumors. The transcytosis of transferrin (Tf) and transferrin conjugates is
reportedly enhanced in the presence of Brefeldin A (BFA), a fungal metabolite. In other
studies, BFA treatment has been reported to rapidly increase apical endocytosis of both ricin
and HRP in MDCK cells. Thus, BFA and other agents that stimulate receptor-mediated
transport can be employed within the methods of the invention as combinatorially formulated
(e.g., conjugated) and/or coordinately administered agents to enhance receptor-mediated
transport of biologically active agents, including Y2 receptor-binding peptide proteins,
analogs and mimetics.
Polymeric Delivery Vehicles and Methods
Within certain aspects of the invention, Y2 receptor-binding peptide proteins, analogs
and mimetics, other biologically active agents disclosed herein, and delivery-enhancing
agents as described above, are, individually or combinatorially, incorporated within a
mucosally (e.g., nasally) administered formulation that includes a biocompatible polymer
functioning as a carrier or base. Such polymer carriers include polymeric powders, matrices
or microparticulate delivery vehicles, among other polymer forms. The polymer can be of
plant, animal, or synthetic oriGln. Often the polymer is crosslinked. Additionally, in these
delivery systems the Y2 receptor-binding peptide, analog or mimetic, can be functionalized in
a manner where it can be covalently bound to the polymer and rendered inseparable from the
polymer by simple washing. In other embodiments, the polymer is chemically modified with
an inhibitor of enzymes or other agents which may degrade or inactivate the biologically
active agent(s) and/or delivery enhancing agent(s). In certain formulations, the polymer is a
partially or completely water insoluble but water swellable polymer, e.g., a hydrogel.
Polymers useful in this aspect of the invention are desirably water interactive and/or
hydrophilic in nature to absorb significant quantities of water, and they often form hydrogels
when placed in contact with water or aqueous media for a period of time sufficient to reach
equilibrium with water. In more detailed embodiments, the polymer is a hydrogel which,
when placed in contact with excess water, absorbs at least two times its weight of water at
equilibrium when exposed to water at room temperature, U.S. Patent No. 6,004,583.
Drug delivery systems based on biodegradable polymers are preferred in many
biomedical applications because such systems are broken down either by hydrolysis or by
enzymatic reaction into non-toxic molecules. The rat+e of degradation is controlled by
manipulating the composition of the biodegradable polymer matrix. These types of systems
can therefore be employed in certain settings for long-term release of biologically active
agents. Biodegradable polymers such as poly(glycolic acid) (PGA), poly-(lactic acid) (PLA),
and poly(D,L-lactic-co-glycolic acid) (PLGA), have received considerable attention as
possible drug delivery carriers, since the degradation products of these polymers have been
found to have low toxicity. During the normal metabolic function of the body these polymers
degrade into carbon dioxide and water. These polymers have also exhibited excellent
biocompatibility.
For prolonGlng the biological activity of Y2 receptor-binding peptide, analogs and
mimetics, and other biologically active agents disclosed herein, as well as optional delivery-
enhancing agents, these agents may be incorporated into polymeric matrices, e.g.,
polyorthoesters, polyanhydrides, or polyesters. This yields sustained activity and release of
the active agent(s), e.g., as determined by the degradation of the polymer matrix. Although
the encapsulation of biotherapeutic molecules inside synthetic polymers may stabilize them
during storage and delivery, the largest obstacle of polymer-based release technology is the
activity loss of the therapeutic molecules during the formulation processes that often involve
heat, sonication or organic solvents.
Absorption-promoting polymers contemplated for use within the invention may
include derivatives and chemically or physically modified versions of the foregoing types of
polymers, in addition to other naturally occurring or synthetic polymers, gums, resins, and
other agents, as well as blends of these materials with each other or other polymers, so long
as the alterations, modifications or blending do not adversely affect the desired properties,
such as water absorption, hydrogel formation, and/or chemical stability for useful application.
In more detailed aspects of the invention, polymers such as nylon, acrylan and other normally
hydrophobic synthetic polymers may be sufficiently modified by reaction to become water
swellable and/or form stable gels in aqueous media.
Absorption-promoting polymers of the invention may include polymers from the
group of homo- and copolymers based on various combinations of the following vinyl
monomers: acrylic and methacrylic acids, acrylamide, methacrylamide, hydroxyethylacrylate
or methacrylate, vinylpyrrolidones, as well as polyvinylalcohol and its co- and terpolymers,
polyvinylacetate, its co- and terpolymers with the above listed monomers and 2-acrylamido-
2-methyl-propanesulfonic acid (AMPS®). Very useful are copolymers of the above listed
monomers with copolymerizable functional monomers such as acryl or methacryl amide
acrylate or methacrylate esters where the ester groups are derived from straight or branched
chain alkyl, aryl having up to four aromatic rings which may contain alkyl substituents of 1 to
6 carbons; steroidal, sulfates, phosphates or cationic monomers such as N,N-
dimethylaminoalkyl(meth)acrylamide, dimethylaminoalkyl(meth)acrylate,
(meth)acryloxyalkyltrimethylammonium chloride, (meth)acryloxyalkyldimethylbenzyl
ammonium chloride.
Additional absorption-promoting polymers for use within the invention are those
classified as dextrans, dextrins, and from the class of materials classified as natural gums and
resins, or from the class of natural polymers such as processed collagen, chitin, chitosan,
pullalan, zooglan, alGlnates and modified alGlnates such as "Kelcoloid" (a polypropylene
glycol modified alGlnate) gellan gums such as "Kelocogel", Xanathan gums such as
'Keltrol", estastin, alpha hydroxy butyrate and its copolymers, hyaluronic acid and its
derivatives, polylactic and glycolic acids.
A very useful class of polymers applicable within the instant invention are
olefinically-unsaturated carboxylic acids containing at least one activated carbon-to-carbon
olefinic double bond, and at least one carboxyl group; that is, an acid or functional group
readily converted to an acid containing an olefinic double bond which readily functions in
polymerization because of its presence in the monomer molecule, either in the alpha-beta
position with respect to a carboxyl group, or as part of a terminal methylene grouping.
Olefinically-unsaturated acids of this class include such materials as the acrylic acids typified
by the acrylic acid itself, alpha-cyano acrylic acid, beta methylacrylic acid (crotonic acid),
alpha-phenyl acrylic acid, beta-acryloxy propionic acid, cinnamic acid, p-chloro cinnamic
acid, l-carboxy-4-phenyl butadiene-1,3, itaconic acid, citraconic acid, mesaconic acid,
glutaconic acid, aconitic acid, maleic acid, fumaric acid, and tricarboxy ethylene. As used
herein, the term "carboxylic acid" includes the polycarboxylic acids and those acid
anhydrides, such as maleic anhydride, wherein the anhydride group is formed by the
elimination of one molecule of water from two carboxyl groups located on the same
carboxylic acid molecule.
Representative acrylates useful as absorption-promoting agents within the invention
include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate,
isobutyl acrylate, methyl methacrylate, methyl ethacrylate, ethyl methacrylate, octyl acrylate,
heptyl acrylate, octyl methacrylate, isopropyl methacrylate, 2-ethylhexyl methacrylate, nonyl
acrylate, hexyl acrylate, n-hexyl methacrylate, and the like. Higher alkyl acrylic esters are
decyl acrylate, isodecyl methacrylate, lauryl acrylate, stearyl acrylate, behenyl acrylate and
melissyl acrylate and methacrylate versions thereof. Mixtures of two or three or more long
chain acrylic esters may be successfully polymerized with one of the carboxylic monomers.
Other comonomers include olefins, including alpha olefins, vinyl ethers, vinyl esters, and
mixtures thereof.
Other vinylidene monomers, including the acrylic nitriles, may also be used as
absorption-promoting agents within the methods and compositions of the invention to
enhance delivery and absorption of one or more Y2 receptor-binding peptide proteins,
analogs and mimetics, and other biologically active agent(s), including to enhance delivery of
the active agent(s) to a target tissue or compartment in the subject (e.g., the liver, hepatic
portal vein, CNS tissue or fluid, or blood plasma). Useful alpha, beta-olefinically unsaturated
nitriles are preferably monoolefinically unsaturated nitriles having from 3 to 10 carbon atoms
such as acrylonitrile, methacrylonitrile, and the like. Most preferred are acrylonitrile and
methacrylonitrile. Acrylic amides containing from 3 to 35 carbon atoms including
monoolefinically unsaturated amides also may be used. Representative amides include
acrylamide, methacrylamide, N-t-butyl acrylamide, N-cyclohexyl acrylamide, higher alkyl
amides, where the alkyl group on the nitrogen contains from 8 to 32 carbon atoms, acrylic
amides including N-alkylol amides of alpha, beta-olefinically unsaturated carboxylic acids
including those having from 4 to 10 carbon atoms such as N-methylol acrylamide, N-
propanol acrylamide, N-methylol methacrylamide, N-methylol maleimide, N-methylol
maleamic acid esters, N-methylol-ß-vinyl benzamide, and the like.
Yet additional useful absorption promoting materials are alpha-olefins containing
from 2 to 18 carbon atoms, more preferably from 2 to 8 carbon atoms; dienes containing from
4 to 10 carbon atoms; vinyl esters and allyl esters such as vinyl acetate; vinyl aromatics such
as styrene, methyl styrene and chloro-styrene; vinyl and allyl ethers and ketones such as vinyl
methyl ether and methyl vinyl ketone; chloroacrylates; cyanoalkyl acrylates such as alpha-
cyanomethyl acrylate, and the alpha-, beta-, and gamma-cyanopropyl acrylates;
alkoxyacrylates such as methoxy ethyl acrylate; haloacrylates as chloroethyl acrylate; vinyl
halides and vinyl chloride, vinylidene chloride and the like; divinyls, diacrylates and other
polyfunctional monomers such as divinyl ether, diethylene glycol diacrylate, ethylene glycol
dimethacrylate, methylene-bis-acrylamide, allylpentaerythritol, and the like; and bis (beta-
haloalkyl) alkenyl phosphonates such as bis(beta-chloroethyl) vinyl phosphonate and the like
as are known to those skilled in the art. Copolymers wherein the carboxy containing
monomer is a minor constituent, and the other vinylidene monomers present as major
components are readily prepared in accordance with the methods disclosed herein.
When hydrogels are employed as absorption promoting agents within the invention,
these may be composed of synthetic copolymers from the group of acrylic and methacrylic
acids, acrylamide, methacrylamide, hydroxyethylacrylate (HEA) or methacrylate (HEMA),
and vinylpyrrolidones which are water interactive and swellable. Specific illustrative
examples of useful polymers, especially for the delivery of peptides or proteins, are the
following types of polymers: (meth)acrylamide and 0.1 to 99 wt. % (meth)acrylic acid;
(meth)acrylamides and 0.1-75 wt % (meth)acryloxyethyl trimethyammonium chloride;
(meth)acrylamide and 0.1-75 wt % (meth)acrylamide; acrylic acid and 0.1-75 wt %
alkyl(meth)acrylates; (meth)acrylamide and 0.1-75 wt % AMPS.RTM. (trademark of
Lubrizol Corp.); (meth)acrylamide and 0 to 30 wt % alkyl(meth)acrylamides and 0.1-75 wt %
AMPS.RTM.; (meth)acrylamide and 0.1-99 wt. % HEMA; (metb)acrylamide and 0.1 to 75
wt % HEMA and 0.1 to 99%(meth)acrylic acid; (meth)acrylic acid and 0.1-99 wt % HEMA;
50 mole % vinyl ether and 50 mole % maleic anhydride; (meth)acrylamide and 0.1 to 75 wt
% (meth)acryloxyalky dimethyl benzylammonium chloride; (meth)acrylamide and 0.1 to 99
wt % vinyl pyrrolidone; (meth)acrylamide and 50 wt % vinyl pyrrolidone and 0.1-99.9 wt %
(meth)acrylic acid; (meth)acrylic acid and 0.1 to 75 wt % AMPS.RTM. and 0.1-75 wt %
alkyl(meth)acrylamide. In the above examples, alkyl means C1 to C30, preferably C1 to C22,
linear and branched and C4 to C16 cyclic; where (meth) is used, it means that the monomers
with and without the methyl group are included. Other very useful hydrogel polymers are
swellable, but insoluble versions of poly(vinyl pyrrolidone) starch, carboxymethyl cellulos
and polyvinyl alcohol.
Additional polymeric hydrogel materials useful within the invention include (poly)
hydroxyalkyl (meth)acrylate: anionic and cationic hydro gels: poly(electrolyte) complexes;
poly(vinyl alcohols) having a low acetate residual: a swellable mixture of crosslinked agar
and crosslinked carboxymethyl cellulose: a swellable composition comprising methyl
cellulose mixed with a sparingly crosslinked agar; a water swellable copolymer produced by
a dispersion of finely divided copolymer of maleic anhydride with styrene, ethylene,
propylene, or isobutylene; a water swellable polymer of N-vinyl lactams; swellable sodium
salts of carboxymethyl cellulose; and the like.
Other gelable, fluid imbibing and retaining polymers useful for forming the
hydrophilic hydrogel for mucosal delivery of biologically active agents within the invention
include pectin; polysaccharides such as agar, acacia, karaya, tragacenth, alGlns and guar and
their crosslinked versions; acrylic acid polymers, copolymers and salt derivatives,
polyacrylamides; water swellable indene maleic anhydride polymers; starch graft
copolymers; acrylate type polymers and copolymers with water absorbability of about 2 to
400 times its oriGlnal weight; diesters of polyglucan; a mixture of crosslinked poly(vinyl
alcohol) and poly(N-vinyl-2-pyrrolidone); polyoxybutylene-polyethylene block copolymer
gels; carob gum; polyester gels; poly urea gels; polyether gels; polyamide gels; polyimide
gels; polypeptide gels; polyamino acid gels; poly cellulosic gels; crosslinked indene-maleic
anhydride acrylate polymers; and polysaccharides.
Synthetic hydrogel polymers for use within the invention may be made by an infinite
combination of several monomers in several ratios. The hydrogel can be crosslinked and
generally possesses the ability to imbibe and absorb fluid and swell or expand to an enlarged
equilibrium state. The hydrogel typically swells or expands upon delivery to the nasal
mucosal surface, absorbing about 2-5, 5-10, 10-50, up to 50-100 or more times fold its weight
of water. The optimum degree of swellability for a given hydrogel will be determined for
different biologically active agents depending upon such factors as molecular weight, size,
solubility and diffusion characteristics of the active agent carried by or entrapped or
encapsulated within the polymer, and the specific spacing and cooperative chain motion
associated with each individual polymer.
Hydrophilic polymers useful within the invention are water insoluble but water
swellable. Such water-swollen polymers as typically referred to as hydrogels or gels. Such
gels may be conveniently produced from water-soluble polymer by the process of
crosslinking the polymers by a suitable crosslinking agent. However, stable hydrogels may
also be formed from specific polymers under defined conditions of pH, temperature and/or
ionic concentration, according to know methods in the art. Typically the polymers are cross-
linked, that is, cross-linked to the extent that the polymers possess good hydrophilic
properties, have improved physical integrity (as compared to non cross-linked polymers of
the same or similar type) and exhibit improved ability to retain within the gel network both
the biologically active agent of interest and additional compounds for coadministration
therewith such as a cytokine or enzyme inhibitor, while retaining the ability to release the
active agent(s) at the appropriate location and time.
Generally hydrogel polymers for use within the invention are crosslinked with a
difunctional cross-linking in the amount of from 0.01 to 25 weight percent, based on the
weight of the monomers forming the copolymer, and more preferably from 0.1 to 20 weight
percent and more often from 0. 1 to 15 weight percent of the crosslinking agent. Another
useful amount of a crosslinking agent is 0.1 to 10 weight percent. Tri, tetra or higher
multifunctional crosslinking agents may also be employed. When such reagents are utilized,
lower amounts may be required to attain equivalent crosslinking density, i.e., the degree of
crosslinking, or network properties that are sufficient to contain effectively the biologically
active agent(s).
The crosslinks can be covalent, ionic or hydrogen bonds with the polymer possessing
the ability to swell in the presence of water containing fluids. Such crosslinkers and
crosslinking reactions are known to those skilled in the art and in many cases are dependent
upon the polymer system. Thus a crosslinked network may be formed by free radical
copolymerization of unsaturated monomers. Polymeric hydrogels may also be formed by
crosslinking preformed polymers by reacting functional groups found on the polymers such
as alcohols, acids, amines with such groups as glyoxal, formaldehyde or glutaraldehyde, bis
anhydrides and the like.
The polymers also may be cross-linked with any polyene, e.g. decadiene or trivinyl
cyclohexane; acrylamides, such as N,N-methylene-bis (acrylamide); polyfunctional acrylates,
such as trimethylol propane triacrylate; or polyfunctional vinylidene monomer containing at
least 2 terminal CH2 allyl acrylates and the like, In certain embodiments, cross-linking monomers for use in
preparing the copolymers are polyalkenyl polyethers having more than one alkenyl ether
grouping per molecule, which may optionally possess alkenyl groups in which an olefinic
double bond is present attached to a terminal methylene grouping (e.g., made by the
etherification of a polyhydric alcohol containing at least 2 carbon atoms and at least 2
hydroxyl groups). Compounds of this class may be produced by reacting an alkenyl halide,
such as allyl chloride or allyl bromide, with a strongly alkaline aqueous solution of one or
more polyhydric alcohols. The product may be a complex mixture of polyethers with varying
numbers of ether groups. Efficiency of the polyether cross-linking agent increases with the
number of potentially polymerizable groups on the molecule. Typically, polyethers
containing an average of two or more alkenyl ether groupings per molecule are used. Other
cross-linking monomers include for example, diallyl esters, dimethallyl ethers, allyl or
methallyl acrylates and acrylamides, tetravinyl silane, polyalkenyl methanes, diacrylates. and
dimethacrylates, divinyl compounds such as divinyl benzene, polyallyl phosphate, diallyloxy
compounds and phosphite esters and the like. Typical agents are allyl pentaerythritol, allyl
sucrose, trimethylolpropane triacrylate, 1,6-hexanediol diacrylate, trimethylolpropane diallyl
ether, pentaerythritol triacrylate, tetramethylene dimethacrylate, ethylene diacrylate, ethylene
dimethacrylate, triethylene glycol dimethacrylate, and the like. Allyl pentaerythritol,
trimethylolpropane diallylether and allyl sucrose provide suitable polymers. When the cross-
linking agent is present, the polymeric mixtures usually contain between about 0.01 to 20
weight percent, e.g., 1%, 5%, or 10% or more by weight of cross-linking monomer based on
the total of carboxylic acid monomer, plus other monomers.
In more detailed aspects of the invention, mucosal delivery of Y2 receptor-binding
peptide, analogs and mimetics, and other biologically active agents disclosed herein, is
enhanced by retaining the active agent(s) in a slow-release or enzymatically or
physiologically protective carrier or vehicle, for example a hydrogel that shields the active
agent from the action of the degradative enzymes. In certain embodiments, the active agent
is bound by chemical means to the carrier or vehicle, to which may also be admixed or bound
additional agents such as enzyme inhibitors, cytokines, etc. The active agent may alternately
be immobilized through sufficient physical entrapment within the carrier or vehicle, e.g., a
polymer matrix.
Polymers such as hydrogels useful within the invention may incorporate functional
linked agents such as glycosides chemically incorporated into the polymer for enhancing
intranasal bioavailability of active agents formulated therewith. Examples of such glycosides
are glucosides, fructosides, galactosides, arabinosides, mannosides and their alkyl substituted
derivatives and natural glycosides such as arbutin, phlorizin, amygdalin, digitonin, saponin,
and indican. There are several ways in which a typical glycoside may be bound to a polymer.
For example, the hydrogen of the hydroxyl groups of a glycoside or other similar
carbohydrate may be replaced by the alkyl group from a hydrogel polymer to form an ether.
Also, the hydroxyl groups of the glycosides may be reacted to esterify the carboxyl groups of
a polymeric hydrogel to form polymeric esters in situ. Another approach is to employ
condensation of acetobromoglucose with cholest-5-en-3beta-ol on a copolymer of maleic
acid. N-substituted polyacrylamides can be synthesized by the reaction of activated polymers
with omega-aminoalkylglycosides: (1) (carbohydrate-spacer)(n)-polyacrylamide,
pseudopolysaccharides'; (2) (carbohydrate spacer)(n)-phosphatidylethanolamine(m)-
polyacrylamide, neoglycolipids, derivatives of phosphatidylethanolamine; (3) (carbohydrate-
spacer)(n)-biotin(m)-polyacrylamide. These biotinylated derivatives may attach to lectins on
the mucosal surface to facilitate absorption of the biologically active agent(s), e.g., a
polymer-encapsulated Y2 receptor-binding peptide.
Within more detailed aspects of the invention, one or more Y2 receptor-binding
peptide, analogs and mimetics, and/or other biologically active agents, disclosed herein,
optionally including secondary active agents such as protease inhibitor(s), cytokine(s),
additional modulator(s) of intercellular junctional physiology, etc., are modified and bound to
a polymeric carrier or matrix. For example, this may be accomplished by chemically binding
a peptide or protein active agent and other optional agent(s) within a crosslinked polymer
network. It is also possible to chemically modify the polymer separately with an interactive
agent such as a glycosidal containing molecule. In certain aspects, the biologically active
agent(s), and optional secondary active agent(s), may be functionalized, i.e., wherein an
appropriate reactive group is identified or is chemically added to the active agent(s). Most
often an ethylenic polymerizable group is added, and the functionalized active agent is then
copolymerized with monomers and a crosslinking agent using a standard polymerization
method such as solution polymerization (usually in water), emulsion, suspension or
dispersion polymerization. Often, the functionalizing agent is provided with a high enough
concentration of functional or polymerizable groups to insure that several sites on the active
agent(s) are functionalized. For example, in a polypeptide comprising 16 amine sites, it is
generally desired to functionalize at least 2, 4, 5, 7, and up to 8 or more of the sites.
After functionalization, the functionalized active agent(s) is/are mixed with monomers
and a crosslinking agent that comprise the reagents from which the polymer of interest is
formed. Polymerization is then induced in this medium to create a polymer containing the
bound active agent(s). The polymer is then washed with water or other appropriate solvents
and otherwise purified to remove trace unreacted impurities and, if necessary, ground or
broken up by physical means such as by stirring, forcing it through a mesh, ultrasonication or
other suitable means to a desired particle size. The solvent, usually water, is then removed in
such a manner as to not denature or otherwise degrade the active agent(s). One desired
method is lyophilization (freeze drying) but other methods are available and may be used
(e.g., vacuum drying, air drying, spray drying, etc.).
To introduce polymerizable groups in peptides, proteins and other active agents
within the invention, it is possible to react available amino, hydroxyl, thiol and other reactive
groups with electrophiles containing unsaturated groups. For example, unsaturated
monomers containing N-hydroxy succinimidyl groups, active carbonates such as p-
nitrophenyl carbonate, trichlorophenyl carbonates, tresylate, oxycarbonylimidazoles, epoxide,
isocyanates and aldehyde, and unsaturated carboxymethyl azides and unsaturated
orthopyridyl-disulfide belong to this category of reagents. Illustrative examples of
unsaturated reagents are allyl glycidyl ether, allyl chloride, allylbromide, allyl iodide,
acryloyl chloride, allyl isocyanate, allylsulfonyl chloride, maleic anhydride, copolymers of
maleic anhydride and allyl ether, and the like.
All of the lysine active derivatives, except aldehyde, can generally react with other
amino acids such as imidazole groups of histidine and hydroxyl groups of tyrosine and the
thiol groups of cystine if the local environment enhances nucleophilicity of these groups.
Aldehyde containing functionalizing reagents are specific to lysine. These types of reactions
with available groups from lysines, cysteines, tyrosine have been extensively documented in
the literature and are known to those skilled in the art.
In the case of biologically active agents that contain amine groups, it is convenient to
react such groups with an acyloyl chloride, such as acryloyl chloride, and introduce the
polymerizable acrylic group onto the reacted agent. Then during preparation of the polymer,
such as during the crosslinking of the copolymer of acrylamide and acrylic acid, the
functionalized active agent, through the acrylic groups, is attached to the polymer and
becomes bound thereto.
In additional aspects of the invention, biologically active agents, including peptides,
proteins, nucleosides, and other molecules which are bioactive in vivo, are conjugation-
stabilized by covalently bonding one or more active agent(s) to a polymer incorporating as an
integral part thereof both a hydrophilic moiety, e.g., a linear polyalkylene glycol, a lipophilic
moiety (see, e.g., U.S. Patent No. 5,681,811). In one aspect, a biologically active agent is
covalently coupled with a polymer comprising (i) a linear polyalkylene glycol moiety and (ii)
a lipophilic moiety, wherein the active agent, linear polyalkylene glycol moiety, and the
lipophilic moiety are conformationally arranged in relation to one another such that the active
therapeutic agent has an enhanced in vivo resistance to enzymatic degradation (i.e., relative to
its stability under similar conditions in an unconjugated form devoid of the polymer coupled
thereto). In another aspect, the conjugation-stabilized formulation has a three-dimensional
conformation comprising the biologically active agent covalently coupled with a polysorbate
complex comprising (i) a linear polyalkylene glycol moiety and (ii) a lipophilic moiety,
wherein the active agent, the linear polyalkylene glycol moiety and the lipophilic moiety are
conformationally arranged in relation to one another such that (a) the lipophilic moiety is
exteriorly available in the three-dimensional conformation, and (b) the active agent in the
composition has an enhanced in vivo resistance to enzymatic degradation.
In a further related aspect, a multiligand conjugated complex is provided which
comprises a biologically active agent covalently coupled with a triglyceride backbone moiety
through a polyalkylene glycol spacer group bonded at a carbon atom of the triglyceride
backbone moiety, and at least one fatty acid moiety covalently attached either directly to a
carbon atom of the triglyceride backbone moiety or covalently joined through a polyalkylene
glycol spacer moiety (see, e.g., U.S. Patent No. 5,681,811). In such a multiligand conjugated
therapeutic agent complex, the alpha' and beta carbon atoms of the triglyceride bioactive
moiety may have fatty acid moieties attached by covalently bonding either directly thereto, or
indirectly covalently bonded thereto through polyalkylene glycol spacer moieties.
Alternatively, a fatty acid moiety may be covalently attached either directly or through a
polyalkylene glycol spacer moiety to the alpha and alpha' carbons of the triglyceride
backbone moiety, with the bioactive therapeutic agent being covalently coupled with the
gamma-carbon of the triglyceride backbone moiety, either being directly covalently bonded
thereto or indirectly bonded thereto through a polyalkylene spacer moiety. It will be
recognized that a wide variety of structural, compositional, and conformational forms are
possible for the multiligand conjugated therapeutic agent complex comprising the triglyceride
backbone moiety, within the scope of the invention. It is further noted that in such a
multiligand conjugated therapeutic agent complex, the biologically active agent(s) may
advantageously be covalently coupled with the triglyceride modified backbone moiety
through alkyl spacer groups, or alternatively other acceptable spacer groups, within the scope
of the invention. As used in such context, acceptability of the spacer group refers to steric,
compositional, and end use application specific acceptability characteristics.
In yet additional aspects of the invention, a conjugation-stabilized complex is
provided which comprises a polysorbate complex comprising a polysorbate moiety including
a triglyceride backbone having covalently coupled to alpha, alpha' and beta carbon atoms
thereof functionalizing groups including (i) a fatty acid group; and (ii) a polyethylene glycol
group having a biologically active agent or moiety covalently bonded thereto, e.g., bonded to
an appropriate functionality of the polyethylene glycol group. Such covalent bonding may be
either direct, e.g., to a hydroxy terminal functionality of the polyethylene glycol group, or
alternatively, the covalent bonding may be indirect, e.g., by reactively capping the hydroxy
terminus of the polyethylene glycol group with a terminal carboxy functionality spacer group,
so that the resulting capped polyethylene glycol group has a terminal carboxy functionality to
which the biologically active agent or moiety may be covalently bonded.
In yet additional aspects of the invention, a stable, aqueously soluble, conjugation-
stabilized complex is provided which comprises one or more Y2 receptor-binding peptide
proteins, analogs and mimetics, and/or other biologically active agent(s)+ disclosed herein
covalently coupled to a physiologically compatible polyethylene glycol (PEG) modified
glycolipid moiety. In such complex, the biologically active agent(s) may be covalently
coupled to the physiologically compatible PEG modified glycolipid moiety by a labile
covalent bond at a free amino acid group of the active agent, wherein the labile covalent bond
is scissionable in vivo by biochemical hydrolysis and/or proteolysis. The physiologically
compatible PEG modified glycolipid moiety may advantageously comprise a polysorbate
polymer, e.g., a polysorbate polymer comprising fatty acid ester groups selected from the
group consisting of monopalmitate, dipalmitate, monolaurate, dilaurate, trilaurate, monoleate,
dioleate, trioleate, monostearate, distearate, and tristearate. In such complex, the
physiologically compatible PEG modified glycolipid moiety may suitably comprise a
polymer selected from the group consisting of polyethylene glycol ethers of fatty acids, and
polyethylene glycol esters of fatty acids, wherein the fatty acids for example comprise a fatty
acid selected from the group consisting of lauric, palmitic, oleic, and stearic acids.
Storage of Material
In certain aspects of the invention, the combinatorial formulations and/or coordinate
administration methods herein incorporate an effective amount of peptides and proteins
which may adhere to charged glass thereby reducing the effective concentration in the
container. Silanized containers, for example, silanized glass containers, are used to store the
finished product to reduce adsorption of the polypeptide or protein to a glass container.
In yet additional aspects of the invention, a kit for treatment of a mammalian subject
comprises a stable pharmaceutical composition of one or more Y2 receptor-binding peptide
compound(s) formulated for mucosal delivery to the mammalian subject wherein the
composition is effective to alleviate one or more symptom(s) of obesity, cancer, or
malnutrition or wasting related to cancer in said subject without unacceptable adverse side
effects. The kit further comprises a pharmaceutical reagent vial to contain the one or more
Y2 receptor-binding peptide compounds. The pharmaceutical reagent vial is composed of
pharmaceutical grade polymer, glass or other suitable material. The pharmaceutical reagent
vial is, for example, a silanized glass vial. The kit further comprises an aperture for delivery
of the composition to a nasal mucosal surface of the subject. The delivery aperture is
composed of a pharmaceutical grade polymer, glass or other suitable material. The delivery
aperture is, for example, a silanized glass.
A silanization technique combines a special cleaning technique for the surfaces to be
silanized with a silanization process at low pressure. The silane is in the gas phase and at an
enhanced temperature of the surfaces to be silanized. The method provides reproducible
surfaces with stable, homogeneous and functional silane layers having characteristics of a
monolayer. The silanized surfaces prevent binding to the glass of polypeptides or mucosal
delivery enhancing agents of the present invention. .
The procedure is useful to prepare silanized pharmaceutical reagent vials to hold Y2
receptor-binding peptide compositions of the present invention. Glass trays are cleaned by
rinsing with double distilled water (ddH2O) before using. The silane tray is then be rinsed
with 95% EtOH, and the acetone tray is rinsed with acetone. Pharmaceutical reagent vials
are sonicated in acetone for 10 minutes. After the acetone sonication, reagent vials are
washed in ddH2O tray at least twice. Reagent vials are sonicated in 0.1 M NaOH for 10
minutes. While the reagent vials are sonicating in NaOH, the silane solution is made under a
hood. (Silane solution: 800 mL of 95% ethanol; 96 L of glacial acetic acid; 25 mL of
glycidoxypropyltrimethoxy silane). After the NaOH sonication, reagent vials are washed in
ddH2O tray at least twice. The reagent vials are sonicated in silane solution for 3 to 5
minutes. The reagent vials are washed in 100% EtOH tray. The reagent vials are dried with
prepurified N2 gas and stored in a 100°C oven for at least 2 hours before using.
Bioadhesive Delivery Vehicles and Methods
In certain aspects of the invention, the combinatorial formulations and/or coordinate
administration methods herein incorporate an effective amount of a nontoxic bioadhesive as
an adjunct compound or carrier to enhance mucosal delivery of one or more biologically
active agent(s). Bioadhesive agents in this context exhibit general or specific adhesion to one
or more components or surfaces of the targeted mucosa. The bioadhesive maintains a desired
concentration gradient of the biologically active agent into or across the mucosa to ensure
penetration of even large molecules (e.g., peptides and proteins) into or through the mucosal
epithelium. Typically, employment of a bioadhesive within the methods and compositions of
the invention yields a two- to five- fold, often a five- to ten-fold increase in permeability for
peptides and proteins into or through the mucosal epithelium. This enhancement of epithelial
permeation often permits effective transmucosal delivery of large macromolecules, for
example to the basal portion of the nasal epithelium or into the adjacent extracellular
compartments or a blood plasma or CNS tissue or fluid.
This enhanced delivery provides for greatly improved effectiveness of delivery of
bioactive peptides, proteins and other macromolecular therapeutic species. These results will
depend in part on the hydrophilicity of the compound, whereby greater penetration will be
achieved with hydrophilic species compared to water insoluble compounds. In addition to
these effects, employment of bioadhesives to enhance drug persistence at the mucosal surface
can elicit a reservoir mechanism for protracted drug delivery, whereby compounds not only
penetrate across the mucosal tissue but also back-diffuse toward the mucosal surface once the
material at the surface is depleted.
A variety of suitable bioadhesives are disclosed in the art for oral administration, U.S.
Patent No.s 3,972,995; 4,259,314; 4,680,323; 4,740,365; 4,573,996; 4,292,299; 4,715,369;
4,876,092; 4,855,142; 4,250,163; 4,226,848; 4,948,580; U.S. Patent Reissue 33,093, which
find use within the novel methods and compositions of the invention. The potential of
various bioadhesive polymers as a mucosal, e.g., nasal, delivery platform within the methods
and compositions of the invention can be readily assessed by determining their ability to
retain and release Y2 receptor-binding peptide, as well as by their capacity to interact with
the mucosal surfaces following incorporation of the active agent therein. In addition, well
known methods will be applied to determine the biocompatibility of selected polymers with
the tissue at the site of mucosal administration. When the target mucosa is covered by mucus
(i.e., in the absence of mucolytic or mucus-clearing treatment), it can serve as a connecting
link to the underlying mucosal epithelium. Therefore, the term "bioadhesive" as used herein
also covers mucoadhesive compounds useful for enhancing mucosal delivery of biologically
active agents within the invention. However, adhesive contact to mucosal tissue mediated
through adhesion to a mucus gel layer may be limited by incomplete or transient attachment
between the mucus layer and the underlying tissue, particularly at nasal surfaces where rapid
mucus clearance occurs. In this regard, mucin glycoproteins are continuously secreted and,
immediately after their release from cells or glands, form a viscoelastic gel. The luminal
surface of the adherent gel layer, however, is continuously eroded by mechanical, enzymatic
and/or ciliary action. Where such activities are more prominent or where longer adhesion
times are desired, the coordinate administration methods and combinatorial formulation
methods of the invention may further incorporate mucolytic and/or ciliostatic methods or
agents as disclosed herein above.
Typically, mucoadhesive polymers for use within the invention are natural or
synthetic macromolecules which adhere to wet mucosal tissue surfaces by complex, but non-
specific, mechanisms. In addition to these mucoadhesive polymers, the invention also
provides methods and compositions incorporating bioadhesives that adhere directly to a cell
surface, rather than to mucus, by means of specific, including receptor-mediated, interactions.
One example of bioadhesives that function in this specific manner is the group of compounds
known as lectins. These are glycoproteins with an ability to specifically recognize and bind
to sugar molecules, e.g. glycoproteins or glycolipids, which form part of intranasal epithelial
cell membranes and can be considered as "lectin receptors".
In certain aspects of the invention, bioadhesive materials for enhancing intranasal
delivery of biologically active agents comprise a matrix of a hydrophilic, e.g., water soluble
or swellable, polymer or a mixture of polymers that can adhere to a wet mucous surface.
These adhesives may be formulated as ointments, hydrogels (see above) thin films, and other
application forms. Often, these adhesives have the biologically active agent mixed therewith
to effectuate slow release or local delivery of the active agent. Some are formulated with
additional ingredients to facilitate penetration of the active agent through the nasal mucosa,
e.g., into the circulatory system of the individual.
Various polymers, both natural and synthetic ones, show significant binding to mucus
and/or mucosal epithelial surfaces under physiological conditions. The strength of this
interaction can readily be measured by mechanical peel or shear tests. When applied to a
humid mucosal surface, many dry materials will spontaneously adhere, at least slightly. After
such an initial contact, some hydrophilic materials start to attract water by adsorption,
swelling or capillary forces, and if this water is absorbed from the underlying substrate or
from the polymer-tissue interface, the adhesion may be sufficient to achieve the goal of
enhancing mucosal absorption of biologically active agents. Such 'adhesion by hydration'
can be quite strong, but formulations adapted to employ this mechanism must account for
swelling which continues as the dosage transforms into a hydrated mucilage. This is
projected for many hydrocolloids useful within the invention, especially some cellulose-
derivatives, which are generally non-adhesive when applied in pre-hydrated state.
Nevertheless, bioadhesive drug delivery systems for mucosal administration are effective
within the invention when such materials are applied in the form of a dry polymeric powder,
microsphere, or film-type delivery form.
Other polymers adhere to mucosal surfaces not only when applied in dry, but also in
fully hydrated state, and in the presence of excess amounts of water. The selection of a
mucoadhesive thus requires due consideration of the conditions, physiological as well as
physico-chemical, under which the contact to the tissue will be formed and maintained. In
particular, the amount of water or humidity usually present at the intended site of adhesion,
and the prevailing pH, are known to largely affect the mucoadhesive binding strength of
different polymers.
Several polymeric bioadhesive drug delivery systems have been fabricated and
studied in the past 20 years, not always with success. A variety of such carriers are, however,
currently used in clinical applications involving dental, orthopedic, ophthalmological, and
surgical uses. For example, acrylic-based hydrogels have been used extensively for
bioadhesive devices. Acrylic-based hydrogels are well suited for bioadhesion due to their
flexibility and nonabrasive characteristics in the partially swollen state, which reduce
damage-causing attrition to the tissues in contact. Furthermore, their high permeability in the
swollen state allows unreacted monomer, un-crosslinked polymer chains, and the initiator to
be washed out of the matrix after polymerization, which is an important feature for selection
of bioadhesive materials for use within the invention. Acrylic-based polymer devices exhibit
very high adhesive bond strength. For controlled mucosal delivery of peptide and protein
drugs, the methods and compositions of the invention optionally include the use of carriers,
e.g., polymeric delivery vehicles, that function in part to shield the biologically active agent
from proteolytic breakdown, while at the same time providing for enhanced penetration of the
peptide or protein into or through the nasal mucosa. In this context, bioadhesive polymers
have demonstrated considerable potential for enhancing oral drug delivery. As an example,
the bioavailability of 9-desglycinamide, 8-arGlnine vasopressin (DGAVP) intraduodenally
administered to rats together with a 1% (w/v) saline dispersion of the mucoadhesive
poly(acrylic acid) derivative polycarbophil, was 3-5-fold increased compared to an aqueous
solution of the peptide drug without this polymer.
Mucoadhesive polymers of the poly(acrylic acid)-type are potent inhibitors of some
intestinal proteases. The mechanism of enzyme inhibition is explained by the strong affinity
of this class of polymers for divalent cations, such as calcium or zinc, which are essential
cofactors of metallo-proteinases, such as trypsin and chymotrypsin. Depriving the proteases
of their cofactors by poly(acrylic acid) was reported to induce irreversible structural changes
of the enzyme proteins which were accompanied by a loss of enzyme activity. At the same
time, other mucoadhesive polymers (e.g., some cellulose derivatives and chitosan) may not
inhibit proteolytic enzymes under certain conditions. In contrast to other enzyme inhibitors
contemplated for use within the invention (e.g. aprotinin, bestatin), which are relatively small
molecules, the trans-nasal absorption of inhibitory polymers is likely to be minimal in light of
the size of these molecules, and thereby eliminate possible adverse side effects. Thus,
mucoadhesive polymers, particularly of the poly(acrylic acid)-type, may serve both as an
absorption-promoting adhesive and enzyme-protective agent to enhance controlled delivery
of peptide and protein drugs, especially when safety concerns are considered.
In addition to protecting against enzymatic degradation, bioadhesives and other
polymeric or non-polymeric absorption-promoting agents for use within the invention may
directly increase mucosal permeability to biologically active agents. To facilitate the
transport of large and hydrophilic molecules, such as peptides and proteins, across the nasal
epithelial barrier, mucoadhesive polymers and other agents have been postulated to yield
enhanced permeation effects beyond what is accounted for by prolonged premucosal
residence time of the delivery system. The time course of drug plasma concentrations
reportedly suggested that the bioadhesive microspheres caused an acute, but transient
increase of insulin permeability across the nasal mucosa. Other mucoadhesive polymers for
use within the invention, for example chitosan, reportedly enhance the permeability of certain
mucosal epithelia even when they are applied as an aqueous solution or gel. Another
mucoadhesive polymer reported to directly affect epithelial permeability is hyaluronic acid
and ester derivatives thereof. A particularly useful bioadhesive agent within the coordinate
administration, and/or combinatorial formulation methods and compositions of the invention
is chitosan, as well as its analogs and derivatives. Chitosan is a non-toxic, biocompatible and
biodegradable polymer that is widely used for pharmaceutical and medical applications
because of its favorable properties of low toxicity and good biocompatibility. It is a natural
polyaminosaccharide prepared from chitin by N-deacetylation with alkali. As used within the
methods and compositions of the invention, chitosan increases the retention of Y2 receptor-
binding peptide proteins, analogs and mimetics, and other biologically active agents disclosed
herein at a mucosal site of application. This mode of administration can also improve patient
compliance and acceptance. As further provided herein, the methods and compositions of the
invention will optionally include a novel chitosan derivative or chemically modified form of
chitosan. One such novel derivative for use within the invention is denoted as a P-[l?4]-2-
guanidino-2-deoxy-D-glucose polymer (poly-GuD). Chitosan is the N-deacetylated product
of chitin, a naturally occurring polymer that has been used extensively to prepare
microspheres for oral and intra-nasal formulations. The chitosan polymer has also been
proposed as a soluble carrier for parenteral drug delivery. Within one aspect of the invention,
o-methylisourea is used to convert a chitosan amine to its guanidinium moiety. The
guanidinium compound is prepared, for example, by the reaction between equi-normal
solutions of chitosan and o-methylisourea at pH above 8.0.
The guanidinium product is -[ 14]-guanidino-2-deoxy-D-glucose polymer. It is
abbreviated as Poly-GuD in this context (Monomer F.W. of Amine in Chitosan = 161;
Monomer F.W. of Guanidinium in Poly-GuD = 203).
One exemplary Poly-GuD preparation method for use within the invention involves
the following protocol.
Solutions:
Preparation of 0.5% Acetic Acid Solution (0.088N):
Pipette 2.5 mL glacial acetic acid into a 500 mL volumetric flask, dilute to
volume with purified water.
Preparation of 2N NaOH Solution:
Transfer about 20 g NaOH pellets into a beaker with about 150 mL of purified
water. Dissolve and cool to room temperature. Transfer the solution into a 250-mL
volumetric flask, dilute to volume with purified water.
Preparation of O-methylisourea Sulfate (0.4N urea group equivalent):
Transfer about 493 mg of O-methylisourea sulfate into a 10-mL volumetric
flask, dissolve and dilute to volume with purified water.
The pH of the solution is 4.2
Preparation of Barium Chloride Solution (0.2M):
Transfer about 2.086 g of Barium chloride into a 50-mL volumetric flask,
dissolve and dilute to volume with purified water.
Preparation of Chitosan Solution (0.06N amine equivalent):
Transfer about 100 mg Chitosan into a 50 mL beaker, add 10 mL 0.5% Acetic
Acid (0.088 N). Stir to dissolve completely.
The pH of the solution is about 4.5
Preparation of O-methylisourea Chloride Solution (0.2N urea group
equivalent):
Pipette 5.0 mL of O-methylisourea sulfate solution (0.4 N urea group
equivalent) and 5 mL of 0.2M Barium chloride solution into a beaker. A precipitate is
formed. Continue to mix the solution for additional 5 minutes. Filter the solution through
0.45m filter and discard the precipitate. The concentration of O-methylisourea chloride in the
supernatant solution is 0.2 N urea group equivalents.
The pH of the solution is 4.2.
Procedure:
Add 1.5 mL of 2 N NaOH to 10 mL of the chitosan solution (0.06N amine
equivalent) prepared as described in Section 2.5. Adjust the pH of the solution with 2N
NaOH to about 8.2 to 8.4. Stir the solution for additional 10 minutes. Add 3.0 mL O-
methylisourea chloride solution (0.2N urea group equivalent) prepared as described above.
Stir the solution overnight.
Adjust the pH of solution to 5.5 with 0.5% Acetic Acid (0.088N).
Dilute the solution to a final volume of 25 mL using purified water.
The Poly-GuD concentration in the solution is 5 mg/mL, equivalent to 0.025 N
(guanidium group).
Additional compounds classified as bioadhesive agents for use within the present
invention act by mediating specific interactions, typically classified as "receptor-ligand
interactions" between complementary structures of the bioadhesive compound and a
component of the mucosal epithelial surface. Many natural examples illustrate this form of
specific binding bioadhesion, as exemplified by lectin-sugar interactions. Lectins are (glyco)
proteins of non-immune oriGln which bind to polysaccharides or glycoconjugates.
Several plant lectins have been investigated as possible pharmaceutical absorption-
promoting agents. One plant lectin, Phaseolus vulgaris hemagglutinin (PHA), exhibits high
oral bioavailability of more than 10% after feeding to rats. Tomato {Lycopersicon
esculeutum) lectin (TL) appears safe for various modes of administration.
In summary, the foregoing bioadhesive agents are useful in the combinatorial
formulations and coordinate administration methods of the instant invention, which
optionally incorporate an effective amount and form of a bioadhesive agent to prolong
persistence or otherwise increase mucosal absorption of one or more Y2 receptor-binding
peptide proteins, analogs and mimetics, and other biologically active agents. The
bioadhesive agents may be coordinately administered as adjunct compounds or as additives
within the combinatorial formulations of the invention. In certain embodiments, the
bioadhesive agent acts as a 'pharmaceutical glue', whereas in other embodiments adjunct
delivery or combinatorial formulation of the bioadhesive agent serves to intensify contact of
the biologically active agent with the nasal mucosa, in some cases by promoting specific
receptor-ligand interactions with epithelial cell "receptors", and in others by increasing
epithelial permeability to significantly increase the drug concentration gradient measured at a
target site of delivery (e.g., liver, blood plasma, or CNS tissue or fluid). Yet additional
bioadhesive agents for use within the invention act as enzyme (e.g., protease) inhibitors to
enhance the stability of mucosally administered biotherapeutic agents delivered coordinately
or in a combinatorial formulation with the bioadhesive agent.
Liposomes and Micellar Delivery Vehicles
The coordinate administration methods and combinatorial formulations of the instant
invention optionally incorporate effective lipid or fatty acid based carriers, processing agents,
or delivery vehicles, to provide improved formulations for mucosal delivery of Y2 receptor-
binding peptide proteins, analogs and mimetics, and other biologically active agents. For
example, a variety of formulations and methods are provided for mucosal delivery which
comprise one or more of these active agents, such as a peptide or protein, admixed or
encapsulated by, or coordinately administered with, a liposome, mixed micellar carrier, or
emulsion, to enhance chemical and physical stability and increase the half life of the
biologically active agents (e.g., by reducing susceptibility to proteolysis, chemical
modification and/or denaturation) upon mucosal delivery.
Within certain aspects of the invention, specialized delivery systems for biologically
active agents comprise small lipid vesicles known as liposomes. These are typically made
from natural, biodegradable, non-toxic, and non-immunogenic lipid molecules, and can
efficiently entrap or bind drug molecules, including peptides and proteins, into, or onto, their
membranes. The attractiveness of liposomes as a peptide and protein delivery system within
the invention is increased by the fact that the encapsulated proteins can remain in their
preferred aqueous environment within the vesicles, while the liposomal membrane protects
them against proteolysis and other destabilizing factors. Even though not all liposome
preparation methods known are feasible in the encapsulation of peptides and proteins due to
their unique physical and chemical properties, several methods allow the encapsulation of
these macromolecules without substantial deactivation.
A variety of methods are available for preparing liposomes for use within the
invention, U.S. Patent Nos. 4,235,871, 4,501,728, and 4,837,028. For use with liposome
delivery, the biologically active agent is typically entrapped within the liposome, or lipid
vesicle, or is bound to the outside of the vesicle.
Like liposomes, unsaturated long chain fatty acids, which also have enhancing
activity for mucosal absorption, can form closed vesicles with bilayer-like structures (so
called "ufasomes"). These can be formed, for example, using oleic acid to entrap
biologically active peptides and proteins for mucosal, e.g., intranasal, delivery within the
invention.
Other delivery systems for use within the invention combine the use of polymers and
liposomes to ally the advantageous properties of both vehicles such as encapsulation inside
the natural polymer fibrin. In addition, release of biotherapeutic compounds from this
delivery system is controllable through the use of covalent crosslinking and the addition of
antifibrinolytic agents to the fibrin polymer.
More simplified delivery systems for use within the invention include the use of
cationic lipids as delivery vehicles or carriers, which can be effectively employed to provide
an electrostatic interaction between the lipid carrier and such charged biologically active
agents as proteins and polyanionic nucleic acids. This allows efficient packaGlng of the drugs
into a form suitable for mucosal administration and/or subsequent delivery to systemic
compartments.
Additional delivery vehicles for use within the invention include long and medium
chain fatty acids, as well as surfactant mixed micelles with fatty acids. Most naturally
occurring lipids in the form of esters have important implications with regard to their own
transport across mucosal surfaces. Free fatty acids and their monoglycerides which have
polar groups attached have been demonstrated in the form of mixed micelles to act on the
intestinal barrier as penetration enhancers. This discovery of barrier modifying function of
free fatty acids (carboxylic acids with a chain length varying from 12 to 20 carbon atoms) and
their polar derivatives has stimulated extensive research on the application of these agents as
mucosal absorption enhancers.
For use within the methods of the invention, long chain fatty acids, especially
fusogenic lipids (unsaturated fatty acids and monoglycerides such as oleic acid, linoleic acid,
linoleic acid, monoolein, etc.) provide useful carriers to enhance mucosal delivery of Y2
receptor-binding peptide, analogs and mimetics, and other biologically active agents
disclosed herein. Medium chain fatty acids (C6 to C12) and monoglycerides have also been
shown to have enhancing activity in intestinal drug absorption and can be adapted for use
within the mocosal delivery formulations and methods of the invention. In addition, sodium
salts of medium and long chain fatty acids are effective delivery vehicles and absorption-
enhancing agents for mucosal delivery of biologically active agents within the invention.
Thus, fatty acids can be employed in soluble forms of sodium salts or by the addition of non-
toxic surfactants, e.g., polyoxyethylated hydrogenated castor oil, sodium taurocholate, etc.
Other fatty acid and mixed micellar preparations that are useful within the invention include,
but are not limited to, Na caprylate (C8), Na caprate (C10), Na laurate (C12) or Na oleate
(C18), optionally combined with bile salts, such as glycocholate and taurocholate.
Pegylation
Additional methods and compositions provided within the invention involve chemical
modification of biologically active peptides and proteins by covalent attachment of polymeric
materials, for example dextrans, polyvinyl pyrrolidones, glycopeptides, polyethylene glycol
and polyamino acids. The resulting conjugated peptides and proteins retain their biological
activities and solubility for mucosal administration. In alternate embodiments, Y2 receptor-
binding peptide proteins, analogs and mimetics, and other biologically active peptides and
proteins, are conjugated to polyalkylene oxide polymers, particularly polyethylene glycols
(PEG). U.S. Patent No. 4,179,337.
Amine-reactive PEG polymers for use within the invention include SC-PEG with
molecular masses of 2000, 5000, 10000, 12000, and 20 000; U-PEG-10000; NHS-PEG-3400-
biotin; T-PEG-5000; T-PEG-12000; and TPC-PEG-5000. PEGylation of biologically active
peptides and proteins may be achieved by modification of carboxyl sites (e.g., aspartic acid or
glutamic acid groups in addition to the carboxyl terminus). The utility of PEG-hydrazide in
selective modification of carbodiimide-activated protein carboxyl groups under acidic
conditions has been described. Alternatively, bifunctional PEG modification of biologically
active peptides and proteins can be employed. In some procedures, charged amino acid
residues, including lysine, aspartic acid, and glutamic acid, have a marked tendency to be
solvent accessible on protein surfaces.
Other Stabilizing Modifications of Active Agents
In addition to PEGylation, biologically active agents such as peptides and proteins for
use within the invention can be modified to enhance circulating half-life by shielding the
active agent via conjugation to other known protecting or stabilizing compounds, for example
by the creation of fusion proteins with an active peptide, protein, analog or mimetic linked to
one or more carrier proteins, such as one or more immunoglobulin chains.
Formulation and Administration
Mucosal delivery formulations of the present invention comprise Y2 receptor-binding
peptide, analogs and mimetics, typically combined together with one or more
pharmaceutically acceptable carriers and, optionally, other therapeutic ingredients. The
carrier(s) must be "pharmaceutically acceptable" in the sense of being compatible with the
other ingredients of the formulation and not eliciting an unacceptable deleterious effect in the
subject. Such carriers are described herein above or are otherwise well known to those
skilled in the art of pharmacology. Desirably, the formulation should not include substances
such as enzymes or oxidizing agents with which the biologically active agent to be
administered is known to be incompatible. The formulations may be prepared by any of the
methods well known in the art of pharmacy.
Within the compositions and methods of the invention, the Y2 receptor-binding
peptide proteins, analogs and mimetics, and other biologically active agents disclosed herein
may be administered to subjects by a variety of mucosal administration modes, including by
oral, rectal, vaGlnal, intranasal, intrapulmonary, or transdermal delivery, or by topical
delivery to the eyes, ears, skin or other mucosal surfaces. Optionally, Y2 receptor-binding
peptide proteins, analogs and mimetics, and other biologically active agents disclosed herein
can be coordinately or adjunctively administered by non-mucosal routes, including by
intramuscular, subcutaneous, intravenous, intra-atrial, intra-articular, intraperitoneal, or
parenteral routes. In other alternative embodiments, the biologically active agent(s) can be
administered ex vivo by direct exposure to cells, tissues or organs oriGlnating from a
mammalian subject, for example as a component of an ex vivo tissue or organ treatment
formulation that contains the biologically active agent in a suitable, liquid or solid carrier.
Compositions according to the present invention are often administered in an aqueous
solution as a nasal or pulmonary spray and may be dispensed in spray form by a variety of
methods known to those skilled in the art. Preferred systems for dispensing liquids as a nasal
spray are disclosed in U.S. Patent No. 4,511,069. The formulations may be presented in
multi-dose containers, for example in the sealed dispensing system disclosed in U.S. Patent
No. 4,511,069. Additional aerosol delivery forms may include, e.g., compressed air-, jet-,
ultrasonic-, and piezoelectric nebulizers, which deliver the biologically active agent dissolved
or suspended in a pharmaceutical solvent, e.g., water, ethanol, or a mixture thereof.
Nasal and pulmonary spray solutions of the present invention typically comprise the
drug or drug to be delivered, optionally formulated with a surface-active agent, such as a
nonionic surfactant (e.g., polysorbate-80), and one or more buffers. In some embodiments of
the present invention, the nasal spray solution further comprises a propellant. The pH of the
nasal spray solution is optionally between about pH 3.0 and 6.0, preferably 5.0±0.3. Suitable
buffers for use within these compositions are as described above or as otherwise known in the
art. Other components may be added to enhance or maintain chemical stability, including
preservatives, surfactants, dispersants, or gases. Suitable preservatives include, but are not
limited to, phenol, methyl paraben, paraben, m-cresol, thiomersal, chlorobutanol,
benzylalkonimum chloride, and the like. Suitable surfactants include, but are not limited to,
oleic acid, sorbitan trioleate, polysorbates, lecithin, phosphotidyl cholines, and various long
chain diglycerides and phospholipids. Suitable dispersants include, but are not limited to,
ethylenediaminetetraacetic acid, and the like. Suitable gases include, but are not limited to,
nitrogen, helium, chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs), carbon dioxide,
air, and the like.
Within alternate embodiments, mucosal formulations are administered as dry powder
formulations comprising the biologically active agent in a dry, usually lyophilized, form of an
appropriate particle size, or within an appropriate particle size range, for intranasal delivery.
Minimum particle size appropriate for deposition within the nasal or pulmonary passages is
often about 0.5 m mass median equivalent aerodynamic diameter (MMEAD), commonly
about 1 u MMEAD, and more typically about 2 m MMEAD. Maximum particle size
appropriate for deposition within the nasal passages is often about 10 m MMEAD, commonly
about 8 m MMEAD, and more typically about 4m MMEAD. Intranasally respirable powders
within these size ranges can be produced by a variety of conventional techniques, such as jet
milling, spray drying, solvent precipitation, supercritical fluid condensation, and the like.
These dry powders of appropriate MMEAD can be administered to a patient via a
conventional dry powder inhaler (DPI), which rely on the patient's breath, upon pulmonary or
nasal inhalation, to disperse the power into an aerosolized amount. Alternatively, the dry
powder may be administered via air-assisted devices that use an external power source to
disperse the powder into an aerosolized amount, e.g., a piston pump.
Dry powder devices typically require a powder mass in the range from about 1 mg to
20 mg to produce a single aerosolized dose ("puff). If the required or desired dose of the
biologically active agent is lower than this amount, the powdered active agent will typically
be combined with a pharmaceutical dry bulking powder to provide the required total powder
mass. Preferred dry bulking powders include sucrose, lactose, dextrose, mannitol, glycine,
trehalose, human serum albumin (HSA), and starch. Other suitable dry bulking powders
include cellobiose, dextrans, maltotriose, pectin, sodium citrate, sodium ascorbate, and the
like.
To formulate compositions for mucosal delivery within the present invention, the
biologically active agent can be combined with various pharmaceutically acceptable
additives, as well as a base or carrier for dispersion of the active agent(s). Desired additives
include, but are not limited to, pH control agents, such as arGlnine, sodium hydroxide,
glycine, hydrochloric acid, citric acid, etc. In addition, local anesthetics (e.g., benzyl
alcohol), isotonizing agents (e.g., sodium chloride, mannitol, sorbitol), adsorption inhibitors
(e.g., Tween 80), solubility enhancing agents (e.g., cyclodextrins and derivatives thereof),
stabilizers (e.g., serum albumin), and reducing agents (e.g., glutathione) can be included.
When the composition for mucosal delivery is a liquid, the tonicity of the formulation, as
measured with reference to the tonicity of 0.9% (w/v) physiological saline solution taken as
unity, is typically adjusted to a value at which no substantial, irreversible tissue damage will
be induced in the nasal mucosa at the site of administration. Generally, the tonicity of the
solution is adjusted to a value of about 1/3 to 3, more typically 1/2 to 2, and most often 3/4 to
1.7.
The biologically active agent may be dispersed in a base or vehicle, which may
comprise a hydrophilic compound having a capacity to disperse the active agent and any
desired additives. The base may be selected from a wide range of suitable carriers, including
but not limited to, copolymers of polycarboxylic acids or salts thereof, carboxylic anhydrides
(e.g. maleic anhydride) with other monomers (e.g. methyl (meth)acrylate, acrylic acid, etc.),
hydrophilic vinyl polymers such as polyvinyl acetate, polyvinyl alcohol,
polyvinylpyrrolidone, cellulose derivatives such as hydroxymethylcellulose,
hydroxypropylcellulose, etc., and natural polymers such as chitosan, collagen, sodium
alGlnate, gelatin, hyaluronic acid, and nontoxic metal salts thereof. Often, a biodegradable
polymer is selected as a base or carrier, for example, polylactic acid, poly(lactic acid-glycolic
acid) copolymer, polyhydroxybutyric acid, poly(hydroxybutyric acid-glycolic acid)
copolymer and mixtures thereof. Alternatively or additionally, synthetic fatty acid esters
such as polyglycerin fatty acid esters, sucrose fatty acid esters, etc. can be employed as
carriers. Hydrophilic polymers and other carriers can be used alone or in combination, and
enhanced structural integrity can be imparted to the carrier by partial crystallization, ionic
bonding, crosslinking and the like. The carrier can be provided in a variety of forms,
including, fluid or viscous solutions, gels, pastes, powders, microspheres and films for direct
application to the nasal mucosa. The use of a selected carrier in this context may result in
promotion of absorption of the biologically active agent.
The biologically active agent can be combined with the base or carrier according to a
variety of methods, and release of the active agent may be by diffusion, disintegration of the
carrier, or associated formulation of water channels. In some circumstances, the active agent
is dispersed in microcapsules (microspheres) or nanocapsules (nanospheres) prepared from a
suitable polymer, e.g., isobutyl 2-cyanoacrylate and dispersed in a biocompatible dispersing
medium applied to the nasal mucosa, which yields sustained delivery and biological activity
over a protracted time.
To further enhance mucosal delivery of pharmaceutical agents within the invention,
formulations comprising the active agent may also contain a hydrophilic low molecular
weight compound as a base or excipient. Such hydrophilic low molecular weight compounds
provide a passage medium through which a water-soluble active agent, such as a
physiologically active peptide or protein, may diffuse through the base to the body surface
where the active agent is absorbed. The hydrophilic low molecular weight compound
optionally absorbs moisture from the mucosa or the administration atmosphere and dissolves
the water-soluble active peptide. The molecular weight of the hydrophilic low molecular
weight compound is generally not more than 10000 and preferably not more than 3000.
Exemplary hydrophilic low molecular weight compound include polyol compounds, such as
oligo-, di- and monosaccarides such as sucrose, mannitol, sorbitol, lactose, L-arabinose, D-
erythrose, D-ribose, D-xylose, D-mannose, trehalose, D-galactose, lactulose, cellobiose,
gentibiose, glycerin and polyethylene glycol. Other examples of hydrophilic low molecular
weight compounds useful as carriers within the invention include N-methylpyrrolidone, and
alcohols (e.g. oligovinyl alcohol, ethanol, ethylene glycol, propylene glycol, etc.) These
hydrophilic low molecular weight compounds can be used alone or in combination with one
another or with other active or inactive components of the intranasal formulation.
The compositions of the invention may alternatively contain as pharmaceutically
acceptable carriers substances as required to approximate physiological conditions, such as
pH adjusting and buffering agents, tonicity adjusting agents, wetting agents and the like, for
example, sodium acetate, sodium lactate, sodium chloride, potassium chloride, calcium
chloride, sorbitan monolaurate, triethanolamine oleate, etc. For solid compositions,
conventional nontoxic pharmaceutically acceptable carriers can be used which include, for
example, pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium
saccharin, talcum, cellulose, glucose, sucrose, magnesium carbonate, and the like.
Therapeutic compositions for administering the biologically active agent can also be
formulated as a solution, microemulsion, or other ordered structure suitable for high
concentration of active ingredients. The carrier can be a solvent or dispersion medium
containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and
liquid polyethylene glycol, and the like), and suitable mixtures thereof. Proper fluidity for
solutions can be maintained, for example, by the use of a coating such as lecithin, by the
maintenance of a desired particle size in the case of dispersible formulations, and by the use
of surfactants. In many cases, it will be desirable to include isotonic agents, for example,
sugars, polyalcohols such as mannitol, sorbitol, or sodium chloride in the composition.
Prolonged absorption of the biologically active agent can be brought about by including in
the composition an agent which delays absorption, for example, monostearate salts and
gelatin.
In certain embodiments of the invention, the biologically active agent is administered
in a time-release formulation, for example in a composition which includes a slow release
polymer. The active agent can be prepared with carriers that will protect against rapid
release, for example a controlled release vehicle such as a polymer, microencapsulated
delivery system or bioadhesive gel. Prolonged delivery of the active agent, in various
compositions of the invention can be brought about by including in the composition agents
that delay absorption, for example, aluminum monosterate hydrogels and gelatin. When
controlled release formulations of the biologically active agent is desired, controlled release
binders suitable for use in accordance with the invention include any biocompatible
controlled-release material which is inert to the active agent and which is capable of
incorporating the biologically active agent. Numerous such materials are known in the art.
Useful controlled-release binders are materials that are metabolized slowly under
physiological conditions following their intranasal delivery (e.g., at the nasal mucosal
surface, or in the presence of bodily fluids following transmucosal delivery). Appropriate
binders include but are not limited to biocompatible polymers and copolymers previously
used in the art in sustained release formulations. Such biocompatible compounds are non-
toxic and inert to surrounding tissues, and do not trigger significant adverse side effects such
as nasal irritation, immune response, inflammation, or the like. They are metabolized into
metabolic products that are also biocompatible and easily eliminated from the body.
Exemplary polymeric materials for use in this context include, but are not limited to,
polymeric matrices derived from copolymeric and homopolymeric polyesters having
hydrolysable ester linkages. A number of these are known in the art to be biodegradable and
to lead to degradation products having no or low toxicity. Exemplary polymers include
polyglycolic acids (PGA) and polylactic acids (PLA), poly(DL-lactic acid-co-glycolic
acid)(DL PLGA), poly(D-lactic acid-coglycolic acid)(D PLGA) and poly(L-lactic acid-co-
glycolic acid)(L PLGA). Other useful biodegradable or bioerodable polymers include but are
not limited to such polymers as poly(epsilon-caprolactone), poly(epsilon-aprolactone-CO-
lactic acid), poly(s-aprolactone-CO-glycolic acid), poly(beta-hydroxy butyric acid),
poly(alkyl-2-cyanoacrilate), hydrogels such as poly(hydroxyethyl methacrylate), polyamides,
poly(amino acids) (i.e., L-leucine, glutamic acid, L-aspartic acid and the like), poly (ester
urea), poly (2-hydroxyethyl DL-aspartamide), polyacetal polymers, polyorthoesters,
polycarbonate, polymaleamides, polysaccharides and copolymers thereof. Many methods for
preparing such formulations are generally known to those skilled in the art. Other useful
formulations include controlled-release compositions e.g., microcapsules, U.S. Patent Nos.
4,652,441 and 4,917,893, lactic acid-glycolic acid copolymers useful in making
microcapsules and other formulations, U.S. Patent Nos. 4,677,191 and 4,728,721, and
sustained-release compositions for water-soluble peptides, U.S. Patent No. 4,675,189.
Sterile solutions can be prepared by incorporating the active compound in the required
amount in an appropriate solvent with one or a combination of ingredients enumerated above,
as required, followed by filtered sterilization. Generally, dispersions are prepared by
incorporating the active compound into a sterile vehicle that contains a basic dispersion
medium and the required other ingredients from those enumerated above. In the case of
sterile powders, methods of preparation include vacuum drying and freeze-drying which
yields a powder of the active ingredient plus any additional desired ingredient from a
previously sterile-filtered solution thereof. The prevention of the action of microorganisms
can be accomplished by various antibacterial and antifungal agents, for example, parabens,
chlorobutanol, phenol, sorbic acid, thimerosal, and the like.
Mucosal administration according to the invention allows effective self-administration
of treatment by patients, provided that sufficient safeguards are in place to control and
monitor dosing and side effects. Mucosal administration also overcomes certain drawbacks
of other administration forms, such as injections, that are painful and expose the patient to
possible infections and may present drug bioavailability problems. For nasal and pulmonary
delivery, systems for controlled aerosol dispensing of therapeutic liquids as a spray are well
known. In one embodiment, metered doses of active agent are delivered by means of a
specially constructed mechanical pump valve, U.S. Patent No. 4,511,069.
Dosage
For prophylactic and treatment purposes, the biologically active agent(s) disclosed
herein may be administered to the subject in a single bolus delivery, via continuous delivery
(e.g., continuous transdermal, mucosal, or intravenous delivery) over an extended time
period, or in a repeated administration protocol (e.g., by an hourly, daily or weekly, repeated
administration protocol). In this context, a therapeutically effective dosage of the
biologically active agent(s) may include repeated doses within a prolonged prophylaxis or
treatment regimen that will yield clinically significant results to alleviate one or more
symptoms or detectable conditions associated with a targeted disease or condition as set forth
above. Determination of effective dosages in this context is typically based on animal model
studies followed up by human clinical trials and is guided by determining effective dosages
and administration protocols that significantly reduce the occurrence or severity of targeted
disease symptoms or conditions in the subject. Suitable models in this regard include, for
example, murine, rat, porcine, feline, non-human primate, and other accepted animal model
subjects known in the art. Alternatively, effective dosages can be determined using in vitro
models (e.g., immunologic and histopathologic assays). Using such models, only ordinary
calculations and adjustments are typically required to determine an appropriate concentration
and dose to administer a therapeutically effective amount of the biologically active agent(s)
(e.g., amounts that are intranasally effective, transdermally effective, intravenously effective,
or intramuscularly effective to elicit a desired response).
The actual dosage of biologically active agents will of course vary according to
factors such as the disease indication and particular status of the subject (e.g., the subject's
age, size, fitness, extent of symptoms, susceptibility factors, etc), time and route of
administration, other drugs or treatments being administered concurrently, as well as the
specific pharmacology of the biologically active agent(s) for eliciting the desired activity or
biological response in the subject. Dosage regimens may be adjusted to provide an optimum
prophylactic or therapeutic response. A therapeutically effective amount is also one in which
any toxic or detrimental side effects of the biologically active agent are outweighed in clinical
terms by therapeutically beneficial effects. A non-limiting range for a therapeutically
effective amount of an Y2 agonist within the methods and formulations of the invention is
0.7µg/kg to about 25 µg/kg. To promote weight loss, an intranasal dose of Y2 receptor-
binding peptide is administered at dose high enough to promote satiety but low enough so as
not to induce any unwanted side-effects such as nausea. A preferred intranasal dose of PYY3.
36 is about 1 ug -10mg/kg weight of the patient, most preferably from about 1.5 µg/kg to
about 3 µg/kg weight of the patient. In a standard dose a patient will receive 50 µg to 1600
ug, more preferably about between 75 (ig to 800 ug, most preferably 100 µg, 150 µg, 200 µg
to about 400 µg. . Alternatively, a non-limiting range for a therapeutically effective amount
of a biologically active agent within the methods and formulations of the invention is
between about 0.001 pmol to about 100 pmol per kg body weight, between about 0.01 pmol
to about 10 pmol per kg body weight, between about 0.1 pmol to about 5 pmol per kg body
weight, or between about 0.5 pmol to about 1.0 pmol per kg body weight. Dosages within
this range can be achieved by single or multiple administrations, including, e.g., multiple
administrations per day, daily or weekly administrations. Per administration, it is desirable to
administer at least one microgram of the biologically active agent (e.g., one or more Y2
receptor-binding peptide proteins, analogs and mimetics, and other biologically active
agents), more typically between about 10mg and 5.0 mg, and in certain embodiments
between about 100 µg and 1.0 or 2.0 mg to an average human subject. For certain oral
applications, doses as high as 0.5 mg per kg body weight may be necessary to achieve
adequate plasma levels. It is to be further noted that for each particular subject, specific
dosage regimens should be evaluated and adjusted over time according to the individual need
and professional judgment of the person administering or supervising the administration of
the permeabilizing peptide(s) and other biologically active agent(s). An intranasal dose of a
PYY will range from 50 µg to 1600 ug of PYY, preferably 75 ug to 800 ug, more preferably
100 µg to 400 µg with a most preferred dose being between 100 µg to 200ug with 150 µg
being a dose that is considered to be highly effective. Repeated intranasal dosing with the
formulations of the invention, on a schedule ranGlng from about 0.1 to24 hours between
doses, preferably between 0.1 and 2.0 hours between doses, will maintain normalized,
sustained therapeutic levels of Y2 receptor-binding peptide to maximize clinical benefits
while minimizing the risks of excessive exposure and side effects. This dose can be
administered several times a day, preferably one half hour before a meal or when hunger
occurs to promote satiety.
Dosage of Y2 agonists such as PYY may be varied by the attending clinician or
patient, if self administering an over the counter dosage form, to maintain a desired
concentration at the target site.
In an alternative embodiment, the invention provides compositions and methods for
intranasal delivery of Y2 receptor-binding peptide, wherein the Y2 receptor-binding peptide
compound(s) is/are repeatedly administered through an intranasal effective dosage regimen
that involves multiple administrations of the Y2 receptor-binding peptide to the subject
during a daily or weekly schedule to maintain a therapeutically effective elevated and
lowered pulsatile level of Y2 receptor-binding peptide during an extended dosing period.
The compositions and method provide Y2 receptor-binding peptide compound(s) that are
self-administered by the subject in a nasal formulation between two and six times daily to
maintain a therapeutically effective elevated and lowered pulsatile level of Y2 receptor-
binding peptide during an 8 hour to 24 hour extended dosing period.
Kits
The instant invention also includes kits, packages and multicontainer units containing
the above described pharmaceutical compositions, active ingredients, and/or means for
administering the same for use in the prevention and treatment of diseases and other
conditions in mammalian subjects. Briefly, these kits include a container or formulation that
contains one or more Y2 receptor-binding peptide proteins, analogs or mimetics, and/or other
biologically active agents in combination with mucosal delivery enhancing agents disclosed
herein formulated in a pharmaceutical preparation for mucosal delivery.
The intranasal formulations of the present invention can be administered using any
spray bottle or syringe. An example of a nasal spray bottle is the, "Nasal Spray Pump w/
Safety Clip, Pfeiffer SAP # 60548, which delivers a dose of 0.1mL per squirt and has a
diptube length of 36.05 mm. It can be purchased from Pfeiffer of America of Princeton, NJ.
Intranasal doses of a Y2 receptor-binding peptide such as PYY can range from 0.1 µg/kg to
about 1500 fig/kg. When administered in as an intranasal spray, it is preferable that the
particle size of the spray are between 10 - 100 mm (microns) in size, preferably 20-100 urn
in size.
To promote weight loss, an intranasal dose of a Y2 receptor-binding peptide PYY is
administered at dose high enough to promote satiety but low enough so as not to induce any
unwanted side-effects such as nausea. A preferred intranasal dose of a Y2 receptor-binding
peptide such as PYY(3-36) is about 3 mg - 10 µg/kg weight of the patient, most preferably
about 6 µg/kg weight of the patient. In a standard dose a patient will receive 50 µg to 800 ug,
more preferably about between 100 µg to 400 µg, most preferably 150 µg to about 200 µg.
The a Y2 receptor-binding peptide such as PYY(3-36) is preferably administered at least ten
minutes to one hour prior to eating to prevent nausea but no more than about twelve to
twenty-four hours prior to eating. The patient is dosed at least once a day preferably before
every meal until the patient has lost a desired amount of weight. The patient then receives
maintenance doses at least once a week preferably daily to maintain the weight loss."
As is shown by the data from the following examples, when administered intranasally
to humans using the Y2 receptor-binding peptide formulation of the present invention,
PYY(3-36) was found to reduce appetite. The examples also show that for the first time post-
prandial physiological levels of a PYY peptide could be reached through an intranasal route
of administration using the Y2 receptor-binding peptide formulations of the present invention
in which PYY(3-36) was the Y2 receptor-binding peptide.
The following examples are provided by way of illustration, not limitation.
An exemplary formulation for enhanced nasal mucosal delivery of peptide YY
following the teachings of the instant specification was prepared and evaluated as follows:
EXAMPLE 2
Nasal mucosal Delivery - Permeation Kinetics and Cytotoxicity
1. Organotypic Model
The following methods are generally useful for evaluating nasal mucosal delivery
parameters, kinetics and side effects for peptide YY within the formulations and method of
the invention, as well as for determining the efficacy and characteristics of the various
intranasal delivery-enhancing agents disclosed herein for combinatorial formulation or
coordinate administration with peptide YY.
Permeation kinetics and cytotoxicity are also useful for determining the efficacy and
characteristics of the various mucosal delivery-enhancing agents disclosed herein for
combinatorial formulation or coordinate administration with mucosal delivery-enhancing
agents. In one exemplary protocol, permeation kinetics and lack of unacceptable cytotoxicity
are demonstrated for an intranasal delivery-enhancing agent as disclosed above in
combination with a biologically active therapeutic agent, exemplified by peptide YY.
The EpiAirway system was developed by MatTek Corp (Ashland, MA) as a model of
the pseudostratified epithelium lining the respiratory tract. The epithelial cells are grown on
porous membrane-bottomed cell culture inserts at an air-liquid interface, which results in
differentiation of the cells to a highly polarized morphology. The apical surface is ciliated
with a microvillous ultrastructure and the epithelium produces mucus (the presence of mucin
has been confirmed by immunoblotting). The inserts have a diameter of 0.875 cm, providing
a surface area of 0.6 cm2. The cells are plated onto the inserts at the factory approximately
three weeks before shipping. One "kit" consists of 24 units.
A. On arrival, the units are placed onto sterile supports in 6-well microplates.
Each well receives 5 mL of proprietary culture medium. This DMEM-based medium is
serum free but is supplemented with epidermal growth factor and other factors. The medium
is always tested for endogenous levels of any cytokine or growth factor, which is being
considered for intranasal delivery, but has been free of all cytokines and factors studied to
date except insulin. The 5 mL volume is just sufficient to provide contact to the bottoms of
the units on their stands, but the apical surface of the epithelium is allowed to remain in direct
contact with air. Sterile tweezers are used in this step and in all subsequent steps involving
transfer of units to liquid-containing wells to ensure that no air is trapped between the
bottoms of the units and the medium.
B. The units in their plates are maintained at 37°C in an incubator in an
atmosphere of 5% CO2 in air for 24 hours. At the end of this time the medium is replaced
with fresh medium and the units are returned to the incubator for another 24 hours.
2. Experimental Protocol - Permeation Kinetics
A. A "kit" of 24 EpiAirway units can routinely be employed for evaluating
five different formulations, each of which is applied to quadruplicate wells. Each well is
employed for determination of permeation kinetics (4 time points), transepithelial resistance,
mitochondrial reductase activity as measured by MTT reduction, and cytolysis as measured
by release of LDH. An additional set of wells is employed as controls, which are sham
treated during determination of permeation kinetics, but are otherwise handled identically to
the test sample-containing units for determinations of transepithelial resistance and viability.
The determinations on the controls are routinely also made on quadruplicate units, but
occasionally we have employed triplicate units for the controls and have dedicated the
remaining four units in the kit to measurements of transepithelial resistance and viability on
untreated units or we have frozen and thawed the units for determinations of total LDH levels
to serve as a reference for 100% cytolysis.
B. In all experiments, the nasal mucosal delivery formulation to be studied is
applied to the apical surface of each unit in a volume of 100mL, which is sufficient to cover
the entire apical surface. An appropriate volume of the test formulation at the concentration
applied to the apical surface (no more than 100 mL is generally needed) is set aside for
subsequent determination of concentration of the active material by ELISA or other
designated assay.
C. The units are placed in 6 well plates without stands for the experiment:
each well contains 0.9 mL of medium which is sufficient to contact the porous membrane
bottom of the unit but does not generate any significant upward hydrostatic pressure on the
unit.
D. To minimize potential sources of error and avoid any formation of
concentration gradients, the units are transferred from one 0.9 mL-containing well to another
at each time point in the study. These transfers are made at the following time points, based
on a zero time at which the 100mL volume of test material was applied to the apical surface:
15 minutes, 30 minutes, 60 minutes, and 120 minutes.
E. In between time points the units in their plates are kept in the 37°C
incubator. Plates containing 0.9 mL medium per well are also maintained in the incubator so
that minimal change in temperature occurs during the brief periods when the plates are
removed and the units are transferred from one well to another using sterile forceps.
F. At the completion of each time point, the medium is removed from the well
from which each unit was transferred, and aliquotted into two tubes (one tube receives 700
mL and the other 200 mL) for determination of the concentration of permeated test material
and, in the event that the test material is cytotoxic, for release of the cytosolic enzyme, lactic
dehydrogenase, from the epithelium. These samples are kept in the refrigerator if the assays
are to be conducted within 24 hours, or the samples are subaliquotted and kept frozen at -
80°C until thawed once for assays. Repeated freeze-thaw cycles are to be avoided.
G. In order to minimize errors, all tubes, plates, and wells are prelabeled
before initiating an experiment.
H. At the end of the 120 minute time point, the units are transferred from the
last of the 0.9 mL containing wells to 24-well microplates, containing 0.3 mL medium per
well. This volume is again sufficient to contact the bottoms of the units, but not to exert
upward hydrostatic pressure on the units. The units are returned to the incubator prior to
measurement of transepithelial resistance.
3. Experimental Protocol - Transepithelial Resistance
A. Respiratory airway epithelial cells form tight junctions in vivo as well as in
vitro, restricting the flow of solutes across the tissue. These junctions confer a transepithelial
resistance of several hundred ohms x cm2 in excised airway tissues; in the MatTek EpiAirway
units, the transepithelial resistance (TER) is claimed by the manufacturer to be routinely
around 1000 ohms x cm2. We have found that the TER of control EpiAirway units which
have been sham-exposed during the sequence of steps in the permeation study is somewhat
lower (700-800 ohms x cm2), but, since permeation of small molecules is proportional to the
inverse of the TER, this value is still sufficiently high to provide a major barrier to
permeation. The porous membrane-bottomed units without cells, conversely, provide only
minimal transmembrane resistance (5-20 ohms x cm2).
B. Accurate determinations of TER require that the electrodes of the
ohmmeter be positioned over a significant surface area above and below the membrane, and
that the distance of the electrodes from the membrane be reproducibly controlled. The
method for TER determination recommended by MatTek and employed for all experiments
here employs an "EVOM"™ epithelial voltohmmeter and an "ENDOHM"™ tissue resistance
measurement chamber from World Precision Instruments, Inc., Sarasota, FL.
C. The chamber is initially filled with Dulbecco's phosphate buffered saline
(PBS) for at least 20 minutes prior to TER determinations in order to equilibrate the
electrodes.
D. Determinations of TER are made with 1.5 mL of PBS in the chamber and
350mL of PBS in the membrane-bottomed unit being measured. The top electrode is
adjusted to a position just above the membrane of a unit containing no cells (but containing
350 mL of PBS) and then fixed to ensure reproducible positioning. The resistance of a cell-
free unit is typically 5-20 ohms x cm2 ("background resistance").
E. Once the chamber is prepared and the background resistance is recorded,
units in a 24-well plate which had just been employed in permeation determinations are
removed from the incubator and individually placed in the chamber for TER determinations.
F. Each unit is first transferred to a petri dish containing PBS to ensure that the
membrane bottom is moistened. An aliquot of 350 uL PBS is added to the unit and then
carefully aspirated into a labeled tube to rinse the apical surface. A second wash of 350 uL
PBS is then applied to the unit and aspirated into the same collection tube.
G. The unit is gently blotted free of excess PBS on its exterior surface only
before being placed into the chamber (containing a fresh 1.5 mL aliquot of PBS). An aliquot
of 350 mL PBS is added to the unit before the top electrode is placed on the chamber and the
TER is read on the EVOM meter.
H. After the TER of the unit is read in the ENDOHM chamber, the unit is
removed, the PBS is aspirated and saved, and the unit is returned with an air interface on the
apical surface to a 24-well plate containing 0.3 mL medium per well.
I. The units are read in the following sequence: all sham-treated controls,
followed by all formulation-treated samples, followed by a second TER reading of each of
the sham-treated controls. After all the TER determinations are complete, the units in the 24-
well microplate are returned to the incubator for determination of viability by MTT reduction.
4. Experimental Protocol - Viability by MTT Reduction
MTT is a cell-permeable tetrazolium salt which is reduced by mitochondrial
dehydrogenase activity to an insoluble colored formazan by viable cells with intact
mitochondrial function or by nonmitochondrial NAD(P)H dehydrogenase activity from cells
capable of generating a respiratory burst. Formation of formazan is a good indicator of
viability of epithelial cells since these cells do not generate a significant respiratory burst.
We have employed a MTT reagent kit prepared by MatTek Corp for their units in order to
assess viability.
A. The MTT reagent is supplied as a concentrate and is diluted into a
proprietary DMEM-based diluent on the day viability is to be assayed (typically the afternoon
of the day in which permeation kinetics and TER were determined in the morning). Insoluble
reagent is removed by a brief centrifugation before use. The final MTT concentration is 1
mg/mL
B. The final MTT solution is added to wells of a 24-well microplate at a
volume of 300 mL per well. As has been noted above, this volume is sufficient to contact the
membranes of the EpiAirway units but imposes no significant positive hydrostatic pressure
on the cells.
C. The units are removed from the 24-well plate in which they were placed
after TER measurements, and after removing any excess liquid from the exterior surface of
the units, they are transferred to the plate containing MTT reagent. The units in the plate are
then placed in an incubator at 37°C in an atmosphere of 5% CO2 in air for 3 hours.
D. At the end of the 3-hour incubation, the units containing viable cells will
have turned visibly purple. The insoluble formazan must be extracted from the cells in their
units to quantitate the extent of MTT reduction. Extraction of the formazan is accomplished
by transferring the units to a 24-well microplate containing 2 mL extractant solution per well,
after removing excess liquid from the exterior surface of the units as before. This volume is
sufficient to completely cover both the membrane and the apical surface of the units.
Extraction is allowed to proceed overnight at room temperature in a light-tight chamber.
MTT extractants traditionally contain high concentrations of detergent, and destroy the cells.
E. At the end of the extraction, the fluid from within each unit and the fluid in
its surrounding well are combined and transferred to a tube for subsequent aliquotting into a
96-well microplate (200 mL aliquots are optimal) and determination of absorbance at 570 nm
on a VMax multiwell microplate spectrophotometer. To ensure that turbidity from debris
coming from the extracted units does not contribute to the absorbance, the absorbance at 650
nm is also determined for each well in the VMax and is automatically subtracted from the
absorbance at 570 nm. The "blank" for the determination of formazan absorbance is a 200
mL aliquot of extractant to which no unit had been exposed. This absorbance value is
assumed to constitute zero viability.
F. Two units from each kit of 24 EpiAirway units are left untreated during
determination of permeation kinetics and TER. These units are employed as the positive
control for 100% cell viability. In all the studies we have conducted, there has been no
statistically significant difference in the viability of the cells in these untreated units vs cells
in control units which had been sham treated for permeation kinetics and on which TER
determinations had been performed. The absorbance of all units treated with test
formulations is assumed to be linearly proportional to the percent viability of the cells in the
units at the time of the incubation with MTT. It should be noted that this assay is carried out
typically no sooner than four hours after introduction of the test material to the apical surface,
and subsequent to rinsing of the apical surface of the units during TER determination.
5. Determination of Viability by LDH Release
While measurement of mitochondrial reductase activity by MTT reduction is a
sensitive probe of cell viability, the assay necessarily destroys the cells and therefore can be
carried out only at the end of each study. When cells undergo necrotic lysis, their cytotosolic
contents are spilled into the surrounding medium, and cytosolic enzymes such as lactic
dehydrogenase (LDH) can be detected in this medium. An assay for LDH in the medium can
be performed on samples of medium removed at each time point of the two-hour
determination of permeation kinetics. Thus, cytotoxic effects of formulations which do not
develop until significant time has passed can be detected as well as effects of formulations
which induce cytolysis with the first few minutes of exposure to airway epithelium.
A. The recommended LDH assay for evaluating cytolysis of the EpiAirway
units is based on conversion of lactate to pyruvate with generation of NADH from NAD.
The NADH is then reoxidized along with simultaneous reduction of the tetrazolium salt INT,
catalyzed by a crude "diaphorase" preparation. The formazan formed from reduction of INT
is soluble, so that the entire assay for LDH activity can be carried out in a homogenous
aqueous medium containing lactate, NAD, diaphorase, and INT.
B. The assay for LDH activity is carried out on 50mL aliquots from samples
of "supernatant" medium surrounding an EpiAirway unit and collected at each time point.
These samples were either stored for no longer than 24 h in the refrigerator or were thawed
after being frozen within a few hours after collection. Each EpiAirway unit generates
samples of supernatant medium collected at 15 min, 30 min, 1 h, and 2 h after application of
the test material. The aliquots are all transferred to a 96 well microplate.
C. A 50 mL aliquot of medium which had not been exposed to a unit serves as
a "blank" or negative control of 0% cytotoxicity. We have found that the apparent level of
"endogenous" LDH present after reaction of the assay reagent mixture with the unexposed
medium is the same within experimental error as the apparent level of LDH released by all
the sham-treated control units over the entire time course of 2 hours required to conduct a
permeation kinetics study. Thus, within experimental error, these sham-treated units show no
cytolysis of the epithelial cells over the time course of the permeation kinetics measurements.
D. To prepare a sample of supernatant medium reflecting the level of LDH
released after 100% of the cells in a unit have lysed, a unit which had not been subjected to
any prior manipulations is added to a well of a 6-well microplate containing 0.9 mL of
medium as in the protocol for determination of permeation kinetics, the plate containing the
unit is frozen at -80°C, and the contents of the well are then allowed to thaw. This freeze-
thaw cycle effectively lyses the cells and releases their cytosolic contents, including LDH,
into the supernatant medium. A 50 mL aliquot of the medium from the frozen and thawed
cells is added to the 96-well plate as a positive control reflecting 100% cytotoxicity.
E. To each well containing an aliquot of supernatant medium, a 50mL aliquot
of the LDH assay reagent is added. The plate is then incubated for 30 minutes in the dark.
F. The reactions are terminated by addition of a "stop" solution of 1 M acetic
acid, and within one hour of addition of the stop solution, the absorbance of the plate is
determined at 490 nm.
G. Computation of percent cytolysis is based on the assumption of a linear
relationship between absorbance and cytolysis, with the absorbance obtained from the
medium alone serving as a reference for 0% cytolysis and the absorbance obtained from the
medium surrounding a frozen and thawed unit serving as a reference for 100% cytolysis.
6. ELISA Determinations
The procedures for determining the concentrations of biologically active agents as test
materials for evaluating enhanced permeation of active agents in conjunction with coordinate
administration of mucosal delivery-enhancing agents or combinatorial formulation of the
invention are generally as described above and in accordance with known methods and
specific manufacturer instructions of ELISA kits employed for each particular assay.
Permeation kinetics of the biologically active agent is generally determined by taking
measurements at multiple time points (for example 15 min., 30 min., 60 min. and 120 min)
after the biologically active agent is contacted with the apical epithelial cell surface (which
may be simultaneous with, or subsequent to, exposure of the apical cell surface to the
mucosal delivery-enhancing agent(s)).
The procedures for determining the concentrations of peptide YY neuropeptide Y, and
pancreatic peptide in blood serum, central nervous system (CNS) tissues or fluids, cerebral
spinal fluid (CSF), or other tissues or fluids of a mammalian subject may be determined by
immunologic assay for peptide YY neuropeptide Y, and pancreatic peptide. The procedures
for determining the concentrations of peptide YY neuropeptide Y, and pancreatic peptide as
test materials for evaluating enhanced permeation of active agents in conjunction with
coordinate administration of mucosal delivery-enhancing agents or combinatorial formulation
of the invention are generally as described above and in accordance with known methods and
specific manufacturer instructions for radioimmunoassay (RIA), enzyme immunoassay
(EIA), and antibody reagents for immunohistochemistry or immunofluorescence for peptide
YY neuropeptide Y, and pancreatic peptide. Bachem AG (King of Prussia, PA).
TM
EpiAirway tissue membranes are cultured in phenol red and hydrocortisone free
medium (MatTek Corp., Ashland, MA). The tissue membranes are cultured at 37°C for 48
hours to allow the tissues to equilibrate. Each tissue membrane is placed in an individual well
of a 6-well plate containing 0.9 mL of serum free medium. 100 mL of the formulation (test
sample or control) is applied to the apical surface of the membrane. Triplicate or
quadruplicate samples of each test sample (mucosal delivery-enhancing agent in combination
with a biologically active agent, peptide YY) and control (biologically active agent, peptide
YY, alone) are evaluated in each assay. At each time point (15, 30, 60 and 120 minutes) the
tissue membranes are moved to new wells containing fresh medium. The underlying 0.9 mL
medium samples is harvested at each time point and stored at 4°C for use in ELISA and
lactate dehydrogenase (LDH) assays.
The ELISA kits are typically two-step sandwich ELISAs: the immunoreactive form of
the agent being studied is first "captured" by an antibody immobilized on a 96-well
microplate and after washing unbound material out of the wells, a "detection" antibody is
allowed to react with the bound immunoreactive agent. This detection antibody is typically
conjugated to an enzyme (most often horseradish peroxidase) and the amount of enzyme
bound to the plate in immune complexes is then measured by assaying its activity with a
chromogenic reagent. In addition to samples of supernatant medium collected at each of the
time points in the permeation kinetics studies, appropriately diluted samples of the
formulation (i.e., containing the subject biologically active test agent) that was applied to the
apical surface of the units at the start of the kinetics study are also assayed in the ELISA
plate, along with a set of manufacturer-provided standards. Each supernatant medium sample
is generally assayed in duplicate wells by ELISA (it will be recalled that quadruplicate units
are employed for each formulation in a permeation kinetics determination, generating a total
of sixteen samples of supernatant medium collected over all four time points).
A. It is not uncommon for the apparent concentrations of active test agent in
samples of supernatant medium or in diluted samples of material applied to the apical surface
of the units to lie outside the range of concentrations of the standards after completion of an
ELISA. No concentrations of material present in experimental samples are determined by
extrapolation beyond the concentrations of the standards; rather, samples are rediluted
appropriately to generate concentrations of the test material which can be more accurately
determined by interpolation between the standards in a repeat ELISA.
B. The ELISA for a biologically active test agent, for example, peptide YY, is
unique in its design and recommended protocol. Unlike most kits, the ELISA employs two
monoclonal antibodies, one for capture and another, directed towards a nonoverlapping
determinant for the biologically active test agent, e.g., peptide YY, as the detection antibody
(this antibody is conjugated to horseradish peroxidase). As long as concentrations of peptide
YY that lie below the upper limit of the assay are present in experimental samples, the assay
protocol can be employed as per the manufacturer's instructions, which allow for incubation
of the samples on the ELISA plate with both antibodies present simultaneously. When the
peptide YY levels in a sample are significantly higher than this upper limit, the levels of
immunoreactive peptide YY may exceed the amounts of the antibodies in the incubation
mixture, and some peptide YY which has no detection antibody bound will be captured on
the plate, while some peptide YY which has detection antibody bound may not be captured.
This leads to serious underestimation of the peptide YY levels in the sample (it will appear
that the peptide YY levels in such a sample lie significantly below the upper limit of the
assay). To eliminate this possibility, the assay protocol has been modified:
B.1. The diluted samples are first incubated on the ELISA plate containing the
immobilized capture antibody for one hour in the absence of any detection antibody. After
the one hour incubation, the wells are washed free of unbound material.
B.2. The detection antibody is incubated with the plate for one hour to permit
formation of immune complexes with all captured antigen. The concentration of detection
antibody is sufficient to react with the maximum level of peptide YY which has been bound
by the capture antibody. The plate is then washed again to remove any unbound detection
antibody.
B.3. The peroxidase substrate is added to the plate and incubated for fifteen
minutes to allow color development to take place.
B.4. The "stop" solution is added to the plate, and the absorbance is read at
450 nm as well as 490 nm in the VMax microplate spectrophotometer. The absorbance of the
colored product at 490 nm is much lower than that at 450 nm, but the absorbance at each
wavelength is still proportional to concentration of product. The two readings ensure that the
absorbance is linearly related to the amount of bound peptide YY over the working range of
the VMax instrument (we routinely restrict the range from 0 to 2.5 OD, although the
instrument is reported to be accurate over a range from 0 to 3.0 OD). The amount of peptide
YY in the samples is determined by interpolation between the OD values obtained for the
different standards included in the ELISA. Samples with OD readings outside the range
obtained for the standards are rediluted and run in a repeat ELISA.
RESULTS
Measurement of transepithelial resistance by TER Assay: After the final assay time points,
membranes were placed in individual wells of a 24 well culture plate in 0.3 mL of clean
medium and the trans epithelial electrical resistance (TER) was measured using the EVOM
Epithelial Voltohmmeter and an Endohm chamber (World Precision Instruments, Sarasota,
FL). The top electrode was adjusted to be close to, but not in contact with, the top surface of
the membrane. Tissues were removed, one at a time, from their respective wells and basal
surfaces were rinsed by dipping in clean PBS. Apical surfaces were gently rinsed twice with
PBS. The tissue unit was placed in the Endohm chamber, 250 mL of PBS added to the insert,
the top electrode replaced and the resistance measured and recorded. Following
measurement, the PBS was decanted and the tissue insert was returned to the culture plate.
All TER values are reported as a function of the surface area of the tissue.
The final numbers were calculated as:
TER of cell membrane = (Resistance (R) of Insert with membrane - R of
blank Insert) X Area of membrane (0.6 cm2).
The effect of pharmaceutical formulations comprising peptide YY and intranasal
delivery-enhancing agents on TER measurements across the EpiAirway™ Cell Membrane
(mucosal epithelial cell layer) is shown in Figure 1. A decrease in TER value relative to the
control value (control = approximately 1000 ohms-cm2; normalized to 100.) indicates a
decrease in cell membrane resistance and an increase in mucosal epithelial cell permeability.
Exemplary peptide YY formulation, Formulation P, showed the greatest decrease in
cell membrane resistance. (Table 2). The results indicate that the exemplary formulation
(e.g., Formulation P) reduces the resistance of the membrane to less than 1% of the control at
the concentrations tested. The values shown are the average of three replicates of each
formulation. Formulations A and B are controls prepared by reconstituting peptide YY
(Bachem AG, King of Prussia, PA) containing 60mg peptide Y3.36 in 100 ml of phosphate
buffered saline (PBS) at pH 7.4 or 5.0. Peptide YY without mucosal delivery enhancers did
not decrease the resistance.
The results indicate that an exemplary formulation for enhanced intranasal delivery of
peptide YY (e.g., Formulation P) decreases cell membrane resistance and significantly
increases mucosal epithelial cells permeability. The exemplary formulations will enhance
intranasal delivery of peptide YY to the blood serum or to the central nervous system tissue
or fluid. The results indicate that these exemplary formulations when contacted with a
mucosal epithelium yield significant increases in mucosal epithelial cell permeability to
peptide YY.
Influence of Pharmaceutical Formulations Comprising Peptide YY and
Intranasal Delivery-Enhancing Agents on Transepithelial Resistance (TER)
of EpiAirway Cell Membrane
Permeation kinetics as measured by ELISA Assay: The effect of pharmaceutical
formulations of the present invention comprising peptide YY and intranasal delivery-
enhancing agents on the permeation of peptide YY across the EpiAirway™ Cell Membrane
(mucosal epithelial cell layer) is measured as described above. The results are shown in
Table 3. Permeation of peptide YY across the EpiAirway™ Cell Membrane is measured by
ELISA assay.
For the exemplary intranasal formulations (e.g., Formulation P) of the present
invention, the greatest increase in peptide YY permeation occurred in Formulation P as
shown in Table 3. The procedure uses an ELISA assay to determine the concentration of
biologically active peptide YY that has permeated the epithelial cells into the surrounding
medium over multiple time points. The results show increased permeation of peptide YY in
Formulation P compared to Formulation A or B (peptide YY control formulation; 60 mg
peptide YY3-36 in 100 ml of phosphate buffered saline (PBS) at pH 7.4 or 5.0; Bachem AG,
King of Prussia, PA). On average the cumulative increase in permeation at 120 minutes
using Formulation P exemplary intranasal formulation is about 1195 fold greater than
Formulations A or B controls.
MTTAssay: The MTT assays were performed using MTT-100, MatTek kits. 300 mL of
the MTT solution was added into each well. Tissue inserts were gently rinsed with clean
PBS and placed in the MTT solution. The samples were incubated at 370C for 3 hours.
After incubation the cell culture inserts were then immersed with 2.0 mL of the extractant
solution per well to completely cover each insert. The extraction plate was covered and
sealed to reduce evaporation. Extraction proceeds overnight at RT in the dark. After the
extraction period was complete, the extractant solution was mixed and pipetted into a 96-
well microtiter plate. Triplicates of each sample were loaded, as well as extractant blanks.
The optical density of the samples was then measured at 550 run on a plate reader
(Molecular Devices).
The MTT assay on an exemplary formulation for enhanced nasal mucosal
delivery of peptide YY following the teachings of the instant specification (e.g.,
Formulation P) compared to control formulation (Formulations A or B) are shown in
Table 4. The results for formulations comprising peptide YY and one or more intransal
delivery enhancing agents, for example, Formulation P (experiment performed in three
replicates) indicate that there is minimal toxic effect of this exemplary embodiment on
viability of the mucosal epithelial tissue.
EXAMPLE 3
Formulation P (Peptide YY) of the Present Invention In Combination With
Triamcinolone Acetonide Corticosteroid Improves Cell Viability
The present example provides an in vitro study to determine the permeability and
reduction in epithelial mucosal inflammation of an intranasally administered peptide YY,
for example, human peptide YY, in combination with a steroid composition, for example,
triamcinolone acetonide, and further in combination with one or more intranasal delivery-
enhancing agents. The study involves determination of epithelial cell permeability by
TER assay and reduction in epithelial mucosal inflammation as measured by cell viability
in an MTT assay by application of an embodiment comprising peptide YY and
triamcinolone acetonide.
Formulation P (see Table 1 above) is combined in a formulation with
triamcinolone acetonide at a dosage of 0.5, 2.0, 5.0, or 50 mg. Normal dose of
triamcinolone acetonide, (Nasacort , Aventis Pharmaceuticals) for seasonal allergic
rhinitis, is 55 mg per spray. Formulation P in combination with triamcinolone acetonide
corticosteroid improves cell viability as measured by the MTT assay, while maintaining
epithelial cell permeability as measured by TER and ELISA assays.
According to the methods and formulations of the invention, measurement of
permeability of Formulation P in the presence or absence of triamcinolone acetonide is
performed by transepithelial electrical resistance (TER) assays in an EpiAirway™ cell
membrane. TER assays of Formulation P plus triamcinolone acetonide at a concentration
of 0.5, 2.0, 5.0, or 50 mg per spray indicate that peptide YY permeability did not decrease
and was equal to permeability of Formulation P alone. Formulation P plus triamcinolone
acetonide at a triamcinolone acetonide concentration between 0 and 50 µg per spray is
typically, at least 10-fold to 100-fold greater than permeability of Formulations A or B
(peptide YY control).
According to the methods and formulations of the invention, measurement of
permeability of Formulation P in the presence or absence of triamcinolone acetonide is
performed by ELISA assay in an EpiAirway™ cell membrane. Similar to the TER assay
above, ELISA assay of Formulation P plus triamcinolone acetonide at a concentration of
0.5, 2.0, 5.0, or 50mg per spray indicate that peptide YY permeability did not decrease
and was equal to permeability of Formulation P alone. Formulation P plus triamcinolone
acetonide at a triamcinolone acetonide concentration between 0 and 50 mg per spray is
typically greater than permeability of Formulations A or B (peptide YY control).
According to the methods and formulations of the invention, MTT assay
measured cell viability of Formulation P in the presence or absence of triamcinolone
acetonide. Typically, addition of triamcinolone acetonide (at a concentration of 0.5, 2.0,
5.0, or 50 mg per spray) to Formulation P improves cell viability compared to
Formulation P in the absence of triamcinolone acetonide.
Addition of triamcinolone acetonide to Formulation P increases cell viability and
maintains epithelial permeability as measured by TER assay comparable to Formulation
P in the absence of triamcinolone acetonide.
Reduction in epithelial mucosal inflammation of an intranasally administered
peptide YY is accomplished with an intranasal formulation of peptide YY in combination
with one or more steroid or corticosteroid compound(s) typically high potency
compounds or formulations, but also in certain cases medium potency, or low potency
compounds or formulations. Overall potency (equivalent dosages) of high, medium, and
low potency steroids are given. Typically, an intranasal formulation of peptide YY in
combination with a high potency steroid composition includes, but is not limited to,
betamethasone (0.6 to 0.75 mg dosage), or dexamethasone (0.75 mg dosage). In an
alternative formulation, an intranasal formulation of peptide YY in combination with a
medium potency steroid composition includes, but is not limited to, methylprednisolone
(4 mg dosage), triamcinolone (4 mg dosage), or prednisolone (5 mg dosage). In a further
alternative formulation, an intranasal formulation of peptide YY in combination with a
low potency steroid composition includes, but is not limited to hydrocortisone (20 mg
dosage) or cortisone (25 mg dosage).
Example 4
Preparation of a PYY Formulation Free of a Stabilizer that is a Protein
A PYY formulation suitable for intranasal administration of PYY, which was
substantially free of a stabilizer that is a protein was prepared having the formulation
listed below.
1. About 3/4 of the water was added to a beaker and stirred with a stir bar on a stir
plate and the sodium citrate was added until it was completely dissolved.
2. The EDTA was then added and stirred until it was completely dissolved.
3. The citric acid was then added and stirred until it was completely dissolved.
4. The methyl-ß-cyclodextrin was added and stirred until it was completely
dissolved.
5. The DDPC was then added and stirred until it was completely dissolved.
6. The lactose was then added and stirred until it was completely dissolved.
7. The sorbitol was then added and stirred until it was completely dissolved.
8. The chlorobutanol was then added and stirred until it was completely
dissolved.
9. The PYY 3-36 was added and stirred gently until it dissolved.
10. 11 Check the pH to make sure it is 5.0 ± 0.25. Add dilute HC1 or dilute
NaOH to adjust the pH.
11. Add water to final volume.
112
Example 7
Intranasal Formulation Development
Peptides and proteins are relatively fragile molecules compared to low-molecular-weight
therapeutics. The objective of the formulation development phase was to identify a
candidate formulation suitable for intranasal delivery. In order to achieve this goal,
numerous candidates were tested in order to identify a formulation with acceptable drug
stability, delivery across the nasal mucosa, toxicity and preservative effectiveness.
Initially, the effect of pH was examined. Figure 1 shows the stability of PYY 3-36 at high
temperature (40 °C) at various pHs from 3.0 to 7.4. At physiological pH, there was
substantial loss of drug at elevated temperature. Best stability was achieved at about pH
5.0. This pH was chosen for further formulation optimization.
In order to further optimize stability, various stabilizing agents were tested for their
ability to facilitate passage of drug across the nasal mucosa. The enhancers tested were
chosen based on their ability to open tight junctions with limited cellular toxicity. To
accomplish this, a primary human epithelial cell model (EpiAirway, MatTek, Inc.,
Ashland MA) was employed. This cell line forms a pseudo-stratified columnar epithelial
cell layer with tight junctions similar to the respiratory epithelium found in the nose.
Drug formulations were placed on the apical side of the tissue layer, and drug
quantitation carried out for the basal media. The extent of tight junction opening was
measured by decrease in the transepithelial electrical resistance (TEER). Cell viability
and cytotoxicity were monitored by MTT and LDH assays, respectively. Data from a
representative screening experiment are depicted in Figures 2-5.
Figure 2 shows the data for TEER. In some cases there was little or no decrease in TEER
compared to the control, indicating tight junctions which remain closed. In other cases
there was a substantial drop in TEER indicating tight junction opening. The results
demonstrate that the in vitro cell model is capable of discriminating the ability of
different formulations to open the tight junctions.
In the candidate formulations tested the cell viabilities (Figure 3; MTT) were good and
cyctotoxicities (Figure 4; LDH) were low.
In total, over 200 different formulations were tested, reflecting the high-throughput
nature of the in vitro screening model. Using all the available data. a multivariate
analysis was conducted to elucidate the effect each formulation component exerted on
each of the 7 output variables (drug permeability, osmolality, stability at refrigerated and
accelerated conditions, TEER, and MTT and LDH assays). The multivariate analysis
consisted of an initial analysis of each formulation component for some level of
correlation with output parameters (p regression or stepwise logistic selection model was used. The results suggest that one
excipient correlated to osmolality and toxicity (r2 = 0.91 and 0.27, respectively), two
correlated to PYY3-36 permeation (r2 = 0.44), three affected stability (r2 = 0.24), and five
impacted paracellular resistance (r2 = 0.55). The best formulations determined by this
process increased at least 30-75 fold the PYY 3-36 transport compared to simple buffer
solutions.
Based on these analyses, an optimized PYY 3-36 formulation was selected for further
development. This optimized formulation contained two stabilizers, two permeation
enhancers, one chelating agent, and one preservative in a sodium acetate buffer, pH 5.0.
This formulation passed the USP Preservative Effectiveness Test. The synergistic
contributions of the various components on drug permeation is presented in Figure 5.
Compared to simple buffer formulations at the same osmolality, the optimized
formulation exhibits more than 100-fold increased drug permeation.
Finally, pre-clinical and clinical batches of the optimized formulation were prepared and
placed on stability at 5 °C and 25 °C in the final product packaGlng. Preliminary data,
depicted in Table 8 reveal essentially no loss of drug at one month at either 5 °C or 25
°C.
Preclinical Studies
To date, a series of six preclinical studies in rats, rabbits, and dogs have been completed.
Plasma PYY3-36 levels in all species were determined by a validated proprietary
radioimmunoassay method.
Bioavailability (the molar fraction of drug identified in plasma divided by the amount
administered nasally) in rats was determined to be approximately 6%, and in rabbits is
approximately 8%. These values may understate the true bioavailability, as any peptide
degradation in plasma before sampling, or degradation after sampling despite the
presence of a proteinase inhibitor, will decrease the measured bioavailability.
Nasal toxicity has been evaluated in rat and rabbit models for up to 14 consecutive days
at doses 50x the expected human clinical dose on a mg/kg basis. There were no
microscopic or gross pathological findings related to the test article. There were no
clinical observations.
Systemic toxicity following intravenous administration was evaluated in rat and rabbit
models. At IV doses up to approx 160x the expected human dose (400 ug/kg in the rat
and 205 ug/kg in the rabbit) there were no test article related microscopic or macroscopic
findings.
Cardiovascular toxicity was assessed in the anesthetized dog model in a dose ranGlng
study design. The highest dosage, an infusion of PYY3-36 up to 24ug/kg over 60 minutes
corresponded to 33x the expected human dose on a body surface area basis. The resultan
plasma levels, 30 ng/mL, was approximately 380x the basal canine plasma level. At this
plasma level, there was no effect on arterial blood pressure, femoral blood flow, or QTc
and only minor changes in heart rate (increase from 123 to 148 bpm mean) and
respiratory rate (decrease from 54 to 36) were noted.
Pharmacokinetic data was collected in these preclinical studies. From one study in rats,
the plasma levels following intranasal administration at various doses are shown in
Figures 6, 7and 8. Figure 6 shows PYY3-36 is seen in the plasma within 5 minutes, peak
plasma concentrations (Tmax) are reached in 10-15 minutes, and the terminal eliminatior
half life is approx 15 minutes. Both Cmax and AUCo-tare linear with respect to intranasal
dose.
Clinical Studies
A dose ranGlng clinical trial has been initiated with the goal of establishing safety, PK,
and bioavailability of the intranasal formulation of PYY3-36. To date, patients have been
enrolled in the first two of five dose cohorts. One patient reported a taste in the back of
his throat; there have been no other adverse events to date.
Conclusion
Formulation, preclinical, and initial clinical work have begun on an intranasal
formulation of PYY3.36. The approach to formulation has resulted in a more than one
hundred fold increase in transmembrane permeability of this 4 kD peptide with no
increase in cellular toxicity. Preclinical studies have demonstrated a considerable safety
marGln for nasal, cardiovascular, and systemic toxicity for PYY3.36. On the basis on the
ongoing dose ranGlng clinical studies, chronic administration weight loss studies are
planned.

Example 8a
CLINICAL PROTOCOL
NASAL ABSORPTION OF INTRANASAL PEPTIDE YY3-36 (PYY3-36) IN
HEALTHY HUMAN SUBJECTS
Object of the present study:
The object of the present study was to evaluate the absorption of intranasally
administered PYY3-36 into the blood stream from the nose. This was a phase I, in clinic,
single dose, doses escalation study involving fasted, normal, healthy male and female
volunteers. Ascending doses of intranasal PYY3-36 were evaluated between 20 µg to
200 µg to evaluate safety, nasal tolerance and absorption of PYY3-36. Assessment of
appetite sensation in each individual was also evaluated.
PYY3-36 was administered to 15 healthy humans divided into 5 Groups of 3
individuals each.
Group I.
The first group was administered by an intranasal spray 20 µg of PYY3-36 in a 0.1 ml
solution.
Group II
The second group received intranasally 50 µg of PYY3.36 in a 0.1 ml solution.
Group III
The third group received intranasally 100 µg of PYY3.36 in a 0.1 ml solution.
Group IV
The fourth group received intranasally 150 µg of PYY3-36 in a 0.1 ml solution.
Group V
The fifth group received intranasally 200 µg of PYY3-36 in a 0.1 ml solution.
Blood samples were taken collected and the plasma concentrations of PYY were
determined at 0 (i.e., pre-dose), 5, 7.5, 10, 15, 20, 30, 45, 60 minutes post-dose. The
subjects were then fed and a blood sample taken and the concentration of PYY was
determined 30 minutes postprandial. Plasma concentrations of PYY3-36 were determined
using a validated analytical procedure.
For each subject, the following PK parameters were calculated, whenever
possible, based on the plasma concentrations of PYY3.36, according to the model
independent approach:
Cmax Maximum observed concentration.
tmax Time to maximum concentration.
AUCo-t Area under the concentration-time curve from time 0 to the
time of last measurable concentration, calculated by the
linear trapezoidal rule.
The following parameters were calculated when the data permits accurate estimation of
these parameters:
AUC0-oo Area under the concentration-time curve extrapolated to
infinity, calculated using the formula:

where Ct is the last measurable concentration and Ke is the
apparent terminal phase rate constant.
Ke Apparent terminal phase rate constant, where Ke is the
magnitude of the slope of the linear regression of the log
concentration versus time profile during the terminal phase.
t1/2 Apparent terminal phase half-life (whenever possible),
where t1/2 = (1n2)/Ke.
PK calculations were performed using commercial software such as WinNonlin
(Pharsight Corporation, Version 3.3, or higher). The results are shown in the graphs
below.
Discussion and Conclusion.
Background:
Each dosing group included three subjects who were dosed intranasally once with a
formulation of this invention that contained a specified dose of synthetic, pyrogen-free
human PYY 3-36. Five dosing groups were organized, with escalating doses of PYY 3-36
in the formulation. Blood samples were drawn at specified intervals into blood collection
tubes that contained lithium heparin (to inhibit coagulation) and aprotinin (to preserve
PYY 3-36). Plasma from each blood sample was collected by centrifugation and stored in
frozen aliquots. One frozen aliquot of each blood sample was shipped to Nastech
Analytical Services and arrived frozen. Each sample was stored frozen until assayed for
PYY concentration by radioimmunoassay (RIA).
Observations:
Group 1: This group of subjects was dosed with 20 micrograms of PYY 3-36. Plasma
PYY concentrations for the subjects varied from a minimum of "less than 20 pg/ml"
(below the lower limit of quantitation of the radioimmunoassay) to a maximum of 159
pg/ml. The trends of concentrations observed are not consistent with significant
absorption of drug into the blood of the subjects studied.
Group 2: This group of subjects was dosed with 50 micrograms of PYY 3-36. Plasma
PYY concentrations for the subjects varied from a minimum of 50 pg/ml to a maximum
of 255 pg/ml. The trends of concentrations observed are consistent with significant
absorption of drug into the blood of the subjects studied.
Group 3: This group of subjects was dosed with 100 micrograms of PYY 3-36. Plasma
PYY concentrations for the subjects varied from a minimum of 87 pg/ml to a maximum
of 785 pg/ml. The trends of concentrations observed are consistent with significant
absorption of drug into the blood of the subjects studied.
Group 4: This group of subjects was dosed with 150 micrograms of PYY 3-36. Plasma
PYY concentrations for the subjects varied from a minimum of 45 pg/ml to a maximum
of 2022 pg/ml. The trends of concentrations observed are consistent with significant
absorption of drug into the blood of the subjects studied.
Group 5: This group of subjects was dosed with 200 micrograms of PYY 3-36. Plasma
PYY concentrations for the subjects varied from a minimum of 48 pg/ml to a maximum
of 1279 pg/ml. The trends of concentrations observed are consistent with significant
absorption of drug into the blood of the subjects studied.
These results are consistent with a dose dependent absorption of PYY3-36.
Additional Observations and data:
Summary of findings:
• At intranasal doses of 50 µg - 200 µg, there is dose dependent plasma uptake of
PYY.
• The duration of elevated plasma concentrations is considerably longer than would
have been predicted, with an elimination half life calculated at 55 minutes.
• Cmax and AUC 0-t show good linearity with dose.
• There is considerable inter-subject variability at a given dose.
• Surprisingly, this study failed to detect postprandial elevation of PYY although
the quantity of food actually eaten was not measured and if too little was eaten
could explain the observations.
• Visual-analog scale hunger questions suggest decreased hunger with increasing
doses of PYY.
• Nausea and lightheadedness appear to be related to very high plasma
concentration of PYY.
• Values based on the assay described in this specification appear to be 2-3x higher
than those previously reported in the literature.
Notes:
• In some cases pMol/L are used as the PYY measurement units; in other analyses,
pg/mL are used. The conversion factor is pmol/L * 4.05 = pg/mL.
• In some cases, the 150-minute time point is displayed in plots. Strictly speaking,
this is a postprandial datapoint, and may therefore confound PK evaluation.
However, an unexpected finding described in more detail below is that the 30
minute postprandial timepoint is no different from the baseline value.
The Tmax of 24 minutes is typical for a nasal product. The elimination half life of 55
minutes is considerably longer than would have been expected. Literature references
indicated a t1/2 typically of 5-10 minutes. The elimination half life may also be affected
by some continued uptake from the nasal mucosa occurring after the Tmax and by
formulation components that effect peptide metabolism. Alternatively, because the assay
described in this specification employs an extraction procedure, the assay will capture
both free and protein-bound PYY, whereas an assay which does not use an extraction
may assay primarily the free fraction.
From this analysis of mean VAS change from baseline (mean of 10, 30, and 60 minute
values minus baseline) vs dose, one observes:
Example 9
Buccal formulation of PYY3-36
(Prophetic)
Bilayer tablets are prepared in the following manner. An adhesive layer is
prepared by weighing 70 parts by weight polyethylene oxide (Polyox 301N; Union
Carbide), 20 parts by weight polyacrylic acid (Carbopol 934P; B.F. Goodrich), and 10
parts by weight of a compressible xylitol/carboxymethyl cellulose filler (Xylitab 200;
Xyrofin). These ingredients are mixed by rolling in ajar for 3 minutes. The mixture is
then transferred to an evaporating dish and quickly wet granulated with absolute ethanol
to a semi-dough-like consistency. This mass is immediately and rapidly forced through a
14 mesh (1.4 mm opening) stainless steel screen, to which the wet granules adhered. The
screen is covered with perforated aluminum foil, and the wet granules are dried overnight
at 30° C. The dried granules are removed from the screen and then passed through a 20
mesh (0.85 mm opening) screen to further reduce the size of the granules. Particles that
do not pass through the 20 mesh screen are ground briefly with a mortar and pestle to
minimize the amount of fines and then passed through the 20 mesh screen. The resulting
granules are then placed in a mixing jar, and 0.25 parts by weight stearic acid and 0.06
parts by weight mint flavor (Universal Flavors) are added and blended to the granules.
The final percentages by weight of the ingredients are thus 69.78% polyethylene oxide,
9.97% compressible xylitol/carboxymethyl cellulose filler, 19.94% polyacrylic acid,
0.25% stearic acid, and 0.06% mint flavor. A 50 mg amount of this mixture is placed on a
0.375 inch diameter die and precompressed on a Carver Press Model C with 0.25 metric
ton pressure for a 3 second dwell time to form the adhesive layer.
The active layer is prepared by weighing 49.39 parts by weight of mannitol, 34.33
parts by weight of hydroxypropyl cellulose (Klucel L F; Aqualon, Wilmington, Del.) and
15.00 parts by weight of sodium taurocholate (Aldrich, Milwaukee, Wis.), and mixing by
rolling in ajar for 3 minutes. The mixture is then transferred to an evaporating dish and
quickly wet granulated with absolute ethanol to a semi-dough-like consistency. This mass
is immediately and rapidly forced through a 14 mesh stainless steel screen, to which the
wet granules adher. The screen is covered with perforated aluminum foil, and the
granules dried at 30° C. The dried granulation is then passed sequentially through 20, 40
(0.425 mm opening), and 60 (0.25 mm opening) mesh screens to reduce particle size
further. Particles that do not pass through a screen are briefly ground with a mortar and
pestle to minimize fines and then passed through the screen. The screened particles were
weighed, and then 0.91 parts by weight of PYY3-36 and 0.06 parts by weight of FD&C
yellow #6HT aluminum lake dye are sequentially blended with the dry granulation by
geometric dilution. The dyed granulation is then placed in a mixing jar and blended with
0.25 parts by weight magnesium stearate (lubricant) and 0.06 parts by weight mint flavor
by rolling for 3 minutes. A 50 mg sample of this material is placed on top of the partially
compressed adhesive layer and both layers are then compressed at 1.0 ton pressure for a 3
second dwell time to yield a bilayer tablet suitable for buccal delivery.
This procedure results in a Glngival tablet wherein the active layer contains 0.91%
by weight of PYY3-36, 15% by weight of NaTC, and 84.09% by weight of filler,
lubricant, colorant, formulation aids, or flavoring agents.
Example 10
A study was conducted comparing the ability of endotoxin-free PYY 3-36 vs non-
endotoxin-free PYY 3-36 to permeate the bronchial epithelium according of to the
procedure of Example 1. It was determined that about twice the amount of enodotoxin-
free PYY3-36 permeated the bronchial epithelium as compared to PYY3-36 formulation
that contained endotoxin.
Both formulations contained Chlorobutanol 2.5mg/ml, 2.mg/ml of DDPC, 10
mg/ml of albumin, lmg/ml of EDTA and 45 mg/ml of M-B-CD. One formulation
contained endotoxin-free PYY3-36 and the other formulation contained 70 EUs or
greater of endotoxin.
The average MTT of the PYY3-36 formulation containing endotoxin was 91.72%
while the endotoxin-free PYY3-36 formulation had an average MTT of 100.16%.
The average permeation of the PYY3-36 formulation containing endotoxin was
5.36%, while the average permeation of the endotoxin-free PYY3-36 formulation was
10.75%.
A number of known mucosal delivery enhancing excipients can be effectively
combined with endotoxin-free Y2 receptor binding peptides, especially endotoxin-free
PYY3-36, and can be used to improve non-infusion formulations, especially oral
delivery. Such excipients are contained in the following patent applications that are
incorporated by reference: US Patent applications 20030225300, 20030198658,
20030133953, 20030078302, 20030045579, 20030012817, 20030012817, 20030008900,
20020155993, 20020127202, 20020120009, 20020119910, 20020065255, 20020052422,
20020040061, 20020028250, 20020013497, 20020001591, 20010039258, 20010003001.
Oral Formulation of a Y2 Receptor-Binding Peptide
An oral formulation of a Y2 receptor-binding peptide can be prepared according
to the following procedure. A preferred formulation for oral delivery contains
approximately 0.5 mg/kg endotoxin-free PYY and between 100 and about 200 mg/kg of
one or more mucosal delivery enhancing excipients.
(Prophetic)
Example 11
Preparation of N-cyclohexanovlphenylalanine Aldehyde:
Phenylalanine methyl ester (1 g., 0.0046 moles) is dissolved in pyridine 5 mL.
Cyclohexanoyl chloride (0.62 mL) is added and the mixture is stirred for 2 hours. The
reaction mixture is poured onto hydrochloric acid (1N) and crushed ice. The aqueous
mixture is extracted twice with toluene. The combined toluene extracts are concentrated
in vacuo to give 1.1 g of crude N-cyclohexanoylphenylalanine methyl ester.
N-Cyclohexanoylphenylalanine methyl ester (0.5 g) is dissolved in ethylene
glycol dimethyl ether (20 mL). The solution is cooled to 70° C. and diisobutylaluminum
hydride (2.04 mL of a 1.5M solution in toluene) is added. The resulting reaction mixture
is stirred at -70° C. for 2 hours. The reaction is quenched by dropwise addition of 2N
hydrochloric acid. The mixture is extracted with cold ethyl acetate. The ethyl acetate
solution is washed with brine and dried over sodium sulfate. Concentration in vacuo
furnishes a white solid which is purified by silica gel chromatography. .1H NMR (300
MHz, DMSO-d6): 9.5 (s, 1H), 8.2 (d, 1H), 7.2 (m, 5H), 4.2 (m, 1H), 3.2 (d, 1H), 2.7 (d,
1H), 2.1 (m, 1H), 1.6 (br.m, 4H), 1.2 (br.m, 6H). R (KBr): 3300, 3050, 2900, 2850, 2800,
1700,1600,1500 cm-1.
Mass Spec.: M+l m/e 261.
Example 12
Preparation of N-acetylphenylalanine Aldehyde:
N-Acetylphenylalanine methyl ester (4.2 g, 19 mmol) is dissolved in ethylene
glycol dimethyl ether. The solution is cooled to -70° C. and diisobutylaluminum hydride
(25.3 mL of a 1.5M solution in toluene, 39 mmol) is added. The resulting reaction
mixture is stirred at -70° C. for 2 hours. The reaction is quenched by addition of 2N
hydrochloric acid. The mixture is extracted 4 times with cold ethyl acetate and 4 times
with toluene. The extracts are combined, washed with brine and dried over magnesium
sulfate. Concentration in vacuo followed by silica gel chromatography furnishes 2.7 g of
a white solid. The NMR is as reported in the literature, Biochemistry, 18: 921-926 (1979).
Example 13
Preparation of 3-acetamido-4-(p-hvdroxy)phenvl-2-butanone (N-acetvltvrosinone):
A mixture of tyrosine (28.9 g, 16 mmol), acetic anhydride (97.9 g, 96 mmol) and
pyridine (35 g, 16 mmol) are heated to 100° C. for 1 hour. The reaction mixture is
concentrated in vacuo to furnish a yellow oil. The oil is distilled at reduced pressure to
furnish 29.9 g or an oil.
1H NMR (DMSO-d6): NMR (d6-DMSO); 8.2 (d, 1H), 7.3 (d, 2H), 7.0 (d, 2H),
4.4 (m, 1H), 3.1 (dd, 1H), 2.7 (dd, 1H), 2.3 (s, 3H), 1.8 (s, 3H)
Example 14
Preparation of 3-acetamido-7-amino-2-butanone (N-acetyllysinone):
Following the procedure of Example 3 lysine is converted to N-acetyllysinone.
1H NMR (DMSO-d6): 8.1 (d, 1H), 7.8 (br.m. 1H), 4.1 (m, 1H), 3.0 (m, 2H), 2.0
(s, 3H), 1.9 (s, 3H) and 1.3 (br.m, 6H).
Example 15
Preparation of 3-acetamido-5-methyl-2-butanone (N-acetylleucinone):
Following the procedure of Example 3 leucine is converted to N-acetylleucinone.
1H NMR (DMSO-d6): 8.1 (d, 1H), 4.2 (m, 1H), 2.0 (s, 3H), 1.8 (s, 3H), 0.8 (d, 6H).
Example 16
Modification of 4-(4-aminophenyl)butyric Acid Using Benzene Sulfonyl Chloride
4-(4-Aminophenyl)butyric acid, (20 g 0.11 moles) is dissolved in 110 mL of
aqueous 2N sodium hydroxide solution. After stirring for about 5 minutes at room
temperature, benzene sulfonyl chloride (14.2 mL, 0.11 moles) is added dropwise into the
amino acid solution over a 15 minute period. After stirring for about 3 hours at room
temperature the mixture is acidified to pH 2 by addition of hydrochloric acid. This
furnishes a light brown precipitate which is isolated by filtration. The precipitate is
washed with warm water and dried. The melting point is 123-25° C.
If necessary, the modified amino acids can be purified by recrystallization and/or
chromatography.
Example 17
Modification of 4-amindbenzoic Acid Using Benzene Sulfonyl Chloride
Following the procedure of Example 6 4-aminobenzoic acid is converted to 4-
(phenylsulfonamido)benzoic acid.
Example 18
Modification of 4-aminophenylacetic Acid. 4-aminohippuric Acid, and 4-
aminomethylbenzoic Acid Using Benzene Sulfonyl Chloride
Following the procedure of Example 6, 4-aminophenylacetic acid, 4-
aminohippuric acid, and 4-amino-methylbenzoic acid are converted to 4-
(phenylsulfonamido)phenylacetic acid, 4-(phenylsulfonamido)hippuric acid, and 4-
(phenylsulfonamidomethyl)benzoic acid respectively.
Example 19
Modification of Amino Acids with Benzene Sulfonyl Chloride
A mixture of sixteen amino acids are prepared prior to chemical modification.
The constituents of the mixture are summarized in the Table below. 65 grams of the
amino acid mixture (total concentration of [--NH2] groups=0.61 moles) is dissolved in
760 mL of 1N sodium hydroxide solution (0.7625 equivalents) at room temperature.
After stirring for 20 minutes, benzene sulfonyl chloride (78 ml, 1 eq.) is added over a 20
minute period. The reaction mixture is then stirred for 2.5 hours, without heating. As
some precipitation may occur, additional NaOH solution (2N) may be added to the
solution until it reaches pH 9.3. The reaction mixture is stirred overnight at room
temperature. Thereafter, the mixture is acidified using dilute hydrochloric acid (38%, 1:4)
and a cream colored material precipitates out. The resulting precipitate is isolated by
decantation and dissolved in sodium hydroxide (2N). This solution is then reduced in
vacuo to give a yellow solid, which is dried on the lyophilizer.
Example 20
Modification of a Mixture of Five Amino Acids Using Benzene Sulfonyl Chloride
An 86.1 g (0.85 moles of NH2) mixture of amino acids (see Table below) is
dissolved in 643 mL (1.5 eq.) of aqueous 2N sodium hydroxide solution. After stirring
for 30 minutes at room temperature, benzene sulfonyl chloride (108 mL, 0.86 moles) is
added portionwise into the amino acid solution over a 15 minute period. After stirring for
2.5 hours at room temperature, the pH of the reaction mixture (pH 5) is adjusted to pH 9
with additional 2N sodium hydroxide solution. The reaction mixture is stirred overnight
at room temperature. Thereafter, the pH of the reaction mixture is adjusted to pH 2.5 by
addition of dilute aqueous hydrochloric acid solution (4:1, H2O: HC1) and a precipitate of
modified amino acids is formed. The upper layer is discarded and the resulting yellow
precipitate is isolated by decantation, washed with water and dissolved in 2N sodium
hydroxide (2N). The solution is reduced in vacuo to give a yellow solid, which is
lyophilized overnight.
An 86 g (0.85 moles of NH2) mixture of amino acids (see Table in Example 20) is
dissolved in 637 mL (1.5 eq.) of aqueous 2N sodium hydroxide solution. After stirring
for 10 minutes at room temperature, benzoyl chloride (99 mL, 0.85 moles) is added
portionwise into the amino acid solution over a 10 minute period. After stirring for 2.5
hours at room temperature, the pH of the reaction mixture (pH 12) is adjusted to pH 2.5
using dilute hydrochloric acid (4:1, H2O: HC1) and a precipitate of modified amino acids
is formed. After settling for 1 hour, the resulting precipitate is isolated by decantation,
washed with water and dissolved in sodium hydroxide (2N). This solution is then reduced
in vacuo to give crude modified amino acids as a white solid ( expected yield 220.5 g).
Example 22
Modification of L-valine Using Benzene Sulfonyl Chloride
L-Valine (50 g, 0.43 mol) is dissolved in 376 mL (0.75 eq.) of aqueous 2N
sodium hydroxide by stirring at room temperature for 10 minutes. Benzene sulfonyl
chloride (68.7 mL, 0.38 mol, 1.25 eq.) is then added to the amino acid solution over a 20
minute period at room temperature. After stirring for 2 hours at room temperature, a
precipitate appears. The precipitate is dissolved by adding 200 mL of additional 2N
sodium hydroxide solution. After stirring for an additional 30 minutes, dilute aqueous
hydrochloric acid solution (4:1, H2O: HC1) is added until the pH of the reaction mixture
reaches 2.6. A precipitate of modified amino acids formed and is recovered by
decantation. This material is dissolved in 2N sodium hydroxide and dried in vacuo co to
give a white solid. Expected yield of crude modified amino acids is 84.6 g, 77%).
Example 23
Modification of Phenylalanine Methyl Ester Using Hippuryl Chloride
L-Phenylalanine Methyl Ester Hydrochloride (15 g, 0.084 mole) is dissolved in
dimethylformamide (DMF) (100 mL) and to this is added pyridine (30 mL). A solution of
hippuryl chloride (16.6 g, 0084 moles in 100 mL DMF) is immediately added to the
amino acid ester solution in two portions. The reaction mixture is stirred at room
temperature overnight. The reaction mixture is then reduced in vacuo and dissolved in 1N
aqueous sodium hydroxide. The solution is heated at 70° C. for 3 hours in order to
hydrolyze the methyl ester to a free carboxyl group. Thereafter, the solution is acidified
to pH 2.25 using dilute aqueous hydrochloric acid solution (1:3 HC1/H2O). A gum-like
precipitate is formed and this is recovered and dissolved in 1N sodium hydroxide. The
solution is reduced in vacuo to afford an expected 18.6 g of crude modified amino acid
product. After recrystallization from acetonitrile, pure modified phenylalanine (expected
yield 12 g) is recovered as a white powder. m.p. 223-225° C.
Example 24
Preparation of Dosing Solutions of PYY(3-36)
In a test tube 568 mg of acetyl phenylalanine aldehyde, 132 mg of carbomethoxy
phenylalanylleucine and 100 mg acetyl-Phe-Leu-Leu-Arg aldehyde are added to 2.9 ml
of 15% ethanol. The solution is stirred and NaOH (1.0 N) is added to raise the pH to 7.2.
Water is added to bring the total volume to 4.0 mL. The sample had a carrier
concentration of 200 mg/mL. PYY(3-36) (800 mg) is added to the solution. The total
PYY3-36 concentration is 200 mg/mL.
Following a similar procedure a second solution having 668 mg of acetyl
phenylalanine aldehyde and 132 mg of carbomethoxy phenylalanylleucine as the carrier
composition and a third solution having as the carrier acetyl phenylalanine aldehyde are
prepared. Each solution had an endotoxin-free PYY(3-36) concentration of 200 µg/mL.
Example 25
Preparation of Modified Amino Acid/PYY(3-36) Compositions
Preparation of Modified Amino Acid Microspheres Containing Encapsulatedendotoxin-
free PYY3-36
The modified amino acid mixture, prepared in accordance with Example 9, is
dissolved at 40° C. in distilled water (pH 7.2) at a concentration of 100 mg/ml. The
solution is then filtered with a 0.2 micron filter and the temperature is maintained at 40°
C. PYY3-36 (Bachem) is dissolved in an aqueous solution of citric acid (1.7N) and
gelatin (5%) at a concentration of 150 mg/ml. This solution is then heated to 40 C.
The two heated solutions are then mixed 1:1 (v/v). The resulting microsphere suspension
is then filtered with glass wool and centrifuged for 50 minutes at 1000 g. The pellet is
resuspended with 0.85N citric acid to a volume 5 to 7 fold less than the oriGlnal volume.
PYY3-36 concentration of the resuspended pellet is determined by HPLC. Additional
microspheres are made according to the above procedure without PYY3-36. These
"empty microspheres" are used to dilute the encapsulated salmon PYY3-36 microsphere
preparation to a final dosing suspension, if needed.
(b) Preparation of a Soluble Modified Amino Acid Carrier/PYY3-36 System
A soluble amino acid dosing preparation containing PYY3-36 is prepared by
dissolving the modified amino acid material in distilled water (pH 8) to an appropriate
concentration. The solution is heated to 40° C. and then filtered with a 0.2 micron filter.
PYY3-36, also dissolved in distilled water, is then added to the modified amino acid
solution prior to oral administration.
Pulmonary Delivery of PYY3-36
(Prophetic)
The carrier compounds, prepared as described below may be used directly as a delivery
carrier by simply mixing one or more compound or salt, poly amino acid or peptide with
an endotoxin-free Y2 receptor-binding peptide for pulmonary delivery.
The administration mixtures are prepared by mixing an aqueous solution of the
carrier with an aqueous solution of the active ingredient, just prior to administration.
Alternatively, the carrier and the biologically or chemically active ingredient can be
admixed during the manufacturing process. The solutions may optionally contain
additives such as phosphate buffer salts, citric acid, acetic acid, gelatin, and gum acacia.
A number of known pulmonary delivery methods can use endotoxin-free Y2 receptor-
binding peptides, especially PYY3-36, to improve the delivery of PYY to the lungs. The
following non-limiting patent applications are incorporated herein by reference for
pulmonary delivery: US Patent application 20030223939, 20030215514, 20030215512,
20030209243, 20030203036, 20030198601, 20030183228, 200301885765,
20030150454, 20030124193, 20030094173.
EXAMPLE 26
Preparation of Carriers
Preparation of 2-(4-(N-salicyloyl)aminophenyl) propionic acid (Carrier B)
A slurry of 58.6 g (0.355 mol) of 2-(4-aminophenyl)propionic acid and 500 ml of
methylene chloride is treated with 90.11 ml (77.13 g. 0-710 mol) of trimethylsilyl
chloride and is heated to reflux for 120 min. The reaction mixture is cooled to 0°C. and
treated with 184.44 ml (107.77 g, 1.065 mol) of triethylamine. After stirring for 5
minutes, this mixture is treated with a solution of 70.45 g (0.355 mol) of O-
acetylsalicyloyl chloride and 150 ml of methylene chloride. The reaction mixture is
wanned to 25° C. and stirred for 64 hr. The volatiles are removed in vacuo. The residue is
stirred in 2N aqueous sodium hydroxide for one hour and acidified with 2 M aqueous
sulfuric acid. The solid is recrystallized twice from ethanol/water to give a tan solid.
Isolation by filtration results in an expected yield of 53.05 g (52% yield) of 2-(4-(N-
salicyloyl)aminophenyl)propionic acid. Properties. Solubility: 200 mg/m: 200 mg+350
.mL 2N NaOH+650 .mL H2O-pH-7.67. Analysis: C, 67.36; H, 5.3; N, 4.91. .
Preparation of Sodium 2-(4-(N-salicyloyl)aminophenyl)propionate (Sodium Salt of
Carrier B)
A solution of 53.05 g (0.186 mol) of 2-(4-(N-salicyloyl)aminophenyl- )propionic
acid and 300 ml of ethanol is treated with 7.59 g (0.190 mol) of NaOH dissolved in 22 ml
of water. The reaction mixture is stirred for 30 min at 25°C and for 30 min at 0° C. The
resulting pale yellow solid is isolated by filtration to give 52.61 g of sodium 2-(4-(N-
salicyloyl)aminophenyl)propionate. Properties. Solubility: 200 mg/ml clear solution,
pH=6.85. Analysis C, 60.45; H, 5.45; N, 3.92; Na, 6.43. Melting point 236-238.degree.
C.
Preparation of the Sodium Salt of Carrier C
A 2L round bottom flask equipped with a magnetic stirrer and a reflux condenser
is charged with a suspension of 3-(4-aminophenyl)propio- nic acid (15.0 g. 0.084 moles.
1.0 equiv.) in dichloromethane (250 ml). Chlorotrimethylsilane (18.19 g, 0.856 moles,
2.0 equiv.) is added in one portion, and the mixture is heated to reflux for 1.5 h under
argon. The reaction is allowed to cool to room temperature and is placed in an ice bath
(internal temperature containing triethylamine (25.41 g., 0.251 moles, 3.0 equiv.). The triethylamine is added
dropwise over 15 min, and a yellow solid forms during the addition. The funnel is
replaced by another addition funnel containing a solution of 2,3-dimethoxybenzoylchlo-
ride (I 8.31 g, 0.091 moles, 1.09 equiv.) in dichloromethane (100 mL). The solution is
added dropwise over 30 run. The reaction is stirred in the ice bath for another 30 min and
at ambient temperature for 3 h. The dicholoromethane is evaporated in vacuo to give a
brown oil. The brown oil is cooled in an ice bath, and an ice-cold solution of saturated
sodium bicarbonate (250 ml) is added. The ice bath is removed, and the reaction is stirred
1 h to afford a clear brown solution. The solution is acidified with concentrated HC1 and
stored at ca SC for 1 hour. The mixture is extracted with dichloromethane (3 .times. 100
mL), dried over sodium sulfate, the salts filtered off and the dichloromethane removed in
vacuo. The resulting solid is recrystallized from 50% ethyl acetate/water (v/v) to afford
Carrier C acid as off white needles (25.92 g. 90%). Analysis for C19H21NO5: C, 66.46; H,
6.16; N, 4.08. mp=99-102°C.
12 grams of the Carrier C acid is dissolved in ethanol, 75 mL, with wanning. To
this solution a 8.5 M Sodium hydroxide (1.02 molar equivalents, 1.426 grams in 4.5 mL
water) solution is added. The mixture is stirred for 15 minutes. Approximately three
quarters of the ethanol is remove in vacuo and n-heptane, 100 mL, is added to the
resulting oil causing a precipitate to form. The solids are dried in vacuo at 50° C.
Analysis: C19H20NO5Na0.067H2O: C, 62.25; H, 5.54; N, 3.82; Na, 6.27.
Preparation of N-(4-methvlsalicvloyO-8-aminocaprylic acid (Carrier D)
(a) Preparation of Oligo(4-methylsalicylate)
Acetic anhydride (32 mL, 34.5 g, 0.338 mol, 1.03 eq), 4-methylsalicylic acid (50
g, 0.329 mmol, 1.00 eq), and xylenes (100 mL) are added to a 1 L, four-neck flask fitted
with a magnetic stir bar, a thermometer, and a condenser. The flask is placed in a sand
bath and heating of the cloudy white mixture begun. The reaction mixture clears to a
yellow solution around 90° C. Most of the volatile organics (xylenes and acetic acid) are
distilled into the Dean-Stark trap over three hours (135-146° C). Distillation is continued
for another hour (a total of 110 mL distilled), during which the pot temperature slowly
rises to 204° C. and the distillate slows to a trickle. The residue is poured off while still
hot into an aluminum tray. Upon cooling a brittle yellow glass forms. The solid is ground
to a fine powder. The oligo(4-methylsalicylate) received is used without further
purification.
(b) Preparation of N-(4-methylsalicyloyl)-8-aminocaprylic acid
A 7M solution of potassium carbonate (45 mL, 43.2 g, 0.313 mol, 0.95 eq), 8-
aminocaprylic acid (41.8 g, 262 mol, 798 eq), and water (20 mL) are added to a 1 L
round bottom flask equipped with a magnetic stir bar, condenser, and an addition fuel.
The white cloudy mixture is treated with a solution of oligo(4-methylsalicylate) (44.7 g,
0.329 mmol 1.0 eq) and dioxane (250 mL), added over thirty minutes. The reaction
mixture is heated to 90°C. for 3 hours (at which time the reaction is determined to have
finished, by HPLC). The clear orange reaction mixture is cooled to 30°C. and acidified to
pH=2 with 50% aqueous sulfuric acid (64 g). The resulting solid is isolated by filtration.
The white solid is recrystallized from 1170 mL of 50% ethanol-water. The solid is
recovered by filtration and is dried over 18 hours in a 50°C. vacuum oven. The N-(4-
methylsalicyloyl)-8-ami- nocaprylic acid is isolated as a white solid (30.88 g, 52%);
mp=113-114°. Analysis: C6H23NO4: C, 65.51; H, 7.90; N, 4.77.
An aqueous solution of PYY(3-36) is then prepared and mixed with one or more
of the carrier to produce a PYY(3-36) composition, which then can be sprayed into the
lungs. A suitable concentration of PYY3-36 for the resultant composition should be
about 400 mg/mL. See U.S. Patent Application No. 20030072740.
Example 27
Total Extraction Radioimmunoassay for the Determination of the concentration of
PYY in Plasma
1.0 Introduction:
A radioimmunoassay was developed to measure the concentration of
Human Peptide YY(3-36) (hPYY) in human plasma. Samples are collected with
anticoagulant (EDTA) and protease inhibitor (aprotinin) and frozen. The assay is a
four day process. Samples, controls, and standards are extracted in alcohol and dried
on Day 1. All samples are reconstituted and mixed with a polyclonal rabbit antiserum
directed against hPYY on Day 2. Iodinated hPYY is added on Day 3. Specific
precipitating agents (Goat anti-Rabbit IgG and Normal Rabbit Serum) are added on
Day 4. Bound tracer is separated from free tracer by centrifugation, and the bound
tracer is counted in the gamma counter. Concentration is calculated by interpolation
of a standard curve and assay performance is controlled with Quality Control
samples.
2.0 Materials:
2.1 Peninsula PYY kit (Peninsula Laboratories, Cat. No. S-2043-0001)
2.2 Reagent Alcohol (Fisher Inc., Cat. No. A995-4) (or equivalent)
2.3 Stripped human plasma (with Lithium Heparin, fasted, pooled) Golden
West Biologics Inc. (Cat. No., SD1020-H) (Analytical SOP # A-003)
2.4 Ice Baths (Fisher, Cat No. 11-676-36) (or equivalent)
2.5 Disposable 10 mL pipets (Fisher Cat. No. 13-678-1 1E) (or equivalent)
2.6 Standard Synthetic Human PYY from Nastech QC (3-36) (Bachem Cat.
No. H8585)
2.7 Distilled Water (Milli-Q Millipore, Cat. No. ZMQ56VFT1) (or
equivalent)
2.8 Triton X-l00 (Sigma, Cat. No. T-9284) (or equivalent)
2.9 Aluminum Foil (Fisher, Cat. No. 01-213-3) (or equivalent)
2.10 Aprotinin (ICN Biomedicals Inc. Cat. No. 190779) (or equivalent)
2.11 12x75 mm tubes (Evergreen Scientific, Cat. No. 214-2023-010) (or
equivalent)
2.12 12x75 mm tube caps (Evergreen Scientific, Cat. No. 300-2912-G20) (or
equivalent)
2.13 1.5 mL microfuge tubes (Fisher, Cat. No. 05-402-25) (or equivalent)
2.14
3.0 Instruments:
3.1 Wallac WIZARD 1470 Automatic Gamma Counter (Perkin Elmer, Model
No. 1470-002) (or equivalent)
3.2 Isotemp Basic Freezer, -70°C (Kendro Laboratory Products, Model No.
C90-3A31) (or equivalent)
3.3 CentriVap Concentrator (Labconco, Cat. No. 7810000) (or equivalent)
3.4 VX-2500 Multi-tube Vortexer (VWR, Cat. No. 58816-115) (or
equivalent)
3.5 Marathon 21000R Centrifuge (Fisher, Cat. No. 04-977-21000R) (or
equivalent)
3.6 SwinGlng bucket rotor (Fisher, Cat. No. 04-976-006) (or equivalent)
3.7 Motorized pipet-aid (Fisher, Cat. No. 13-68 ] -15E) (or equivalent)
3.8 EppendorfMicropipette
3.8.1 2 mL - 20 mL (Fisher, Cat. No. 21-371-6) (or equivalent)
3.8.2 20 mL - 200 mL (Fisher, Cat. No. 21-371-10) (or equivalent)
3.8.3 100 mL -1000 mL (Fisher, Cat. No. 21-371-13) (or equivalent)
3.9 Eppendorf Repeating Pipettor (Fisher, Cat. No. 21-380-9) (or equivalent)
3.10 Eppendorf Repeating Pipettor Combi-tips
3.10.1 2.5 mL (Fisher, Cat. No. 21-381-331) (or equivalent)
3.10.2 25 mL (Fisher, Cat. No. 21-381-115) (or equivalent)
3.11 Positive displacement pipet (Fisher, Cat. No. 21-169-10A) (or equivalent)
4.0 Procedure
DAY1
4.1 Thaw necessary reagents and samples for the assay. Prepare RIA buffer to
IX concentration (RIAB) if sufficient amount is not available.
4.2 Prepare standard curve samples in pooled stripped human plasma. Prepare as
follows if using a starting concentration of 12.8 mg/mL.
4.2.1 Add 990 mL RIAB to tube O.
4.2.2 Add 990 mL pooled plasma to tube A.
4.2.3 Add 500mL pooled plasma to tubes B-H.
4.2.4 Add 10 mL 12.8 mg/mL Standard to tube O. Vortex.
4.2.5 Add 10 mL solution from tube O to tube A. Vortex.
4.2.6 Add 500 mL solution from tube A to tube B. Vortex.
4.2.7 Add 500mL solution from tube B to tube C. Vortex.
4.2.8 Repeat dilutions as in 4.2.7 through tube H. (See Diagram #1)
4.3 Dilute unknown human plasma samples to be tested if necessary. Samples
should be diluted in pooled stripped human plasma.
4.4 Add 1.2 mL of cold alcohol to empty tubes for NSB, TB, all Standards, QC
samples, and human plasma samples to be tested.
4.5 Add 400 uL of pooled stripped human plasma to NSB and TB tubes. Cap,
Vortex.
4.6 Add 400µL of each prepared Standard sample from 4.2.5 to 4.2.8 to
respective standard curve tubes H-A (See Diagram #1). Cap, Vortex.
4.7 Add 400 µL of QC samples to respective tubes. Cap, Vortex.
4.8 Add 400 µL of each sample to be tested its respective tube. Cap, Vortex.
4.9 Incubate all samples on ice for 30-60 minutes.
4.10 Turn on the cold-trap switch on the Concentrator.
4.11 Centrifuge all tubes at 3000 rpm, 4°C for 15 minutes.
4.12 Transfer 1.3 mL of supernatant from each sample to a new set of empty
tubes. Store in an ice bath or at 2-8°C if not spun immediately.
4.13 Place samples in the Concentrator.
4.14 Samples should spin for two hours at 40°C, then at ambient temperature
for a total of 5 hours or until dry.
4.15 Remove dried samples, cover and store overnight at 2-8°C.
DAY 2
4.16 Remove the dried tubes from the 2-8°C cooler.
4.17 Add 100 µL of 4x RIA buffer concentrate to each tube.
4.18 Add 100 µL of 0.6% TX100 to each tube. (Attachment #1) Vortex for a
minimum of 30 seconds to ensure all extracts are fully reconstituted.
4.19 Incubate all samples on ice for 30-60 minutes.
4.20 Add 200 µL of distilled water to each tube. Vortex.
4.21 Transfer 100 µL of each sample extract to respective tube.
Note: NSB, TB, TC, Standard Curve samples, and QCs are
typically run in triplicate, requiring three tubes per sample.
Human plasma samples many be tested in any variation (up
to three replicates) depending on sample availability.
4.22 Prepare Rabbit anti-PYY as described in the Peninsula Laboratories kit
insert.
4.23 Add 100 µL RIAB to each NSB tube.
4.24 Add 200 µL RIAB to each TC tube.
4.25 Add 100 µL Rabbit anti-PYY to all remaining tubes. Vortex.
4.26 Cover with foil and store overnight at 2-8°C.
DAY 3
4.27 Remove the tubes from the 2-8°C cooler.
4.28 Prepare l25I-Peptide YY tracer (Attachment #2).
4.29 Add 100 µL of prepared tracer to all tubes. Cap and vortex.
4.30 Store overnight at 2-8°C.
DAY 4
4.31 Remove the tubes from the 2-8°C cooler.
4.32 Prepare Goat anti-Rabbit IgG serum (GARGG) and Normal Rabbit Serum
(NRS) as described in the Peninsula Laboratories kit insert.
4.33 Add 100 µL GARGG to each tube (except TC tubes).
4.34 Add 100 µL NRS to each tube (except TC tubes). Vortex.
4.35 Incubate 90-120 minutes at room temperature.
4.36 Add 500 µL RIAB to tubes to be centrifuged immediately (except TC
tubes). Vortex.
Note: 500 µL RIAB should be added to tubes just prior to
centrifugation. Only add RIAB to the number of tubes that
are ready to be centrifuged. 500 µL RIAB should be added
to additional tubes when they are ready to be centrifuged.
4.37 Centrifuge tubes (containing 500 µL RIAB) at 3000 rpm at 4°C, for 15
minutes. Do not centrifuge TC tubes.
4.38 Aspirate supernatant from centrifuged tubes.
4.39 Place tubes in designated black racks for counting on the Gamma counter.
The first rack should have the appropriate Program number attached. All
racks that follow should contain no program number. Samples should be
added in the following order:
4.39.1 NSB tubes
4.39.2 TB tubes
4.39.3 TC tubes
4.39.4 Standard tubes (increasing concentration)
4.39.5 QC samples (3 concentrations)
4.39.6 Unknown human samples
4.39.7 QC samples (3 concentrations)
4.40 Place an empty black rack with the Stop label attached after all samples to
be counted.
4.41 Press 'Start' on the Gamma Counter keypad to start counting.
4.42 Press 'E' for enter on the Gamma Counter keypad to display CPM results.
5.0 Evaluation of Results
5.1 The following guidelines are applied to the identification and rejection of
outliers in the assay. In order for a result to qualify as an outlier and not
be included in the final calculation of results, all of the following
conditions must be met.
5.1.1 QCs and unknown samples:
5.1.1.1 %CV of all replicates must be great than 20%.
5.1.1.2 There must be at least three results to evaluate.
5.1.1.3 The difference between the suspected outlier and the result
next closest in value must be greater than 20%.
5.1.1.4 The difference between the high and low remaining results
must be less than 20%.
5.1.2 Standard Curve samples:
5.1.2.1 %CV of all replicates much be greater than 15%.
5.1.2.2 There must be at least three results to evaluate.
5.1.2.3 The difference between the suspected outlier and the result
next closest in value must be greater than 15%.
5.1.2.4 The difference between the high and low remaining results
must be less than 15%.
6.0 Assay Specifications
6.1 QC samples are prepared at the following concentrations. Two QC
samples at each concentration are tested in an assay. Four of the six QC
samples tested must be within the following ranges (±30% of nominal
concentration). At least one of the two QCs tested at any concentration
must be within range of the assay for data to be acceptable.
6.1.1 QC1 (100pg/mL) 70-130 pg/mL
6.1.2 QC2 (200 pg/mL) 140-260 pg/mL
6.1.3 QC3 (500 pg/mL) 350-650 pg/mL
6.2 Standard curve parameter requirements TBD.
Example 28
Preparation of an NPY Formulation Free of a Stabilizer that is a Protein
A PYY formulation suitable for intranasal administration of NPY, which is
substantially free of a stabilizer that is a protein is prepared having the formulation
listed below.
12. About 3/4 of the water is added to a beaker and stirred with a stir bar on a
stir plate and the sodium citrate is added until it is completely dissolved.
13. The EDTA is then added and stirred until it is completely dissolved.
14. The citric acid is then added and stirred until it is completely dissolved.
15. The methyl-ß-cyclodextrin is added and stirred until it is completely
dissolved.
16. The DDPC is then added and stirred until it is completely dissolved.
17. The lactose is then added and stirred until it is completely dissolved.
18. The sorbitol is then added and stirred until it is completely dissolved.
19. The chlorobutanol is then added and stirred until it is completely
dissolved.
20. The NPY(3-36) is added and stirred gently until it dissolved.
21.11 Check the pH to make sure it is 5.0 ± 0.25. Add dilute HC1 or dilute
NaOH to adjust the pH.
22. Add water to final volume.
A PYY formulation suitable for intranasal administration of PP, which is
substantially free of a stabilizer that is a protein is prepared having the formulation
listed below.
23. About 3/4 of the water is added to a beaker and stirred with a stir bar on a
stir plate and the sodium citrate is added until it is completely dissolved.
24. The EDTA is then added and stirred until it is completely dissolved.
25. The citric acid is then added and stirred until it is completely dissolved.
26. The methyl-ß-cyclodextrin is added and stirred until it is completely
dissolved.
27. The DDPC is then added and stirred until it is completely dissolved.
28. The lactose is then added and stirred until it is completely dissolved.
29. The sorbitol is then added and stirred until it is completely dissolved.
30. The chlorobutanol is then added and stirred until it is completely
dissolved.
31. The PP(3-36) is added and stirred gently until it dissolved.
32. 11 Check the pH to make sure it is 5.0 ± 0.25. Add dilute HC1 or dilute
NaOH to adjust the pH.
33. Add water to final volume.
Formulation pH 5 +/- 0.25
Although the foregoing invention has been described in detail by way of
example for purposes of clarity of understanding, it will be apparent to the artisan that
certain changes and modifications are comprehended by the disclosure and may be
practiced without undue experimentation within the scope of the appended claims,
which are presented by way of illustration not limitation.
149
WE CLAIM:
1. A transmucosal Y2 receptor-binding peptide formulation such as herein
described capable of raising the concentration of the Y2 receptor-binding
peptide in the plasma of a mammal by at least 5 pmole per liter of plasma or
more when a dose containing at least 50 µg of the Y2 receptor-binding agonist
is administered transmucosally to said mammal.
2. The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
1, wherein the Y2 receptor-binding peptide is selected from the group
consisting of peptide YY (PYY), neuropeptide Y (NPY) and pancreatic
peptide (PP).
3. The transmucosal Y2 receptor-binding peptide formulation as claimed in
claims 1 and 2 comprising of at least one mucosal delivery-enhancing agent
selected from the group consisting of:
a. a solubilization agent such as herein described;
b. a charge-modifying agent such as herein described;
c. a pH control agent such as herein described;
d. a degradative enzyme inhibitory agent such as herein described;
e. a mucolytic or mucus clearing agent such as herein described;
f. a ciliostatic agent such as herein described;
g. a membrane penetration-enhancing agent selected from (i) a surfactant,
(ii) a bile salt, (iii) a phospholipid additive, mixed micelle, liposome,
or carrier, (iv) an alcohol, (v) an enamine, (vi) a NO donor compound,
(vii) a long-chain amphipathic molecule (viii) a small hydrophobic
penetration enhancer; (ix) sodium or a salicylic acid derivative; (x) a
glycerol ester of acetoacetic acid (xi) a cyclodextrin or beta-
cyclodextrin derivative, (xii) a medium-chain fatty acid, (xiii) a
chelating agent, (xiv) an amino acid or salt thereof, (xv) an N-
acetylamino acid or salt thereof, (xvi) an enzyme degradative to a
selected membrane component, (xvii) an inhibitor of fatty acid
synthesis, or (xviii) an inhibitor of cholesterol synthesis; or (xix) any
combination of the membrane penetration enhancing agents recited in
(i)-(xix);
h. a modulatory agent of epithelial junction physiology;
i. a vasodilator agent;
j. a selective transport-enhancing agent; and
k. a stabilizing delivery vehicle, carrier, support or complex-forming
species.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
I wherein the formulation is an intranasal formulation.
The transmucosal Y2 receptor-binding peptide formulation as claimed in
claims 1-4 wherein the formulation is comprised of at least two polyols.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
5 wherein the polyols are lactose and sorbitol.
The transmucosal Y2 receptor-binding peptide formulation as claimed in
claims 1-6 comprised of a chelating agent.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
7 wherein the chelating agent is ethylenediamine tetraacetic acid (EDTA).
The transmucosal Y2 receptor-binding peptide formulation as claimed in
claims 1-8 comprised of a solubilizing agent.
The transmucosal Y2 receptor-binding peptide formulation as claimed in
claim9, wherein the solubilizing agent is a cyclodextrin.
The transmucosal Y2 receptor-binding peptide formulation as claimed in
claims 1-10, comprising a surfactant.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
I1 wherein the surfactant is L-a-phosphatidylcholine didecanoyl (DDPC).
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
1 wherein the Y2 receptor-binding peptide is PYY3-36.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
12 wherein the formulation is optionally comprised of water.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
13 wherein the formulation has a pH of 3 to 6.
The transmucosal Y2 receptor-binding peptide formulation as claimed in claim
14 wherein the pH is 5.0± 0.3.
A peptide YY (PYY) composition comprised of a solubilizing agent, a
chelating agent, a polyol and a PYY peptide wherein the PYY peptide is
comprised of an amino acid sequence selected from the group consisting of
SEQ ID NOs: 2, 3 and SEQ ID NOs: 90-105.
The PYY composition as claimed in claim 17 wherein the PYY composition is
comprised of at least two polyols.
The PYY composition as claimed in claim 17 wherein the polyols are selected
from the group consisting of sucrose, mannitol, sorbitol, lactose, L-arabinose,
D-erythrose, D-ribose, D-xylose, D-mannose, trehalose, D-galactose,
lactulose, cellobiose, gentibiose, glycerin and polyethylene glycol.
The PYY composition as claimed in claim 18 wherein the polyols are lactose
and sorbitol.
The PYY compostion as claimed in claim 18 wherein the chelating agent is
ethylene diamine tetraacetic acid (EDTA) or ethylene glycol tetraacetic acid
(EGTA).
The PYY composition as claimed in claim 21 wherein the chelating agent is
EDTA.
The PYY composition as claimed in claim 16 wherein the solubilizing agent is
selected from the group consisting of a cyclodextran, hydroxypropyl-ß-
cyclodextran, sulfobutylether-ß-cyclodextran and methyl-ß-cyclodextrin.
The PYY composition as claimed in claim 22 wherein the solubilizing agent is
a cyclodextrin.
The PYY composition as claimed in claim 16 wherein the composition
optionally comprises a surface-active agent.
The PYY composition as claimed in claim 24 wherein the surface-active agent
is selected from the group consisting of nonionic polyoxyethylene ether, bile
salts such, sodium glycocholate (SGC), deoxycholate (DOC), derivatives of
fusidic acid, sodium taurodihydrofusidate (STDHF), L-a-phosphatidylcholine
didecanoyl (DDPC), polysorbate 80 and polysorbate 20, a polyethylene glycol
(PEG), cetyl alcohol, polyvinylpyrolidone (PVP), a polyvinyl alcohol (PVA),
lanolin alcohol, and sorbitan monooleate.
The PYY composition as claimed in claim 25 wherein the surface-active agent
is DDPC.
The PYY composition as claimed in claim 16 wherein the composition is an
aqueous PYY composition optionally comprised of water.
The PYY composition as claimed in claim 27 wherein pH of the aqueous PYY
composition is from 3 to 6.
The PYY composition as claimed in claim 29 wherein the pH of the aqueous
PYY composition is 5.0± 0.3.
The PYY composition as claimed in claim 16 wherein the PYY peptide is
comprised of PYY(3-36) (SEQ ID NO: 2).
A PYY composition comprised of methyl-ß-cyclodextrin, EDTA, lactose,
sorbitol, DDPC and a PYY peptide wherein the PYY peptide is comprised of
an amino acid sequence selected from the group consisting of SEQ ID NOs: 2,
3 and SEQ ID NOs: 90-105.
The PYY composition as claimed in claim 31 wherein the PYY peptide is
comprised of PYY(3-36) (SEQ ID NO: 2).
An aqueous PYY(3-36) formulation capable of raising the concentration of the
PYY(3-36) in the plasma of a patient by at least 5 pmole per liter of plasma
when a dose containing at least 50 µg of PYY(3-36) is administered
transmucosally to said mammal.
The PYY(3-36) formulation as claimed in claim 34, wherein about 50 to about
200 µL of the formulation is administered intranasally to said patient.
An aqueous PYY(3-36) formulation comprising PYY(3-36) and a solubilizing
agent wherein the formulation is substantially free of a stabilizer that is a
polypeptide or a protein.
The PYY(3-36) formulation as claimed in claim35, comprising a chelating
agent, one or more polyols, and a pH 3.0 to pH 6.5.
The PYY(3-36) formulation as claimed in claim 36, comprising a surface-
active agent.
The PYY(3-36) formulation as claimed in claim 37, wherein the formulation is
pH 5.0.
The PYY(3-36) formulation as claimed in claim 37, wherein the formulation is
endotoxin-free.
The PYY(3-36) formulation as claimed in claim 36, wherein the formulation is
comprised of at least two polyols.
The PYY(3-36) formulation as claimed in claim 40, wherein the polyols are
selected from the group consisting of sucrose, mannitol, sorbitol, lactose, L-
arabinose, D-erythrose, D-ribose, D-xylose, D-mannose, trehalose, D-
galactose, lactulose, cellobiose, gentibiose, glycerin and polyethylene glycol.
The PYY(3-36) formulation as claimed in claim 41, wherein the polyols are
lactose and sorbitol.
The PYY(3-36) formulation as claimed in claim 36, wherein the chelating
agent is ethylenediamine tetraacetic acid (EDTA) or ethylene glycol tetraacetic
acid (EGTA).
The PYY(3-36) formulation as claimed in claim 44, wherein the chelating
agent is EDTA.
The PYY(3-36) formulation as claimed in claim 36, wherein the solubilizing
agent is selected from the group consisting of a cyclodextran, hydroxypropyl-
P-cyclodextran, sulfobutylether-ß-cyclodextran and methyl-|3-cyclodextrin.
The PYY(3-36) formulation as claimed in claim 45, wherein the solubilizing
agent is a cyclodextrin.
The PYY(3-36) formulation as claimed in claim 36, wherein the surface-active
agent is selected from the group consisting of nonionic polyoxyethylene ether,
bile salts such, sodium glycocholate (SGC), deoxycholate (DOC), derivatives
of fusidic acid, sodium taurodihydrofusidate (STDHF), L-a-
phosphatidylcholine didecanoyl (DDPC), polysorbate 80 and polysorbate 20, a
polyethylene glycol (PEG), cetyl alcohol, polyvinylpyrolidone (PVP), a
polyvinyl alcohol (PVA), lanolin alcohol, and sorbitan monooleate.
The PYY(3-36) formulation as claimed in claim 47, wherein the surface-active
agent is DDPC.
The PYY(3-36) formulation as claimed in claim 36, wherein the formulation is
comprised of a preservative selected from the group consisting of
chlorobutanol and benzalkonium chloride.
The PYY(3-36) formulation as claimed in claim 49, wherein the preservative
is chlorobutanol.
The PYY(3-36) formulation as claimed in claim 47 or 49, wherein 50 to 200 µL of the formulation is administered intranasally.
The PYY(3-36) formulation as claimed in claim 36, wherein following
mucosal administration of said formulation a time to maximum plasma
concentration, Tmax, of said peptide is less than 30 minutes.
The PYY(3-36) formulation as claimed in claim 53, wherein Tmax is 20
minutes.
The PYY(3-36) formulation as claimed in claim 53, wherein mucosal
administration of said formulation raises plasma concentrations of said peptide
has an elimination half life of 55 minutes.
A PYY(3-36) formulation in the manufacture of a medicament for treating
obesity in mammals, wherein a Cmax greater than 300 pg/ml results from a
single mucosal administration of said medicament.
The PYY(3-36) formulation as claimed in claim 56, wherein the Cmax is greater
than 75 pmole/1.
The PYY(3-36) formulation as claimed in claim 56, wherein exposure of a
mucosal epithelial cell layer to said formulation decreases electrical resistance
across said layer by at least 100-fold.
The PYY(3-36) formulation as claimed in claim 58, wherein said mucosal
epithelial cell layer is a monolayer of bronchial cells.
The PYY(3-36) formulation as claimed in claim 56, wherein exposure of a
mucosal epithelial cell layer to said formulation increases permeation of the
peptide across said layer at least 30-fold over simple buffer solutions.
The PYY(3-36) formulation as claimed in claim 60, wherein permeation of the
peptide across said layer at least 100-fold over simple buffer solutions.
The PYY(3-36) formulation as claimed in claim 61, wherein said mucosal
epithelial cell layer is a monolayer of bronchial cells.
The PYY(3-36) formulation as claimed in claim 56, wherein the stability of
the peptide in the formulation is at least 96% over one month at either 5 °C or
25 °C.
A peptide YY (PYY) composition comprised of a PYY peptide, and a
stabilizer other than a polypeptide or protein, wherein the PYY peptide is
comprised of an amino acid sequence selected from the group consisting of
SEQ ID NOs: 2, 3 and SEQ ID NOs: 90-105.
A PYY(3-36) formulation comprised of water, a Y2 receptor-binding peptide,
one or more polyols and a surface-active agent wherein the formulation has a
pH of 3.0 to 6.5, and the formulation is substantially free of a stabilizer that is
a polypeptide or protein.
The aqueous formulation as claimed in claim 64 wherein the polyol is selected
from the group consisting of lactose, sorbitol, trehalose, sucrose, mannose and
maltose and derivatives and homologs thereof.
The PYY(3-36) formulation as claimed in claims 64-66 wherein the surface-
active agent is selected from the group consisting of nonionic polyoxyethylene
ether, bile salts such, sodium glycocholate (SGC), deoxycholate (DOC),
derivatives of fusidic acid, sodium taurodihydrofusidate (STDHF), L-a-
phosphatidylcholine didecanoyl (DDPC), polysorbate 80 and polysorbate 20, a
polyethylene glycol (PEG), cetyl alcohol, polyvinylpyrolidone (PVP), a
polyvinyl alcohol (PVA), lanolin alcohol, and sorbitan monooleate.
The PYY(3-36) formulation as claimed in claim 64-66 comprising a
solubilizing agent and a chelating agent.
The PYY(3-36) formulation as claimed in claim 67 wherein the solubilizing
agent is selected from the group consisting of hydroxypropyl-ß-cyclodextran,
sulfobutylether-ß-cyclodextran and methyl-ß-cyclodextrin.
A P YY composition comprised of water, sodium citrate, citric acid, methyl-ß-
cyclodextrin, EDTA, lactose, sorbitol, DDPC and PYY(3-36) (SEQ ID NO:
2), wherein the formulation has a pH of 5.0± 0.3.
The PYY composition as claimed in claim 70 comprised of a preservative
selected from the group consisting of chlorobutanol and benzalkonium
chloride.
The composition as claimed in claim 71 wherein the preservative is
chlorobutanol.
A PYY composition comprised of water, chlorobutanol, sodium citrate, citric
acid, methyl-ß-cyclodextrin, EDTA, lactose, sorbitol, DDPC and PYY(3-36)
(SEQ ID NO: 2), wherein the formulation has a pH of 5.0± 0.3.
A of PYY(3-36) formulation in the manufacture of a medicament for treating
obesity or controlling eating in a patient, wherein mucosal administration of at
least 50 µg of said peptide in said medicament raises plasma concentrations of
said peptide in the subject by at least 5 pmole/1.
Pharmaceutical compositions and methods are described comprising at least one peptide YY compound and one or
more intranasal delivery-enhancing agents for enhanced nasal mucosal delivery of the peptide YY, for treating a variety of diseases
and conditions in mammalian subjects, including obesity. In one aspect, the intranasal delivery formulations and methods provide
enhanced delivery of peptide YY to the blood plasma or centra] nervous system (CNS) tissue or fluid, for example, by yielding a
peak concentration (Cmax) of the peptide YY in the blood plasma or CNS tissue or fluid of the subject that is 20% or greater compared
to a peak concentration of the peptide YY in the blood plasma or CNS tissue or fluid of the subject following administration to the
subject of a same concentration or dose of the peptide YY to the subject by subcutaneous injection.

Documents:


Patent Number 225189
Indian Patent Application Number 01373/KOLNP/2005
PG Journal Number 45/2008
Publication Date 07-Nov-2008
Grant Date 05-Nov-2008
Date of Filing 15-Jul-2005
Name of Patentee NASTECH PHARMACEUTICAL COMPANY INC
Applicant Address 3830 MONTE VILLA PARKWAY, BOTHELL, WA 98021-7266
Inventors:
# Inventor's Name Inventor's Address
1 QUAY STEVEN C 23632 HWY 99, STE. F PMB 454, EDMONDS, WA 98026-9224
2 BRANDT GORDON 790 KALMIA CT., ISSAQUAH, WA 98027
3 KLEPPE MARY S P.O. BOX 1535, KINGSTON, WA 98346
4 MACEVILLY CONOR J 3046 N.W. 60TH STREET, SEATTLE, WA 98107
PCT International Classification Number A61K 38/00
PCT International Application Number PCT/US2003/040538
PCT International Filing date 2003-12-17
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/493,226 2003-08-07 U.S.A.
2 60/510,785 2003-10-10 U.S.A.
3 60/517,290 2003-11-04 U.S.A.
4 60/518,812 2003-11-10 U.S.A.
5 10/322,266 2002-12-17 U.S.A.