Title of Invention

WATER-SOLUBLE IRON-CARBOHYDRATE DERIVATIVE COMPLEXES, THE PREPARATION THEREOF, AND MEDICAMENTS COMPRISING THEM

Abstract Water-soluble iron-carbohydrate derivative complex obtainable from an aqueous iron(III) salt solution and an aqueous solution of the product of the oxidation and subsequent derivatisation of one or more maltodextrins with an aqueous hypochlorite solution at an alkaline pH value, wherein when one maltodextrin is used its dextrose equivalent is from 5 to 20 and when a mixture of a plurality of maltodextrins is used the dextrose equivalent of the mixture is from 5 to 20 and the dextrose equivalent of each individual maltodextrin in the mixture is from 2 to 40, and the subsequent derivatisation is carried out with a suitable reagent, process for the preparation thereof, and medicament for the treatment and prophylaxis of iron deficiency states.
Full Text Water-soluble iron-carbohydrate derivative complexes, the
preparation thereof, and medicaments comprising them
The present invention provides water-soluble iron-
carbohydrate derivative complexes which are suitable for
the therapy of iron deficiency states, and the preparation
thereof, medicaments comprising them, and the use thereof
in the prophylaxis or therapy of iron deficiency states.
The medicaments are suitable in particular for parenteral
administration.
Anaemias caused by iron deficiency can be treated or
treated prophylactically by administration of medicaments
containing iron. The use of iron-carbohydrate complexes is
known for this purpose. A preparation that is frequently
used successfully in practice is based on a water-soluble
iron(III) hydroxide-saccharose complex (Danielson,
Salmonson, Derendorf, Geisser, Drug Res., Vol. 46 :
615-621, 1996) . Iron-dextran complexes as well as complexes
based on poorly obtainable pullulans (WO 02/46241) , which
have to be prepared under pressure at high temperatures and
with the involvement of hydrogenation steps, are also
described in the prior art for parenteral administration.
Further iron-carbohydrate complexes are conventional for
oral administration.
WO 2004/037865 in the name of the applicants discloses an
iron preparation which is preferably administrable
parenterally and which can be sterilised comparatively
simply; the previously known parenterally administrable
preparations based on saccharose or dextran were stable
only at temperatures up to 100°C, which made sterilisation
difficult. The preparation has reduced toxicity and
involves a reduced risk of dangerous anaphylactic shocks
inducible by dextran. The high stability of the complex
permits a high administration dose or a high administration
rate. The iron preparation can be produced from readily
obtainable starting materials without any particular
outlay. There are disclosed in particular water-soluble
iron(III)-carbohydrate complexes based on the oxidation
products of maltodextrins, and a process for the
preparation thereof. These iron(III)-carbohydrate complexes
are obtainable from an aqueous iron(III) salt solution and
an aqueous solution of the product of the oxidation of one
or more maltodextrins with an aqueous hypochlorite solution
at an alkaline pH value of, for example, from 8 to 12,
wherein when one maltodextrin is used its dextrose
equivalent is from 5 to 2 0 and when a mixture of a
plurality of maltodextrins is used the dextrose equivalent
of the mixture is from 5 to 2 0 and the dextrose equivalent
of the individual maltodextrins in the mixture is from 2 to
40.
T. Nakano et al., Nahrung/Food 47 (2002) No. 4, p. 274-278
describe a process for the phosphorylation of inter alia
dextrin by dry heating in the presence of phosphate.
Degrees of phosphorylation of the dextrin of 1.07 %, 2.42 %
and 3.2 % are mentioned, which are obtained in dependence
on the temperature and moisture content of the dextrin. The
resulting phosphorylated product is tested for its ability
to solubilise phosphate. The possibility of replacing
casein phosphopeptide as calcium phosphate absorption
increasing agent by phosphorylated dextrin is discussed.
Further possible synthesis methods for phosphorylated
dextrins are also mentioned in the mentioned document, in
particular drying with a phosphate-containing solution or
dry phosphorylation with orthophosphate, with heating and
in vacuo.
M.Z. Sitohy et al. , Starch/Stärke 53 (2001), 317-322
describe the phosphorylation of starch by mixing with a
solution of monosodium and disodium phosphate, filtering
off, drying, pulverisation and subsequent heating. The
phosphorylated product is tested for its hydrolytic
stability during acidic and enzymatic hydrolysis, and the
use thereof in admixture with polyacrylate and urea in
biodegradable plastics is proposed.
US 4,841,040 describes the preparation of phosphorylated
dextrins having a molecular weight of from 150 0 to
40,000 daltons and a degree of substitution of from 0.30 to
0.96 and their use as dispersing agents for aqueous
suspensions of minerals and inorganic pigments having a
high solids content, as a replacement for gum arable in
gumming and ink solutions for lithography, and as a
drilling fluid additive. The degree of substitution is
thereby defined by the molar ratio of the derivatised
anhydroglucose units to the total amount of anhydroglucose
units within a molecule. This is referred to hereinbelow as
the degree of molar substitution (MS) . The phosphorylated
dextrins are obtained by oxidation and depolytnerisation of
starch by reaction with sodium hypochlorite in alkaline
medium and subsequent or prior phosphorylation, for example
with phosphoric acid, phosphorus pentachloride, phosphoryl
chloride or polymeric sodium orthophosphates, in particular
sodium trimetaphosphate.
CH-544 779 describes a process for the preparation of
phosphorylated dextrins by heating a mixture of starch and
a phosphoric acid solution at a pH of less than 5, with a
reduced oxygen content, and then further heating in a
second stage, with an even lower oxygen content, until the
phosphorus compound is condensed with the starch product,
and subsequent cooling with a. reduced oxygen content. The
resulting dextrin phosphate has very high water solubility.
Its usability as a surface size for papers and in the
production of adhesives is likewise mentioned.
WO 2006/082043 describes in the introduction some processes
for the preparation of starch phosphates, for example
according to the Neukom process (US 2,884,412) by
suspension in an aqueous alkali phosphate solution,
filtration, drying and tempering at temperatures of about
14 0°C, in a homogeneous process using tetrapolyphosphoric
acid in the presence of tributylamine in dimethylformamide
(Towle et al., Methods Carbohydr. Chem. 6, (1972), 408-410)
or heterogeneously in a slurry process in benzene with
phosphoric anhydride (Tomasik et al. , Starch/Starke 43
(1991), 66-69) . The document itself proposes a process for
the preparation of highly substituted starch phosphates, in
which starch is dissolved in a mixture of phosphating agent
(in particular phosphate salts or urea phosphate) and water
and, if the phosphating agent is free of urea, urea, the
water is removed, and then a thermal reaction to give
starch phosphate takes place. The resulting starch
phosphate has a degree of substitution of phosphate groups
of from 0.01 to 2.0 and a very low content of carbamate
groups. The use of the resulting starch phosphates as an
additive in mineral or dispersion-bonded building material
systems, as an additive in pharmacy and cosmetics, as an
anionic component for polyelectrolyte complexes and as a
carrier material is proposed.
US 3,732,207 discloses the preparation of dextrin esters
using organic dibasic acid anhydrides, in particular
succinic anhydride or maleic anhydride, by heating starch
or dextrin having a residual moisture content of about 3 %
in the presence of the organic acid anhydride in an acidic
environment. A dextrin ester having a degree of molar
substitution of from 0.02 to 0.04 is obtained.
US 4,100,342 describes the preparation of dextrin esters by
reaction of dextrin with acid anhydrides of non-aromatic
carboxylic acids having from 2 to 4 carboxylic acid units
in acetic acid in the presence of a tertiary amine as
catalyst, and the use of the resulting dextrin esters as
biodegradable components for increasing the cleaning action
of detergents.
WO 2004/064850 and WO 92/04904 disclose dextrin sulfates
and their use, either alone or in combination with a
bacteriostatic agent, as an antiviral composition, in
particular for the treatment of HIV and other sexually
transmittable diseases. The dextrin sulfates having a
degree of substitution of up to 2 sulfate groups per
glucose unit are prepared by hydrolysis of starch and
subsequent sulfation. Trimethylamine/sulfur trioxide
complex in an aqueous alkaline medium yields mainly the 2-
sulfate, cyclamic acid in dimethylformamide yields the 6-
sulfate, and acetylation, subsequent sulfation with
trimethylamine/sulfur trioxide complex in dimethylform-
amide, and finally removal of the acetyl group with aqueous
sodium hydroxide yield the 3-sulfate. The action of the
dextrin sulfates against HIV and their antilipidaemic
action are likewise disclosed in these documents.
However, none of the mentioned documents describes the
formation of iron complexes with the resulting dextrin
derivatives.
The object of the present invention is, therefore, to
provide novel iron-carbohydrate complexes which are
suitable for the treatment of iron deficiency anaemia.
The object is achieved by the complexes according to
claim 1. Preferred forms of the complexes are defined in
claims 2 and 3.
The complexes according to the invention are obtained by
the process defined in claims 4 to 10.
Maltodextrins are used as starting material according to
the invention. These are readily obtainable starting
materials which are available commercially.
For the preparation of the ligands of the complexes
according to the invention, the maltodextrins are first
oxidised in aqueous solution with hypochlorite solution.
This process is already described in WO 2004/037865, the
totality of the disclosure of which is incorporated by
reference herein.
There are suitable, for example, solutions of alkali
hypochlorites, such as sodium hypochlorite solution.
Commercial solutions can be used. The concentrations of the
hypochlorite solutions are, for example, at least 13 wt.%,
preferably of the order of magnitude of from 14 to 16 wt.%,
in each case calculated as active chlorine. The solutions
are preferably used in an amount such that approximately
from 80 to 100 %, preferably approximately 90 %, of an
aldehyde group is oxidised per maltodextrin molecule. In
this manner, the reducing power determined by the glucose
contents of the maltodextrin molecules is reduced to
approximately 20 % or less, preferably to 10 % or less.
The oxidation takes place in alkaline solution, for example
a pH values of from 8 to 12, for example from 9 to 11. For
the oxidation it is possible to work, for example, at
temperatures of the order of magnitude of from 15 to 4 0°C,
preferably from 2 0 to 35°C. The reaction times are, for
example, of the order of magnitude of from 10 minutes to
4 hours, for example from 1 to 1.5 hours.
By means of the described procedure, the degree of
depolymerisation of the maltodextrins used is kept low.
Without giving a binding theory, it is assumed that the
oxidation takes place predominantly at the terminal
aldehyde group (or semiacetal group) of the maltodextrin
molecules. For the sake of simplicity, this synthesis step
is referred to hereinbelow as "C1 oxidation", but this term
is not intended to be binding.
It is also possible to catalyse the oxidation reaction of
the maltodextrins. The addition of bromide ions, for
example in the form of alkali bromides, for example sodium
bromide, is suitable for this purpose. The amount of
bromide added is not critical. It is kept as small as
possible in order to obtain an end product (Fe complex)
that is as simple to purify as possible. Catalytic amounts
are sufficient. As mentioned, the addition of bromide is
possible but not necessary.
In addition, it is also possible, for example, to use the
known ternary oxidation system hypochlorite/alkali
bromide/2,2,6, 6-tetramethylpiperidin-1-oxyl (TEMPO) for the
oxidation of the maltodextrins. The procedure of oxidising
maltodextrins with alkali bromide catalysis or using the
ternary TEMPO system is described, for example, by Thaburet
et al. in Carbohydrate Research 330 (2001) 21-29; the
procedure described therein can be used according to the
invention.
Working up and isolation of the oxidised maltodextrins are
carried out by adjusting the reaction solution to an
approximately neutral pH by means of suitable acids or
buffers, such as, for example, hydrochloric: acid, sulfuric
acid or acetic acid.
The oxidised reaction product can then be precipitated by
addition of a suitable solvent in which it is substantially
insoluble. An example of a suitable solvent is ethanol,
which is preferably used in a concentration of from 8 0 to
95 wt.%, particularly preferably from 90 to 94 wt.%, in a
volume ratio ethanol:reaction solution of approximately
from 1:5 to.1:10, preferably from 1:5 to 1:8. Further
suitable precipitation solvents are methanol, propanol or
acetone. The precipitate is then filtered off and dried in
a conventional manner.
Alternatively, the reaction solution can be purified by
means of dialysis or membrane filtration and the product
can be obtained by lyophilisation or spray drying.
It is also possible, however, to use the C1-oxidised
maltodextrin directly in the subsequent derivatisation step
without isolating it.
The subsequent derivatisation of the resulting C1-oxidised
products takes place by conventional processes, known to
the person skilled in the art, for the derivatisation of
sugars, for example by oxidation, esterification with mono-
or poly-functional inorganic or organic acids or acid
derivatives, carboxyalkylation, addition of organic
isocyanates, etherification, amidation, anhydride
formation, etc.
For example, an esterification can be carried out with
organic acids or acid derivatives. Any carboxylic acids or
reactive carboxylic acid derivatives known to the person
skilled in the art can be used for the esterif ication,
preferably acid chlorides, anhydrides or bromides. C1-C6-
Carboxylic acid derivatives are preferably used for the
esterification, particularly preferably acetic anhydride.
The esterification is carried out under conventional
reaction conditions, for example in aqueous solution or in
a suitable solvent such as, for example, formamide,
dimethylformamide, dimethyl sulfoxide or acetic acid. The
reaction in aqueous solution can take place, for example,
at a slightly basic pH of approximately from 7.5 to 10,
preferably from 8 to 9.5 (the pH can be adjusted and kept
constant during the reaction using any desired bases, for
example alkali or alkaline earth hydroxides such as sodium
or potassium hydroxide as well as alkali or alkaline earth
carbonates) by addition of the reactive carboxylic acid
derivative, for example acetyl chloride or acetic
anhydride. When a different solvent is used, the same
reagents are employed and suitable reaction conditions are
chosen. The reaction can take place in the mentioned
solvents at room temperature, with cooling or with heating.
The reaction time is, for example, from 0.5 to 2 hours,
preferably from 0.75 to 1.5 hours. Working up is carried
out as described for the C1 oxidation by precipitation,
filtering off and drying.
An esterification with polybasic organic carboxylic acids
can also take place in the same manner, for example the
preparation of succinic acid, maleic acid, fumaric acid,
glutaric acid or adipic acid esters, it being possible for
the second carboxyl group of the ester either to be free or
to be in the form of the alkyl ester. The anhydrides, mixed
anhydrides, chlorides or bromides or other reactive
derivatives of the polybasic carboxylic acids are suitable
for the preparation, for example in particular succinic
anhydride, maleic anhydride, glutaric anhydride, adipic
anhydride or fumaric acid dichloride. The reaction and
working up are carried out as described for the
esterification. Particular preference is given to
esterification with succinic anhydride to give succinyl
maltodextrin.
The C1-oxidised maltodextrins can likewise be reacted to
give carboxyalkyl derivatives. Suitable as reagent are
carboxyalkyl halides known to the person skilled in the
art, for example halocarboxylic acids such as chloro- or
bromo-carboxylic acids or their sodium or potassium salts,
for example C1-C6-carboxylic acids halogenated in any
desired position, such as, for example, a- or (3-
bromopropionic acid or, particularly preferably, chloro- or
bromo-acetic acid.
The reaction is carried out in a manner known to the person
skilled in the art, for example in aqueous solution or in a
suitable solvent such as, for example, formamide,
dimethylformamide, dimethyl sulfoxide or acetic acid. In
aqueous solution, the reaction is carried out, for example,
at a basic pH (pH 11 to 14, preferably approximately 12.5
to 14, adjustment using any desired bases, e.g. NaOH) . When
a different solvent is used, the same reagents are employed
and suitable reaction conditions are chosen. The reaction
can take place in the mentioned solvents at room
temperature, with cooling or with heating for, for example,
from 0.5 to 5 hours, preferably approximately from 2.5 to
3.5 hours. Working up and isolation are carried out as
described for the esterification.
The esterification with reactive derivatives of inorganic
acids, for example the sulfation or phosphation, likewise
take place by processes known to the person skilled in the
art.
The sulfation is carried out, for example, in aqueous
solution or in a suitable solvent such as, for example,
formamide, dimethylformamide, dimethyl sulfoxide or acetic
acid, using a suitable sulfation reagent, for example SO3-
trimethylamine complex or cyclamic acid, at room
temperature, with cooling or with heating, preferably, for
example, at 3 0°C for a suitable time, for example from
15 minutes to 2 hours, preferably for approximately
3 0 minutes. Then, when water is used as solvent, the pH of
the reaction solution is rendered strongly basic (e.g. to
pH 12-13) and the solution is stirred further at a suitable
temperature, for example at 3 0°C. After acidification to pH
9.5 to 11, preferably approximately 10.5, using a suitable
acid or a buffer, such as, for example, HCl, precipitation
and isolation are carried out as described for the C1
oxidation.
The phosphation is carried out according to any process
known to those skilled in the art. One possibility-
comprises dissolving dextrin in water with the phosphating
reagent and establishing a pH value of from 2 to 6,
preferably approximately 3. Suitable phosphating reagents
are any known reagents, a mixture of sodium dihydrogen
phosphate/disodium hydrogen phosphate in a molar ratio of
from 1:0.5 to 1:2.5, for example 1:1.8, preferably being
used. The reaction solution can be precipitated with
ethanol, methanol or acetone, for example, and the
precipitate can be isolated and dried, or the reaction
solution is concentrated to dryness by evaporation, for
example in a rotary evaporator, and dried further,
preferably at elevated temperature and in vacuo. After
grinding, the product is heated in the dry state, for
example to from 120 to 180°C, preferably from 150 to 170°C,
preferably in vacuo, and then ground again and subsequently
dissolved in water or a suitable solvent, preferably at an
elevated temperature of, for example, 50°C Insoluble
residues are then separated off, for example by
centrifugation or filtration, and the resulting solution is
purified by membrane filtration in order to remove free
orthophosphate. The filtration can be monitored by IR
spectroscopy or conductivity measurement. When all the
orthophosphate has been removed, the solution is
concentrated using a rotary evaporator and then
precipitated and isolated as described for the
esterification.
C2/C3-Oxidised derivatives can. be obtained by oxidation,
known to the person skilled in the art, of the C1-oxidised
maltodextrin with a suitable oxidising agent such as, for
example, NaOCl or NaIO4/NaOCl2. The oxidation is carried
out, for example, in aqueous solution or in a suitable
solvent such as dimethylformamide, formamide, dimethyl
sulfoxide or acetic acid, at room temperature, with heating
or with cooling. When water is used as solvent, the
reaction takes place at a slightly basic, constant pH of
from 7.5 to 9.5, preferably from 8.5 to 9.0, for example by
sodium hypochlorite at approximately 50°C. The pH is then
adjusted to neutral, for example by addition of HCl, and
the product is subsequently precipitated and isolated as
described for the esterification.
By using different amounts of the respective reagents for
the derivatisation, different degrees of molar substitution
can be achieved. The degree of molar substitution is
defined by the molar ratio of the derivatised
anhydroglucose units to the total amount of anhydroglucose
units within a molecule.
The products are investigated by IR spectroscopy. In this
manner it is possible to determine qualitatively whether
the desired functional group has been introduced into the
maltodextrin. The introduction of a carboxyl group, for
example of an acetyl group, succinyl group or carboxymethyl
group, can be monitored by augmentation of the band at
1740 cm-1 in the IR spectrum (C=O valence vibration of
COOR) . The successful C2/C3 oxidation can be monitored by
augmentation of the band at 1640 cm-1 (C=O valence vibration
of COO-) . The introduction of a sulfate group can be
confirmed by increase of the bands at 1260 and 830 cm-1
(valence vibrations of SO42-) . The introduction of a
phosphate group can also be confirmed qualitatively by 31P-
NMR spectroscopy. Polymer-bound monophosphate appears in
the form of broad signals at about 0 to 2 ppm, while free
monophosphate shows a sharp signal at about 0.7 ppm.
The quantitative determination of the degree of molar
substitution can be carried out by 1H-NMR spectroscopy or
13C-NMR spectroscopy, by relating the intensity of a signal
assigned to the introduced functional group to the
intensity of a signal of the maltodextrin that has not been
influenced by the derivatisation. In the case of
phosphation, the quantitative determination of the degree
of molar substitution can also be carried out by ICP-OES
(Inductively Coupled Plasma-Optical Emission Spectroscopy,
total phosphate content) and ion chromatography coupled
with conductivity measurement (content of free
monophosphate).
For the preparation of the complexes according to the
invention, the resulting oxidised derivatised maltodextrins
are reacted in aqueous solution with an iron(III) salt. To
this end, the oxidised derivatised maltodextrins can be
isolated and dissolved again; the resulting aqueous
solutions of the oxidised derivatised maltodextrins can,
however, also be used directly for further processing with
aqueous iron(III) solutions.
As iron(III) salts there can be used water-soluble salts of
inorganic or organic acids or mixtures thereof, such as
halides, for example chloride and bromide, or sulfates.
Physiologically acceptable salts are preferably used. An
aqueous solution of iron(III) chloride is particularly
preferably used.
It has been shown that the presence of chloride ions has an
advantageous effect on the complex formation. Chloride ions
can be added, for example, in the form of water-soluble
chlorides, such as alkali metal chlorides, e.g. sodium
chloride, potassium chloride or ammonium chloride.
Preference is given, as mentioned, to the use of iron (III)
in the form of the chloride.
For the reaction, it is possible, for example, to mix the
aqueous solution of the oxidised maltodextrin with an
aqueous solution of the iron(III) salt. The procedure
thereby is preferably such that the pH value of the mixture
of oxidised maltodextrin and iron (III) salt during and
immediately after mixing is initially strongly acidic or is
sufficiently low that hydrolysis of the iron (III) salt does
not occur, for example 2 or less, in order to avoid
undesirable precipitation of iron hydroxides. When
iron(III) chloride is used, it is generally not necessary
to add an acid because aqueous solutions of iron(III)
chloride can themselves be sufficiently acidic. When mixing
has taken place, the pH value can be raised, for example,
to values of the order of magnitude of equal to or greater
than 5, for example up to 11, 12, 13 or 14. Raising of the
pH value is preferably carried out slowly or gradually,
which can be effected, for example, by first adding a weak
base, for example to a pH of approximately 3; further
neutralisation can then take place using a stronger base.
Suitable weak bases are, for example, alkali or alkaline
earth carbonates, bicarbonates, such as sodium and
potassium carbonate or bicarbonate, or ammonia. Strong
bases are, for example, alkali or alkaline earth
hydroxides, such as sodium, potassium, calcium or magnesium
hydroxide.
The reaction can be furthered by heating. For example,
temperatures of the order of magnitude of from 15°C to the
boiling temperature can be applied. It is preferred to
increase the temperature gradually. For example, heating
can be carried out first to approximately from 15 to 70°C
and then the temperature can be gradually increased to
boiling.
The reaction times are, for example, of the order of
magnitude of from 15 minutes to several hours, e.g. from
2 0 minutes to 4 hours, for example from 25 to 7 0 minutes,
e.g. from 3 0 to 60 minutes.
The reaction can take place in the weakly acidic range, for
example at pH values of the order of magnitude of from 5 to
6. It has been shown, however, that it is advantageous,
although not necessary, to raise the pH value to higher
values, up to 11, 12, 13 or 14, in the course of the
complex formation. In order to complete the reaction, the
pH value can then be lowered further, for example to the
mentioned order of magnitude of from 5 to 6, by the
addition of an acid. As acids there can be used inorganic
or organic acids or mixtures thereof, in particular
hydrohalic acids, such as hydrogen chloride or aqueous
hydrochloric acid.
As mentioned, the complex formation is generally furthered
by heating. For example, in the preferred embodiment in
which the pH value is increased in the course of the
reaction to ranges of from beyond 5 to 11 or 14, it is
possible first to work at low temperatures of the order of
magnitude of from 15 to 70°C, for example from 40 to 60°C,
e.g. at approximately 50°C, whereupon, after again lowering
the pH value to values of, for example, the order of
magnitude of at least 5, gradual heating is carried out to
temperatures of from above 50°C to the boiling temperature.
The reaction times are of the order of magnitude of from
15 minutes to several hours and can vary according to the
reaction temperature. When the process is carried out with
the temporary application of pH values that are above 5, it
is possible to work at the elevated pH value for from 15 to
70 minutes, for example, e.g.. for from 30 to 60 minutes,
for example at temperatures up to 70°C, whereupon, after
lowering the pH value to the range of the order of
magnitude of at least 5, the reaction can be carried out
for a further 15 to 70 minutes, e.g. 3 0 to 60 minutes, at
temperatures of up to, for example, 70°C and optionally for
a further 15 to 70 minutes, e.g. 3 0 to 60 minutes, at
higher temperatures up to the boiling point.
When the reaction has been carried out, the resulting
solution can, for example, be cooled to room temperature
and optionally diluted and optionally filtered. After
cooling, the pH value can be adjusted to the neutral point
or slightly below, for example to values of from 5 to 7, by
addition of acid or base. There can be used as acids or
bases, for example, those mentioned above for the reaction.
The resulting solutions are purified and can be used
directly for the preparation of medicaments. However, it is
also possible to isolate the iron(III) complexes from the
solution, for example by precipitation with an alcohol,
such as an alkanol, for example ethanol. The isolation can
also be carried out by spray drying. Purification can be
carried out in a conventional manner, in particular in
order to remove salts. This can be effected, for example,
by reverse osmosis, it being possible for such a reverse
osmosis to be carried out, for example, before the spray
drying or before the direct use in medicaments.
The resulting iron(III)-carbohydrate complexes have, for
example, an iron content of from 10 to 40 % wt./wt., in
particular from 20 to 35 % wt./wt. They are readily soluble
in water. It is possible to prepare therefrom neutral
aqueous solutions having an iron content of, for example,
from 1 % wt./vol. to 20 % wt./vol. Such solutions can be
sterilised by means of heat. The weight-average molecular
weight Mw of the complexes so obtained is, for example,
from 80 kDa to 800 kDa, preferably from 80 to 650 kDa,
particularly preferably up to 350 kDa (determined by means
of gel permeation chromatography, for example as described
by Geisser et el. in Arzneim. Forsch/Drug Res. 42(II), 12,
1439-1452 (1992), Section 2.2.5.).
As mentioned, aqueous solutions can be prepared from the
complexes according to the invention. Such solutions are
suitable in particular for parenteral administration.
However, they can also be administered orally or topically.
They can be sterilised at high temperatures, e.g. at 121°C
and above, with short contact times of at least 15 minutes
with achievement of F0 = 15. F0 is the treatment time in
minutes at a variable temperature that corresponds to the
treatment time in minutes at 121°C calculated for an ideal
microorganism having a temperature coefficient of microbial
decomposition of 10. Preparations known hitherto had in
some cases to be sterile filtered at room temperature
and/or have preservatives, such as benzyl alcohol or
phenol, added thereto. Such working steps or additives are
not necessary according to the invention. It is possible to
introduce the solutions of the complexes into ampoules, for
example. For example, solutions of from 1 to 20 wt.%, for
example 5 wt.%, can be introduced into vessels, such as
ampoules or vials, of, for example, from 2 to 100 ml, for
example up to 50 ml. The preparation of the parenterally
administrable solutions can be carried out in a
conventional manner, optionally with the concomitant use of
additives conventional for parenteral solutions. The
solutions can be so formulated that they can be
administered as such by injection or as an infusion, for
example in saline solution. For oral or topical
administration, preparations can be formulated with
appropriate conventional excipients and auxiliary-
substances .
The invention therefore further provides medicaments which
are suitable in particular for parenteral, intravenous as
well as intramuscular administration and also for oral or
topical administration, and which can be used in particular
for the treatment of iron deficiency anaemias. The
invention therefore further provides the use of the
iron(III)-carbohydrate derivative complexes according to
the invention in the treatment and prophylaxis of iron
deficiency anaemias or in the preparation of medicaments
for in particular the parenteral treatment of iron
deficiency anaemias. The medicaments are suitable for use
in human and veterinary medicine.
According to the invention it is possible for the first
time to prepare iron complexes of maltodextrin derivatives.
Compared with the iron-maltodextrin complexes known from WO
2004/037865, the iron-maltodextrin derivative complexes
according to the invention permit a specific and fine
adjustment of the molecular weight over a wide range to
higher molecular weights, which was not possible with the
known complexes.
The majority of the iron-maltodextrin derivative complexes
exhibit a virtually unchanged degradation kinetics (© =
0.5) as compared with the iron-maltodextrin complexes known
from WO 2004/037865.
Most derivatised maltodextrin complexes exhibit increased
stability towards enzymatic degradation by amylase as
compared with underivatised maltodextrin, which can promote
retarded and uniform degradation of the iron-maltodextrin
derivative complexes according to the invention in the
body..
The iron yields of the complex derivatives according to the
invention reach 100 % (in particular in the case of the
sulfated complex derivatives), as compared with 87 to 93 %
in the known iron-maltodextrin complexes, which represents
an economic advantage for production on a commercial scale.
Examples
In the present description and the examples which follow,
dextrose equivalents are determined gravimetrically. To
this end, the maltodextrins are reacted in aqueous solution
with Fehling's solution, at boiling. The reaction takes
place quantitatively, i.e. until no further discolouration
of the Fehling's solution occurs. The precipitated
copper(I) oxide is dried to a constant weight at 105°C and
determined gravimetrically. The glucose content (dextrose
equivalent) is calculated from the resulting values as %
wt./wt. of maltodextrin dry substance. For example, it is
possible to work with the following solutions: 25 ml of
Fehling's solution I, mixed with 25 ml of Fehling's
solution II; 10 ml of aqueous maltodextrin solution (10 %
mol/vol.) (Fehling's solution I: 34.6 g of copper(II)
sulfate dissolved in 500 ml of water; Fehling's solution
II: 173 g of potassium sodium tartrate and 50 g of sodium
hydroxide, dissolved in 400 ml of water).
It is explained hereinbelow which methods and devices were
used to determine the respective properties of the
maltodextrin derivatives and iron complexes.
1H-NMR: Bruker Avance-400, 400 MHz, solution in D2O
referenced to H2O
13C-NMR: Bruker Avance-400, 100 MHz, solution in D2O
referenced externally to trimethylsilyl-tetradeutero-
propionic acid
31P-NMR: Bruker Avance-400, 162 MHz, solution in D2O
referenced externally to cone. H3PO4
IR: FT-IR Perkin Elmer 1725x, KBr pellet
ICP-OES: Horiba Jobin Yvon Ultima 2, sample dissolved in H2O
IC: Metrohm 733 IC Separation Center (incl. conductivity
detector), sample dissolved in H2O
GPC: Waters 515 HPLC pump, Waters 2410 Refractive Index
Detector, sample dissolved in H2O, pullulan as standard
Determination of Mw: see GPC
Determination of Mn: see GPC
Fe content: titrimetric determination with EDTA (e.g.
Jander Jahr, Massanalyse 15th Edition)
Degradation kinetics: P. Geisser, M. Baer, E. Schaub;
Structure/Histotoxicity Relationship of Parenteral Iron
Preparations; Arzneim.-Forsch./Drug Research 42 (II), 12,
1439-1452 (1992)
Analysis Jena Specord 205 spectral photometer, investigated
degree of degradation 50 % (O = 0.5)
Iron yield: amount of Fe isolated in g/amount of Fe used
in g
Example 1
Preparation of C1-oxidised maltodextrin
2 50 g of maltodextrin having a dextrose equivalent of 12
were dissolved in 750 ml of water. 1.4 g of NaBr were
added, and 78.4 g of NaOCl solution (14 to 16 wt.% active
chlorine) were metered in in the course of 30 minutes, the
pH being kept constant at 9.5 (±0.5) by addition of
3 0 wt.% NaOH. The pH was then adjusted to 7.0 using HCl
(20 wt.%), and the product was precipitated by addition of
ethanol (92 wt.%) in a volume ratio of 1:6
(solution:ethanol). The product was isolated by decanting
off the supernatant solution and was dried for 24 hours at
50°C and 125 mber.
Example 2
Preparation of C1-oxidised maltodextrin
10 0 g of maltodextrin (9.6 dextrose equivalents, determined
gravimetrically) are dissolved at 25°C, with stirring, in
300 ml of water and oxidised at pH 10 by addition of 30 g
of sodium hypochlorite solution (14 to 16 wt.% active
chlorine) and isolated and dried as in Example 1.
Example 3
Preparation of C1-oxidised maltodextrin
A mixture of 45 g of maltodextrin (6.6 dextrose
equivalents, determined gravimetrically) and 45 g of
maltodextrin (14.0 dextrose equivalents, determined
gravimetrically) is dissolved at 25°C, with stirring, in
300 ml of water and oxidised at pH 10 by addition of 25 g
of sodium hypochlorite solution (14 to 16 wt. % active
chlorine) and isolated and dried as in Example 1.
Examples 4 to 7
Acetylation
2 00 g of maltodextrin obtained in Example 1 (1.23 mol of
anhydroglucose) were dissolved at 25°C in 660 ml of water,
and the pH was adjusted to 8.5 using 30 wt. % NaOH. Acetic
anhydride was added at a rate of 1.7 ml/min. in various
amounts shown in Table 1, the pH being kept constant at 8.5
(± 0.5) by addition of 3 0 wt.. % NaOH. The solution was
stirred for one hour at a constant pH of 8.5 (± 0.5) and
then adjusted to 7. 0 using 2 0 wt. % HCl. The product was
precipitated with ethanol (92 wt.%) in a volume ratio of
1:6 (solution:ethanol). The product was isolated by
decanting off the supernatant solution and was dried for
24 hours at 50°C and 125 mbar.
By varying the amount of added acetic anhydride, different
degrees of acetylation were obtained. The results are shown
in Table 1.
Owing to the acetylation, the solubility of the
maltodextrin derivative in ethanol increases, which results
in a falling yield with an increasing degree of
substitution.
The degree of acetylation was determined qualitatively by
IR spectroscopy and quantitatively by NMR spectroscopy.
The acetylation can be monitored by IR spectroscopy by
augmentation of the band at 1740 cm-1 (C=0 valence vibration
of COOR). The degree of molar acetylation was determined by
1H-NMR spectroscopy by the ratio of the intensity of the CH3
signal at 2.0-2.3 ppm (acetyl group) to the intensity of
the signal at 3.0-4.5 ppm and 5-6 ppm (7 protons of the
anhydroglucose group).
Examples 8 to 11
Succinylation
2 00 g of C1-oxidised maltodextrin obtained in Example 1 were
dissolved in 655 ml of water. The pH was adjusted to 8.5
using 30 wt. % NaOH, and succinic anhydride was added in
portions at 25°C in the course of one hour, the pH being
kept constant at 8.5 (±0.5) by addition of 3 0 wt. % NaOH.
The pH was then adjusted to 7.0 by addition of 2 0 wt. % HC1
and the product was precipitated with ethanol (92 wt.%) in
a volume ratio solution:ethanol of 1:6. The product was
isolated by decanting off the supernatant solution and was
dried for 24 hours at 50°C and 125 mbar.
By varying the added amount of succinic anhydride,
different degrees of succinylation were obtained. The
results are shown in Table 2.
The succinylation did not significantly affect the
solubility of the oxidised maltodextrin.
The succinylation can be monitored qualitatively by IR
spectroscopy by augmentation of the band at 174 0 cm-1 (C=0
valence vibration of COOR/COOH). The degree of molar
succinylation was determined by 1H-NMR spectroscopy by the
ratio of the intensity of the two CH2 signals at 2.4-2.7 ppm
(succinyl group) to the intensity of the signal at
3.0-4.5 ppm and 5-6 ppm (7 protons of the anhydroglucose
group).
Examples 12 to 16
Carboxymethylation
200 g of C1-oxidised maltodextrin obtained in Example 1 were
dissolved in 660 ml of water. 118 g of solid NaOH were
added so that the pH was 13-14. Chloroacetic acid was added
in portions in the course of 2 0 minutes, and then stirring
was carried out at 25°C for 3 hours. The pH was then
adjusted to 7.0 by addition of 20 wt. % HC1, and the product
was precipitated with ethanol (92 wt.%) in a volume ratio
solution:ethanol of 1:6. The product was isolated by
decanting off the supernatant solution and was dried for
24 hours at 50°C and 125 mbar.
By varying the added amount of chloroacetic acid, different
degrees of carboxymethylation were obtained. The results
are shown in Table 3.
The degrees of carboxymethylation achieved did not
significantly affect the solubility of the oxidised
maltodextrin.
It is not possible to monitor the carboxymethylation by IR
spectroscopy because of the low degrees of substitution in
these examples. (No clear band at 174 0 cm-1 of the C=O
valence vibration.) The degree of molar carboxymethylation
was determined by 1H-NMR spectroscopy by the ratio of the
intensity of the anomeric protons at 5.6 ppm
(carboxymethylated anhydroglucose group) to the intensity
of the signal of the anomeric protons at 4.8-5.8 ppm
(anhydroglucose group without derivatisation).
Examples 17 to 20
Sulfation
200 g of C1-oxidised maltodextrin obtained in Example 1 were
dissolved in 600 ml of water and heated to 30°C. SO3-
trimethylamine complex was added and the mixture was
stirred at 3 0°C for 30 minutes (during which the suspension
changed into a solution). 40 wt.% NaOH (1.7 equivalents,
based on the molar amount of SO3-trimethylamine complex,
corresponding to 18-141 ml depending on the degree of
substitution) were added at a rate of 2.8 ml/min., and the
solution was stirred at 30°C for 2.5 hours. The pH was
adjusted to 10.5 with 2 0 wt.% HCl. The product was
precipitated with 92 wt.% ethanol in a volume ratio
solution:ethanol of 1:7 to 1:8. The product was isolated by
decanting off the supernatant solution and was dried for
24 hours at 50°C and 125 mbar.
By varying the added amount of SO3-triethylamine complex,
different degrees of sulfation were obtained. The results
are shown in Table 4.
The reason for the increasing yield of oxidised sulfated
maltodextrin is the decreasing solubility of the product in
ethanol.
The degree of sulfation can be monitored qualitatively by
IR spectroscopy (augmentation, of the bands at 1260 and
83 0 cm-1, valence vibrations of SO42) . The degree of molar
sulfation was determined by 13C-NMR spectroscopy by the
ratio of the intensity of the C1 signal at 96 ppm (sulfated
species) to the intensity of the C1 signal at 103 ppm (non-
sulfated species).
Examples 21 to 24
Phosphation
3 00 g of C1-oxidised maltodextrin obtained in Example 1,
NaH2PO4 and Na2HPO4 (molar ratio 1:1.8) were dissolved in
1.5 litres of water and the pH was adjusted to 3.0 using
20 wt.% HCl. The solution was concentrated to dryness by
evaporation in a rotary evaporator at 70°C and 125 mbar. The
residue was dried for 16 hours at 50°C and 12 5 mbar. This
product was ground and heated to 160°C over a period of
4 hours at 750 mbar. This material was ground again and
dissolved for one hour in water in a weight ratio of 1:4.4
(solid:water) at 50°C. The solution was cooled to 2 5°C and
the insoluble residues were separated off by centrifugation
(550 0 rpm for 1 hour).
In order to remove free orthophosphate, the resulting
solution was filtered by membrane filtration using a
nanofiltration membrane (Nitto-Denko NTR-7410, average NaCl
retention 10 %) at 22 bar and a flow rate of
180-210 litres/hour. The removal of the free orthophosphate
was monitored by IR spectroscopy of the washed fractions.
The solution of the oxidised phosphated maltodextrin was
concentrated to 1 litre in a rotary evaporator at 60°C and
80-250 mbar, and then the product was precipitated with
ethanol in a volume ratio of 1:6 (solution:ethanol). The
product was separated off by centrifugation of the
suspension (5500 rpm for 1 hour) and was dried for 24 hours
at 50°C and 125 mbar.
By varying the added amount of the mixture of NaH2PO4 and
Na2HPO4 in a molar ratio of 1:1.8, different degrees of
phosphation were obtained. The results are shown in
Table 5.
The degree of molar substitution was determined by ICP-OES
(Inductively Coupled Plasma-Optical Emission Spectroscopy,
total phosphate content) and ion chromatography coupled
with conductivity measurement (content of free
monophosphate).
A qualitative determination of the content of free
monophosphate was carried out by 31P-NMR spectroscopy.
Polymer-bound monophosphate appears in the form of broad
signals in the region of about 0-2 ppm, while free
monophosphate exhibits a sharp peak at about 0.7 ppm. The
broad signal at -10 ppm can be assigned to oligophosphates.
Examples 25 to 29
C2/C3 oxidation (two-stage synthesis)
200 g of C1-oxidised maltodextrin obtained in Example 1 were
dissolved in 600 ml of water and the solution was heated to
50°C. The pH was adjusted to 8.5 to 9.0 using 20 wt.% HCl,
and 20 g of NaOCl (14 to 16 % active chlorine) were added
in a single batch. The residual amount of NaOCl was added
at a rate of 5.8 ml/min., the pH being kept constant at 8.5
(± 0.5) by addition of 3 0 wt.% NaOH. The solution was
stirred for 1 hour at 50°C and pH 8.5 (± 0.5). The pH was
then adjusted to 7 using 20 wt.% HCl. The product was
precipitated with 92 wt.% ethanol in a volume ratio
solution:ethanol of 1:6. The product was isolated by
decanting off the supernatant solution and was dried for
24 hours at 50°C and 125 mbar.
Example 3 0
C1/C2/C3 oxidation (single-stage synthesis, in situ
derivatisation)
200 g of maltodextrin having a dextrose equivalent of 12
were dissolved in 660 ml of water and the solution was
heated to 50°C. 1.1 g of NaBr were added, and 135.2 g of
NaOCl solution (14 to 16 wt.% active chlorine) were metered
in in the course of 3 0 minutes, the pH being kept constant
at 9.5 (± 0.5) by addition of 3 0 wt.% NaOH. The solution
was stirred for 1 hour at 50°C and pH 9.5 (± 0.5) . The pH
was then adjusted to 7 using 20 wt.% HCl. The product was
precipitated with 92 wt.% ethanol in a volume ratio
solution:ethanol of 1:6. The product was isolated by
decanting off the supernatant solution and was dried for
2 4 hours at 5 0°C and 12 5 mbar.
By varying the added amount of NaOCl (14-16 % active
chlorine), different degrees of molar C2/C3 oxidation were
obtained. The results are shown in Table 6.
The variation in the isolated yield of the resulting
products is small.
It was possible to monitor the degree of C2/C3 oxidation by
IR spectroscopy by an augmentation of the band at 1640 cm"1
(C=0 valence vibration of COO-) .
The degree of molar C2/C3 oxidation was determined by 13C-NMR
spectroscopy by the ratio of the intensity of the COOH
signal at 175 and 176 ppm (oxidised C2 and C3) to the
intensity of the signal at 76-84 ppm (unoxidised C2) .
General process specification 1: Preparation of iron
complexes
The preparation of iron complexes from the resulting
oxidised derivatised maltodextrins was carried out in each
case using 100 g of the maltodextrin derivative:
To 352 g of iron(III) chloride solution (12 % wt./wt. Fe)
there were added, with stirring (paddle stirrer) , at room
temperature, first 100 g of the oxidised derivatised
maltodextrin dissolved in 300 ml of water, and then 554 g
of sodium carbonate solution (17.3 % wt./wt.).
A pH of 11 was then established by addition of sodium
hydroxide solution, and the solution was heated to 50°C and
maintained at 5 0°C for 3 0 minutes. The mixture was then
acidified to a pH of 5 to 6 by addition of hydrochloric
acid, and the solution was maintained at 50°C for a further
3 0 minutes and then heated to 97-98°C and maintained at that
temperature for 3 0 minutes. After cooling the solution to
room temperature, the pH value was adjusted to 6-7 by
addition of sodium hydroxide solution. The solution was
then filtered over a sterile filter and the complex was
isolated by precipitation with ethanol in a ratio of 1:0.85
and was dried in vacuo at 50°C.
Examples 31 to 33
Acetylated iron complexes
According to general process specification 1, the
acetylated iron complexes 31 to 33 were obtained from the
maltodextrin derivatives obtained in Examples 5 to 7, the
properties of which are summarised in Table 7 below, in
each case compared with a standard preparation which was
likewise prepared according to general process
specification 1 from C1-oxidised but not derivatised
maltodextrin as obtained in Example 1.
The use of acetylated maltodextrin derivatives having a
degree of molar substitution > 0.61 resulted in instable
products.
The acestylated iron complexes exhibited increased iron
contents as compared with the standard and rising molecular
weights as the degree of substitution increased. The
degradation kinetics at 50 % showed similar values compared
with the standard. The Fe yields of the acetylated iron
complexes reached 97 %.
Examples 34 to 36
Succinylated iron complexes
According to general process specification 1, the
succinylated iron complexes 34 to 3 6 were obtained from the
maltodextrin derivatives obtained in Examples 9 to 11, the
properties of which are summarised in Table 8 below, in
each case compared with a standard preparation which was
likewise prepared according to general process
specification 1 from C1-oxidised but not derivatised
maltodextrin as obtained in Example 1.
The use of succinylated maltodextrin derivatives having a
degree of molar substitution > 0.07 resulted in instable
products.
The succinylated iron complexes exhibited slightly reduced
iron contents as compared with the standard as well as
rising molecular weights as the degree of substitution
increased. The degradation kinetics at 50 % showed similar
values compared with the standard, with one exception. The
Fe yields of the succinylated iron complexes reached 94 %.
Examples 3 7 to 3 8
Carboxymethylated iron complexes
According to general process specification 1, the
carboxymethylated iron complexes 37 and 38 were obtained
from the maltodextrin derivatives obtained in Examples 15
to 16, the properties of which are summarised in Table 9
below, in each case compared with a standard preparation
which was likewise prepared according to general process
specification 1 from C1-oxidised but not derivatised
maltodextrin as obtained in Example 1.
The use of carboxymethylated maltodextrin derivatives
having a degree of molar substitution > 0.01 resulted in
instable products.
The iron contents of the carboxymethylated iron complexes
were found to be slightly reduced as compared with the
standard, and the molecular weights rose as the degree of
substitution increased. The degradation kinetics at 50 %
showed almost identical values compared with the standard.
The Fe yields of the carboxymethylated iron complexes
reached 97 %.
Examples 3 9 to 41
C2/C3-oxidised iron complexes
According to general process specification 1, the C2/C3-
oxidised iron complexes 3 9 to 41 were obtained from the
maltodextrin derivatives obtained in Examples 27, 2 8 and
29, the properties of which are summarised in Table 10
below, in each case compared with a standard preparation
which was likewise prepared according to general process
specification 1 from C1-oxidised but not derivatised
maltodextrin as obtained in Example 1.
The use of C2/C3-oxidised maltodextrin derivatives having a
degree of molar substitution > 0.01 resulted in instable
products.
The iron contents did not exhibit a uniform tendency, the
molecular weights rose as the degree of substitution
increased. The degradation kinetics at 50 % showed almost
identical values compared with the standard. The Fe yields
of the C2/C3-oxidised iron complexes reached 95 %.
Examples 42 to 44
Sulfated iron complexes (multi-stage synthesis)
According to general process specification 1, the sulfated
iron complexes 42 to 44 were obtained in multi-stage
syntheses from the maltodextrin derivatives obtained in
Examples 18 to 20, the properties of which are summarised
in Table 11 below, in each case compared with a standard
preparation which was likewise prepared according to
general process specification 1 from C1-oxidised but not
derivatised maltodextrin as obtained in Example 1.
Example 45
Sulfated iron complex (single-stage synthesis, in situ
derivatisation)
100 g of maltodextrin having a dextrose equivalent of 12
were dissolved in 300 ml of water. 0.7 g of NaBr was added,
and 28.7 g of NaOCl solution (14 to 16 wt.% active
chlorine) were metered in in the course of 3 0 minutes, the
pH being kept constant at 9.5 (± 0.5) by addition of
3 0 wt.% NaOH. The solution was then heated to 30°C, 14.4 g
of SO3-trimethylamine complex were added, and stirring was
then carried out for 3 0 minutes at 3 0°C. 17.6 ml of 40 wt.%
NaOH were then metered in, and stirring was carried out for
1 hour at 3 0°C.
After cooling the solution to 20-25°C, 352 g of iron (III)
chloride solution {12 % wt./wt. Fe) were added, with
stirring, and then 554 g of sodium carbonate solution
(17.3 % wt./wt .) were metered, in. A pH of 11 was then
established by addition of sodium hydroxide solution, and
the solution was heated to 50°C and maintained at 50°C for
30 minutes. The mixture was then acidified to a pH of 5 to
6 by addition of hydrochloric acid, and the solution was
maintained at 50°C for a further 3 0 minutes and then heated
to 97-98°C and maintained at that temperature for
3 0 minutes. After cooling the solution to room temperature,
the pH value was adjusted to 6-7 by addition of sodium
hydroxide solution. The solution was then filtered over a
sterile filter and the complex was isolated by-
precipitation with ethanol in a ratio of 1:0.85 and was
dried in vacuo at 50°C.
The use of sulfated maltodextrin derivatives having a
degree of molar substitution > 0.27 resulted in instable
products.
The iron contents of the sulfated iron complexes remained
almost constant as the degree of substitution increased.
The molecular weights of the iron complexes synthesised in
a multi-stage synthesis rose; as the degree of substitution
increased. The degradation kinetics at 50 % showed
increased values compared with the standard. The Fe yields
of the sulfated iron complexes reached 100 %.
WE CLAIM
1. Water-soluble iron-carbohydrate derivative complex
obtainable from an aqueous iron(III) salt solution and an
aqueous solution of the product of the oxidation and
subsequent derivatisation of one or more rnaltodextrins,
wherein the oxidation is carried out with an aqueous
hypochlorite solution at a pH value in the alkaline range,
wherein when one maltodextrin is used its dextrose
equivalent is from 5 to 20 and when a mixture of a
plurality of rnaltodextrins is used the dextrose equivalent
of the mixture is from 5 to 20 and the dextrose equivalent
of the individual rnaltodextrins in the mixture is from 2 to
40, and the subsequent derivatisation is carried out with a
suitable reagent.
2. Water-soluble iron-carbohydrate complex according to
claim 1, wherein the maltodextrin derivatives obtained by
the oxidation and derivatisation are selected from esters
of monobasic or polybasic carboxylic acids, C2/C3 oxidation
products, carboxyalkylation products, carbamates, ethers,
amides, anhydrides and esters of inorganic acids.
3. Complex according to claim 1 or 2, wherein the
derivatives of maltodextrin obtained by oxidation and
derivatisation are selected from carboxylic acid esters,
mixed dicarboxylic acid esters, carboxyalkylation products,
C2/C3 oxidation products, phosphates and sulfates.
4. Process for the preparation of an iron-carbohydrate
complex according to one of more of claims 1 to 3,
characterised in that one or more maltodextrins is/are
oxidised in aqueous solution, at an alkaline pH value, with
an aqueous hypochlorite solution, the subsequent
derivatisation is carried out with a suitable reagent, and
the resulting solution is reacted with the aqueous solution
of an iron(III) salt, wherein when one maltodextrin is used
its dextrose equivalent is from 5 to 20 and when a mixture
of a plurality of maltodextrins is used the dextrose
equivalent of the mixture is from 5 to 2 0 and the dextrose
equivalent of the individual maltodextrins in the mixture
is from 2 to 40.
5. Process according to claim 4, wherein the
derivatisation of the oxidised maltodextrin is carried out
by one of the following processes:
a) esterification with organic or inorganic acids or
derivatives thereof,
b) oxidation,
c) carboxyalkylation,
d) etherification,
e) amidation,
f) carbamate formation,
g) anhydride formation.
6. Process according to claim 4 or 5, wherein the
derivatisation is carried out by one of the following
processes:
a) carboxylation with monobasic carboxylic acids or
carboxylic acid derivatives,
b) C2/C3 oxidation,
c) carboxylation with dibasic carboxylic acids or
carboxylic acid, derivatives,
d) carboxyalkylation,
e) phosphation,
f) sulfation.
7. Process according to one or more of claims 4 to 6,
characterised in that the oxidation of the maltodextrin or
maltodextrins is carried out in the presence of bromide
ions.
8. Process according to any one of claims 4 to 7,
characterised in that the iron (III) salt used is iron (III)
chloride.
9. Process according to one or more of claims 4 to 8,
characterised in that oxidised, derivatised maltodextrin
and iron(III) salt are mixed into an aqueous solution
having a pH value that is sufficiently low that hydrolysis
of the iron (III) salt does not occur, whereupon the pH
value is raised to from 5 to 12 by addition of base.
10. Process according to claim 9, characterised in that
the reaction is carried out for from 15 minutes to several
hours at a temperature of from 15°C to the boiling point.
11. Medicament comprising the aqueous solution of an iron-
carbohydrate derivative complex according to claim 1 to 3,
or obtainable according to any one of claims 4 to 10.
12. Medicament according to claim 11, characterised in
that it is formulated for parenteral or oral
administration.
13. Use of the iron-carbohydrate derivative complexes of
claim 1 to 3 or obtained according to any one of claims 4
to 10 in the treatment or prophylaxis of iron deficiency
states.
14. Use of the iron-carbohydrate derivative complexes of
claim 1 to 3 or obtained according to any one of claims 4
to 10 in the preparation of a medicament for the treatment
or prophylaxis of iron deficiency states.
15. Water-soluble iron-carbohydrate derivative complex
according to claim 1 to 3 for the treatment or prophylaxis
of iron deficiency states.


Water-soluble iron-carbohydrate derivative complex
obtainable from an aqueous iron(III) salt solution and an
aqueous solution of the product of the oxidation and
subsequent derivatisation of one or more maltodextrins with
an aqueous hypochlorite solution at an alkaline pH value,
wherein when one maltodextrin is used its dextrose
equivalent is from 5 to 20 and when a mixture of a
plurality of maltodextrins is used the dextrose equivalent
of the mixture is from 5 to 20 and the dextrose equivalent
of each individual maltodextrin in the mixture is from 2 to
40, and the subsequent derivatisation is carried out with a
suitable reagent, process for the preparation thereof, and
medicament for the treatment and prophylaxis of iron
deficiency states.

Documents:

3704-kolnp-2009-(05-01-2015)-CORRESPONDENCE.pdf

3704-KOLNP-2009-(05-06-2014)-PETITION UNDER SECTION 8 (1).pdf

3704-KOLNP-2009-(25-11-2013)-ANNEXURE TO FORM 3.pdf

3704-KOLNP-2009-(25-11-2013)-CLAIMS.pdf

3704-KOLNP-2009-(25-11-2013)-CORRESPONDENCE.pdf

3704-KOLNP-2009-(25-11-2013)-FORM-5.pdf

3704-KOLNP-2009-(25-11-2013)-OTHERS.pdf

3704-kolnp-2009-abstract.pdf

3704-kolnp-2009-claims.pdf

3704-KOLNP-2009-CORRESPONDENCE 1.1.pdf

3704-KOLNP-2009-CORRESPONDENCE 1.2.pdf

3704-KOLNP-2009-CORRESPONDENCE 1.3.pdf

3704-kolnp-2009-correspondence.pdf

3704-kolnp-2009-description (complete).pdf

3704-kolnp-2009-form 1.pdf

3704-KOLNP-2009-FORM 18.pdf

3704-kolnp-2009-form 2.pdf

3704-kolnp-2009-form 3.pdf

3704-kolnp-2009-form 5.pdf

3704-kolnp-2009-international publication.pdf

3704-kolnp-2009-international search report.pdf

3704-KOLNP-2009-PA.pdf

3704-KOLNP-2009-PCT IPER.pdf

3704-kolnp-2009-pct priority document notification.pdf

3704-kolnp-2009-pct request form.pdf

3704-KOLNP-2009-SCHEDULE.pdf

3704-kolnp-2009-specification.pdf


Patent Number 265191
Indian Patent Application Number 3704/KOLNP/2009
PG Journal Number 07/2015
Publication Date 13-Feb-2015
Grant Date 12-Feb-2015
Date of Filing 23-Oct-2009
Name of Patentee VIFOR (INTERNATIONAL) AG
Applicant Address RECHENSTRASSE 37 9001 ST. GALLEN SWITZERLAND
Inventors:
# Inventor's Name Inventor's Address
1 DR. ERIK PHILIPP GRUENTALSTRASSE 8 9303 WITTENBACH SWITZERLAND
2 DR. PETER GEISSER MARWEESSTRAβE 8 9014 ST. GALLEN SWITZERLAND
3 DR. STEFAN REIM WOLFGANGSTRASSE 6 9014 ST. GALLEN SWITZERLAND
4 DR. FELIX FUNK ROEMERSTRASSE 177B 8404 WINTERTHUR SWITZERLAND
5 DR. HANS-MARTIN MUELLER KREUZSTRASSE 28 9032 ENGELBURG SWITZERLAND
PCT International Classification Number C08B31/18; C08B31/00
PCT International Application Number PCT/EP2008/056276
PCT International Filing date 2008-05-21
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 07109081.5 2007-05-29 EPO