Title of Invention

VACCINE COMPOSITION COMPRISING IMMUNOGENIC POLYPEPTIDES

Abstract The present invention relates to, inter alia, a method of raising an immune response against a pathogen which comprises administering (i) one or more first immunogenic polypeptides derived from said pathogen; (ii) one or more adenoviral vectors comprising one or more heterologous polynucleotides encoding one or more second immunogenic polypeptides derived from said pathogen; and (iii) an adjuvant; wherein the one or more first immunogenic polypeptides, the one or more adenoviral vectors and the adjuvant are administered concomitantly. The invention also relates to vaccines, pharmaceutical compositions, kits and uses employing said polypeptides, adenoviral vectors and adjuvants.
Full Text Novel Method and Compositions
Field of the invention
This invention relates to novel vaccine compositions and their use in the stimulation of
immune responses in mammals, especially humans, and in particular for the prevention and
treatment of infection by pathogens. In particular it relates to compositions capable of inducing
CD4+ and CD8+ T-cell responses as well as antibody responses in subjects without recourse to
complex prime-boost schedules.
Background to the invention
Inactivated whole organisms have been used in successful vaccination since the late
nineteenth century. In more recent times, vaccines involving the administration of extracts,
subunits, toxoids and capsular polysaccharides have been employed. Since genetic
engineering techniques have been available, the use of recombinant proteins has been a
favoured strategy, obviating many of the risks associated with use of purified proteins from
natural sources.
Early vaccine approaches were based on the administration of proteins which stimulated
some aspect of the immune response in vivo. Subsequently it was appreciated that immune
responses could also be raised by administration of DNA which could be transcribed and
translated by the host into an immunogenic protein.
The mammalian immune response has two key components: the humoral response and
the cell-mediated response. The humoral response involves the generation of circulating
antibodies which will bind to the antigen to which they are specific, thereby neutralising the
antigen and favouring its subsequent clearance by a process involving other cells that are either
cytotoxic or phagocytic. B-cells are responsible for generating antibodies (plasma B cells), as
well as holding immunological humoral memory (memory B-cells), i.e. the ability to recognise an
antigen some years after first exposure to it eg through vaccination. The cell mediated
response involves the interplay of numerous different types of cells, among which are the T
cells. T-cells are divided into a number of different subsets, mainly the CD4+ and CD8+ T cells.
Antigen-presenting cells (APC) such as macrophages and dendritic cells act as sentinels
of the immune system, screening the body for foreign antigens. When extracellular foreign
antigens are detected by APC, these antigens are phagocytosed (engulfed) inside the APC
where they will be processed into smaller peptides. These peptides are subsequently presented
on major histocompatibility complex class II (MHC II) molecules at the surface of the APC where
they can be recognised by antigen-specific T lymphocytes expressing the CD4 surface
molecules (CD4+ T cells). When CD4+ T cells recognise the antigen to which they are specific
on MHCII molecules in the presence of additional adequate co-stimulatory signals, they become
activated and secrete an array of cytokines that subsequently activate the other arms of the
immune system. In general, CD4+T cells are classified into T helper 1 (Th1) or T helper 2 (Th2)
subsets depending on the type of response they generate following antigen recognition. Upon
recognition of a peptide-MHC II complex, Th1 CD4+ T cells secrete interleukins and cytokines
such as interferon gamma thereby activating macrophages to release toxic chemicals such as
nitric oxide and reactive oxygen/nitrogen species. IL-2 and TNF-alpha are also commonly
categorized as Th1 cytokines. In contrast, Th2 CD4+ T cells generally secrete interleukins such
aslL-4, IL-5 orlL-13.
Other functions of the T helper CD4+ T cells include providing help to activate B cells to
produce and release antibodies. They can also participate to the activation of antigen-specific
CD8+ T cells, the other major T cell subset beside CD4+ T cells.
CD8+ T cells recognize the peptide to which they are specific when it is presented on
the surface of a host cell by major histocompatibility class I (MHC I) molecules in the presence
of appropriate costimulatory signals. In order to be presented on MHC I molecules, a foreign
antigen need to directly access the inside of the cell (the cytosol or nucleus) such as it is the
case when a virus or intracellular bacteria directly penetrate a host cell or after DNA vaccination.
Inside the cell, the antigen is processed into small peptides that will be loaded onto MHC I
molecules that are redirected to the surface of the cell. Upon activation CD8+T cells secrete an
array of cytokines such as interferon gamma that activates macrophages and other cells. In
particular, a subset of these CD8+ T cells secretes lytic and cytotoxic molecules (e.g. granzyme,
perforin) upon activation. Such CD8+ T cells are referred to as cytotoxic T cells.
More recently, an alternative pathway of antigen presentation involving the loading of
extracellular antigens or fragments thereof onto MHCI complexes has been described and
called "cross-presentation".
The nature of the T-cell response is also influenced by the composition of the adjuvant
used in a vaccine. For instance, adjuvants containing MPL & QS21 have been shown to
activate Th1 CD4+ T cells to secrete IFN-gamma (Stewart et al. Vaccine. 2006, 24 (42-
43):6483-92).
Whereas adjuvants are well known to have value in enhancing immune responses to
protein antigens, they have not generally been used in conjunction with DNA or DNA-based
vector vaccination. There are several hypotheses as to why adjuvants have not been used in
conjunction with DNA-vector based vaccines. Indeed, interferences between the adjuvant and
the vector may have an impact on their stability. In addition, one might expect that adding an
adjuvant to an attenuated vector could increase the reactogenicity induced by such product.
Finally, increasing the immunogenicity of a DNA-vector based vaccine may lead to an enhanced
neutralizing immune response against the vector itself, thereby precluding any boosting effect of
subsequent injections of the same vector-based vaccine. In fact, in a vaccination protocol
directed towards protection against P. falciparum infection, Jones et al (2001, J Infect Diseases
183, 303-312) have reported an adverse outcome after combining DNA, recombinant protein
and adjuvant as a boosting composition following a prime by DNA. Indeed, the levels of
parasitemia were significantly lower in a group in which the boosting composition contained
protein and adjuvant only. It was concluded that use of the combination of DNA, recombinant
protein and adjuvant in this protocol adversely affected the outcome on parasitemia as well as
antibody responses.
On the other hand, there has been a report of enhancement of the efficacy of an
adjuvanted DNA-based vector vaccine (Ganne et al. Vaccine (1994) 12(13) 1190-1196). In
particular, the enhanced efficacy of a replication-defective adenovirus-vectored vaccine by the
addition of oil adjuvants was correlated with higher antibody levels but the impact on CD4 and
CD8 T cell responses was not reported.
The use of an apathogenic virus as an adjuvant has been disclosed in WO2007/016715.
It was not mentioned that said virus could contain any heterologous polynucleotide.
It is generally thought that stimulation of both CD4+ and CD8+ cells are needed for
optimal protective immunity, especially in certain diseases such as HIV infection/AIDS. In order
to induce an optimal immune response either prophylactically or therapeutically, stimulation of
both CD4+ and CD8+ cells is desirable. This is one of the main goal of "prime-boost"
vaccination strategies in which the alternate administration of protein-based vaccines (inducing
mostly CD4+T cells) with DNA-vector based vaccines, i.e. naked DNA, viral vectors or
intracellular bacterial vectors such as listeria, (inducing mostly CD8+T cells) or vice versa most
likely activates both CD4+ and CD8+ T cell responses.
However, although prime-boost vaccine strategies may generally give rise to a greater or
more balanced response, the requirement to vaccinate on more than one occasion and certainly
on more than two occasions can be burdensome or even unviable, especially in mass
immunization programs for the developing world.
Furthermore, as already mentioned above, it is often not possible to boost the viral
vector component because of immunity that may have been raised against the vector itself.
Thus the objects of the invention include one or more of the following: (a) to provide a
complete vaccination protocol and a vaccine composition which stimulates the production of
CD4+ and/or CD8+ cells and/or antibodies and in particular which obviates or mitigates the
need for repeated immunizations; (b) to provide a vaccination protocol and a vaccine
composition which better stimulates production of CD4+ cells and/or CD8+cells and/or
antibodies relative to vaccine compositions containing an immunogenic polypeptide alone or a
polynucleotide alone or relative to a conventional prime-boost protocol involving separate
administration of immunogenic polypeptide and polynucleotide; (c) to provide a vaccine
composition which stimulates or better stimulates Th1 responses; (d) to provide a vaccine
composition and vaccination protocol in which required doses of components, especially viral
vectors, are minimised; and (e) more generally to provide a useful vaccine composition and
vaccination protocol for treatment or prevention of diseases caused by pathogens. By "better
stimulates" is meant that the intensity and/or persistence of the response is enhanced.
Summary of the invention
Thus according to the invention there is provided a method of raising an immune
response against a pathogen which comprises administering (i) one or more first immunogenic
polypeptides derived from said pathogen; (ii) one or more adenoviral vectors comprising one or
more heterologous polynucleotides encoding one or more second immunogenic polypeptides
derived from said pathogen; and (iii) an adjuvant; wherein the one or more first immunogenic
polypeptides, the one or more adenoviral vectors and the adjuvant are administered
concomitantly.
According to a specific aspect of the invention there is provided a vaccine composition
comprising (i) one or more first immunogenic polypeptides derived from a pathogen; (ii) one or
more adenoviral vectors comprising one or more heterologous polynucleotide encoding one or
more second immunogenic polypeptides derived from said pathogen; and (iii) an adjuvant.
There is also provided an immunogenic composition comprising (i) one or more first
immunogenic polypeptides derived from a pathogen; (ii) one or more adenoviral vectors
comprising one or more heterologous polynucleotides encoding one or more second
immunogenic polypeptides derived from said pathogen; and (iii) an adjuvant.
Said vaccines and immunogenic compositions suitably stimulate production of pathogen-
specific CD4+ T-cells and/or CD8+ T-cells and/or antibodies.
By "pathogen-specific CD4+ T-cells and/or CD8+ T-cells and/or antibodies" is meant
CD4+ T-cells and/or CD8+ T-cells and/or antibodies which specifically recognise the whole
pathogen or a part (eg an immunogenic subunit) thereof. By "specifically recognise" is meant
that the CD4+ T-cells and/or CD8+ T-cells and/or antibodies recognise in an immunospecific
rather than a non-specific manner said pathogen (or part thereof).
There is also provided a method of stimulating an immune response in a mammal which
comprises administering to a subject an immunologically effective amount of such a
composition.
There is also provided use of such a composition in the manufacture of a medicament
for stimulating an immune response in a mammal.
There is also provided such a composition for use in stimulating an immune response in
a mammal.
There is also provided a method of stimulating the production of pathogen-specific
CD4+ T-cells and/or CD8+ T-cells and/or antibodies in mammals which comprises administering
to said mammal (i) one or more first immunogenic polypeptides derived from a pathogen; (ii)
one or more adenoviral vectors comprising one or more heterologous polynucleotides encoding
one or more second immunogenic polypeptides derived from said pathogen; and (iii) an
adjuvant; wherein the one or more first immunogenic polypeptides, the one or more adenoviral
vectors and the adjuvant are administered concomitantly, for example by administering an
immunologically effective amount of an aforeseaid composition.
There is also provided use of aforesaid compositions in the manufacture of a
medicament for stimulating the production of pathogen specific CD4+ and/or CD8+ cells and/or
antibodies in mammals.
For example, production of CD4+ T-cells or CD8+ T-cells or antibodies is stimulated.
Suitably production of 2 and especially 3 of CD4+ T-cells and/or CD8+ T-cells and/or
antibodies is stimulated.
Suitably production of CD8+ T-cells is stimulated. Suitably production of CD4+ and
CD8+ T-cells is stimulated. Suitably production of CD4+ and CD8+ T-cells and antibodies is
stimulated.
Alternatively suitably production of CD4+ T-cells is stimulated. Suitably production of
CD4+ and antibodies is stimulated.
Alternatively suitably production of antibodies is stimulated.
The methods of the invention are suitably intended to provide the steps adequate for a
complete method for raising an immune response (although the method may, if desired, be
repeated). Therefore suitably the methods do not involve use of a priming dose of any
immunogenic polypeptide or polynucleotide (e.g. in the form of a vector such as an adenoviral
vector) encoding any immunogenic polypeptide.
For example there is provided a method of raising an immune response against a
pathogen which consists of (a) administering (i) one or more first immunogenic polypeptides
derived from said pathogen; (ii) one or more adenoviral vectors comprising one or more
heterologous polynucleotides encoding one or more second immunogenic polypeptides derived
from said pathogen; and (iii) an adjuvant; wherein the one or more immunogenic polypeptide,
the one or more adenoviral vector and the adjuvant are administered concomitantly; and (b)
optionally repeating the steps of (a).
The steps of the method may be repeated (e.g. repeated once) if a repeat gives rise to
an improved immune response. An adequate response, at least as far as a T-cell response is
concerned, may be obtained without any need for repetition.
There is also provided a method of raising an immune response against a pathogen
which comprises (a) administering (i) one or more first immunogenic polypeptides derived from
said pathogen; (ii) one or more adenoviral vectors comprising one or more heterologous
polynucleotides encoding one or more second immunogenic polypeptides derived from said
pathogen; and (iii) an adjuvant; wherein the one or more first immunogenic polypeptides, the
one or more adenoviral vectors and the adjuvant are administered concomitantly; and wherein
the method does not involve administering any priming dose of immunogenic polypeptide or
polynucleotide encoding immunogenic polypeptide.
There is also provided a kit comprising (i) one or more first immunogenic polypeptides
derived from a pathogen; (ii) one or more adenoviral vectors comprising one or more
heterologous polynucleotides encoding one or more second immunogenic polypeptides derived
from said pathogen; and (iii) an adjuvant; and in particular comprising (i) one or more first
immunogenic polypeptides derived from a pathogen and an adjuvant; and (ii) one or more
second adenoviral vectors comprising one or more heterologous polynucleotides encoding one
or more immunogenic polypeptides derived from said pathogen; for use in a method according
to the invention.
Compositions and methods of the invention may be useful for the prevention of infection
by pathogens in naive subjects, or prevention of re-infection in subjects who have previously
been infected by pathogen or treatment of subjects who have been infected by pathogen.
Brief description of the figures
Figure 1 shows a graphical representation of the construction of plasmid p73i-Tgrn
Figures 2-8 show the results of experiments discussed in Example 1, specifically:
Figures 2a, 2b, 3a, 3b: CD4+ and CD8+ T-cell responses in response to restimulation by pools
of peptides derived from p24, RT, Nef and p17 following various immunization protocols and at
different timepoints;
Figure 4: antibody responses against F4;
Figures 5-8 antibody responses against F4 components p24, RT, p17 and Nef respectively;
Figure 9 shows the results of experiments discussed in Example 2, specifically:
CD4+ T-cell responses in response to restimulation by pools of peptides derived from p24 and
RT following various immunization protocols;
Figures 10-12 show the results of experiments discussed in Example 3, specifically:
Figure 10 shows the lymphoproliferative response of rabbit PBMC against peptide pools
covering the F4 sequence;
Figure 11 shows the timecourse of antibody responses against F4;
Figures 12a and 12b shows antibody responses (on day 77) against F4 components p24 and
RT respectively;
Figure 13 shows the quantification of HIV-1-specific CD4 T cells;
Figure 14 shows distribution of the frequency of F4-specific CD4 T cells 7 days after two
immunizations;
The above recited sequences may be employed as polypeptides or polynucletides encoding
polypeptides of use in exemplary aspects of the invention. Said polypeptides may consist of or
comprise the above mentioned sequences. Initial Met residues are optional. N-terminal His
residues (including His residues immediately following an initial Met, as in SEQ ID No 9) are
optional or an N-terminal His tag of a different length may be employed (eg typically up to 6 His
residues may be employed to facilitate isolation of the protein). Analogue proteins which have
significant sequence identity eg greater than 80% eg greater than 90% eg greater than 95% eg
greater than 99% sequence identity over the whole length of the reference sequence may be
employed, especially when the analogue protein has a similar function and particularly when the
analogue protein is similarly immunogenic. For example up to 20 eg up to 10 eg 1-5
susbtitutions (eg conservative substitutions) may be tolerated. Nucleic acids which differ from
those recited above which encode the same proteins, or the aforementioned analogue proteins,
may be employed. Sequence identity may be determined by conventional means eg using
BLAST. In one specific variant of SEQ ID No 16 that may be mentioned, reside 398 is Ser
and not Cys.
Detailed description of the invention.
As used herein the term "concomitantly" means wherein the one or more immunogenic
polypeptides, the one or more adenoviral vectors and the adjuvant are administered within a
period of no more than 12 hours eg within a period of no more than 1 hour, typically on one
occasion e.g. in the course of the same visit to the health professional, for example the one or
more immunogenic polypeptides, the one or more adenoviral vectors and the adjuvant are
administered sequentially or simultaneously.
As used herein, the term "epitope" refers to an immunogenic amino acid sequence. An
epitope may refer to an a minimum amino acid sequence of typically 6-8 amino acids which
minimum sequence is immunogenic when removed from its natural context, for example when
transplanted into a heterologous polypeptide. An epitope may also refer to that portion of a
protein which is immunogenic, where the polypeptide containing the epitope is referred to as the
antigen (or sometimes "polypeptide antigen"). A polypeptide or antigen may contain one or
more (eg 2 or 3 or more) distinct epitopes. The term "epitope" embraces B-cell and T-cell
epitopes. The term "T-cell epitope" embraces CD4+ T-cell epitopes and CD8+ T-cell epitopes
(sometimes also referred to as CTL epitopes).
The term "immunogenic polypeptide" refers to a polypeptide which is immunogenic, that
is to say it is capable of eliciting an immune response in a mammal, and therefore contains one
or more epitopes (eg T-cell and/or B-cell epitopes). Immunogenic polypeptides may contain
one or more polypeptide antigens eg in an unnatural arrangement such as in a fusion protein.
Immunogenic polypeptides will typically be recombinant proteins produced eg by
expression in a heterologous host such as a bacterial host, in yeast or in cultured mammalian
cells.
The term "polypeptide derived from a pathogen" means a polypeptide which partially or
wholly contains sequences (i.e. antigens) which occur naturally in pathogens or bear a high
degree of sequence identity thereto (eg more than 95% identity over a stretch of at least 10 eg
at least 20 amino acids).
Immunogenic polypeptides may contain one or more (eg 1, 2, 3 or 4) polypeptide
antigens.
Unless otherwise specified, an "immune response" may be a cellular and/or a humoral
response.
In one embodiment of the invention one or more of said one or more first immunogenic
polypeptides is substantially the same as one or more of said one or more second mmunogenic
polypeptides. For example one of the at least one first immunogenic polypeptides and one of
the at least one second immunogenic polypeptides may have an overall sequence identity of
90% or more eg 95% or more eg 98% or 99% or more over the length of one or other
immunogenic polypeptides.
In another embodiment of the invention one or more of said one or more first
immunogenic polypeptides contains at least one antigen which is substantially the same as an
antigen contained in one or more of said one or more second immunogenic polypeptides. For
example one of the at least one first immunogenic polypeptides and one of the at least one
second immunogenic polypeptides may have an overall sequence identity of 90% or more eg
95% or more eg 98% or 99% or more over a stretch of 20 amino acids or more eg 40 amino
acids or more eg 60 amino acids or more.
Suitably one or more first immunogenic polypeptides comprise at least one T cell
epitope.
Suitably one or more second immunogenic polypeptides comprise at least one T cell
epitope.
Suitably the one or more first immunogenic polypeptides comprise at least one B cell
epitope.
Suitably the one or more second immunogenic polypeptides comprise at least one B cell
epitope
In another embodiment of the invention one or more of said one or more first
immunogenic polypeptides and one or more of said one or more second immunogenic
polypeptides share one or more identical B-cell and/or T-cell epitopes. Suitably they share one
or more identical amino acid sequences of length 10 amino acids or more eg 15 amino acids or
more eg 25 amino acids or more.
In another embodiment of the invention, none of the one or more of said one or more
first immunogenic polypeptides is substantially the same as or contains any antigen in common
with one or more of said one or more second immunogenic polypeptides, for example they may
have an overall sequence identity of less than 90% over a stretch of 20 amino acids or more eg
40 amino acids or more eg 60 amino acids or more.
Thus, they may not share any B-cell or T-cell epitopes. For example, they may note
share any identical amino acid sequences of length 10 amino acids or more eg at 15 amino
acids or more eg 25 amino acids or more.
In one specific embodiment of the invention a first immunogenic polypeptide and a
second immunogenic polypeptide contain the same antigens in the same arrangement or in a
different arrangement (eg in a different arrangement). By "different arrangement" is meant that
they may be arranged in a different order and/or they may be divided. In another specific
embodiment of the invention a first immunogenic polypeptide and a second immunogenic
polypeptide are the same.
The composition according to the invention may contain one first immunogenic
polypeptide as the only immunogenic polypeptide in the composition. Alternatively the
composition according to the invention may contain more than one first immunogenic
polypeptides eg 2 or 3 or 4 or more immunogenic polypeptides.
The composition according to the invention may comprise one adenoviral vector.
Alternatively it may comprise more than one adenoviral vector eg 2 adenoviral vectors.
In compositions according to the invention a adenoviral vector may comprise a
heterologous polynucleotide which encodes for one second immunogenic polypeptide or it may
comprise more than one heterologous polynucleotide which together encode for more than one
second immunogenic polypeptide under the control of more than one promoter.
As well as for prophylactic vaccination, the compositions of the invention may also be
used in individuals that are already infected with pathogen, and result in improved
immunological control of the established infection. This is of particular interest when the
pathogen is HIV. In the case of HIV, this control is believed to be achieved by CD8-positive T
cells that specifically recognize HIV-infected cells. Such CD8-positive T cell response is
maintained by the presence of HIV-specific CD4-positive helper T cells. Therefore, the induction
of both types of immune response is particularly useful, and can be achieved by combining
different vaccine compositions. A combination of an adjuvanted protein and a recombinant
adenovirus is of particular interest. The HIV-infected patients that will benefit from the above-
described vaccination are either in the primary infection, latency or terminal phase of HIV
infection at the time of vaccination. The patients may or may not undergo other therapeutic
treatment interventions against pathogen (in the case of HIV - for example highly active
antiretroviral therapy) at the time of vaccination.
Antigens
Antigens of use according to the invention are derived from pathogens.
Pathogens include viruses, bacteria, protozoa and other parasitic organisms harmful to
mammals including man.
Suitable polypeptide antigens to be administered as polypeptide or polynucleotide
encoding polypeptide according to the invention include antigens derived from HIV (eg HIV-1),
human herpes viruses (such as gH, gL gM gB gC gK gE or gD or derivatives thereof or
Immediate Early protein such as ICP27 , ICP 47, ICP4, ICP36 from HSV1 or HSV2),
cytomegalovirus, especially Human, (such as gB or derivatives thereof), Epstein Barr virus
(such as gp350 or derivatives thereof), Varicella Zoster Virus (such as gpl, II, III and IE63), or
from a hepatitis virus such as hepatitis B virus (for example Hepatitis B Surface antigen, PreS1,
PreS2 and Surface env proteins, Hepatitis B core antigen or pol), hepatitis C virus (eg Core,
E1, E2, P7, NS2, NS3, NS4A, NS4B, NS5A and B) and hepatitis E virus antigen, or from other
viral pathogens, such as paramyxoviruses: Respiratory Syncytial virus (such as F and G
proteins or derivatives thereof), or antigens from parainfluenza virus, measles virus, mumps
virus, human papilloma viruses (for example HPV6, 11,16, 18, eg L1, L2, E1, E2, E3, E4, E5,
E6, E7), flaviviruses (e.g. Yellow Fever Virus, Dengue Virus, Tick-borne encephalitis virus,
Japanese Encephalitis Virus) or Influenza virus (such as haemaggluttin, nucleoprotein, NA, or M
proteins, or combinations thereof), or antigens derived from bacterial pathogens such as
Neisseria spp, including N. gonorrhea and N. meningitidis, eg, transferrin-binding proteins,
lactoferrin binding proteins, PilC, adhesins); S. pyogenes (for example M proteins or fragments
thereof, C5A protease, S. agalactiae, S. mutans; H. ducreyi; Moraxella spp, including M
catarrhalis, also known as Branhamella catarrhalis (for example high and low molecular weight
adhesins and invasinsj; Bordetella spp, including B. pertussis (for example pertactin, pertussis
toxin or derivatives thereof, filamenteous hemagglutinin, adenylate cyclase, fimbriae), B.
parapertussis and B. bronchiseptica; Mycobacterium spp., including M. tuberculosis, M. bovis,
M. leprae, M. avium, M. paratuberculosis, M. smegmatis; Legionella spp, including L
pneumophila; Escherichia spp, including enterotoxic E. coli (for example colonization factors,
heat-labile toxin or derivatives thereof, heat-stable toxin or derivatives thereof),
enterohemorragic E. coll, enteropathogenic E. coli (for example Shiga toxin-like toxin or
derivatives thereof); Vibrio spp, including V. cholera (for example cholera toxin or derivatives
thereof); Shigella spp, including S. sonnei, S. dysenteriae, S. flexnerii; Yersinia spp, including Y.
enterocolitica (for example a Yop protein) , Y. pestis, Y. pseudotuberculosis; Campylobacter
spp, including C. jejuni (for example toxins, adhesins and invasins) and C. coli; Salmonella spp,
including S. typhi, S. paratyphi, S. choleraesuis, S. enteritidis; Listeria spp., including L.
monocytogenes; Helicobacter spp, including H. pylori (for example urease, catalase,
vacuolating toxin); Pseudomonas spp, including P. aeruginosa; Staphylococcus spp., including
5. aureus, S. epidermidis; Enterococcus spp., including E. faecalis, E. faecium; Clostridium
spp., including C. tetani (for example tetanus toxin and derivative thereof), C. botulinum (for
example botulinum toxin and derivative thereof), C. difficile (for example Clostridium toxins A or
B and derivatives thereof); Bacillus spp., including B. anthracis (for example botulinum toxin and
derivatives thereof; Corynebacterium spp., including C. diphtheriae (for example diphtheria
toxin and derivatives thereof); Borrelia spp., including S. burgdorferi (for example OspA, OspC,
DbpA, DbpB), B. garinii (for example OspA, OspC, DbpA, DbpB), S. afzelii (for example OspA,
OspC, DbpA, DbpB,), B. andersonii (for example OspA, OspC, DbpA, DbpB), B. hermsii;
Ehrlichia spp., including E. equi and the agent of the Human Granulocytic Ehrlichiosis;
Rickettsia spp, including R. rickettsii; Chlamydia spp., including C. trachomatis, C. pneumoniae,
C. psittaci; Leptospira spp., including L interrogans; Treponema spp., including T. pallidum (for
example the rare outer membrane proteins,), T. denticola, T. hyodysenteriae; or derived from
parasites such as Plasmodium spp., including P. falciparum and P. vivax; Toxoplasma spp.,
including T. gondii (for example SAG2, SAG3, Tg34); Entamoeba spp., including E. histolytica;
Babesia spp., including B. microti; Trypanosoma spp., including T. cruzi; Giardia spp., including
6. lamblia; leishmania spp., including L major Pneumocystis spp., including P. carinii;
Trichomonas spp., including T. vaginalis; Schisostoma spp., including S. mansoni, or derived
from yeast such as Candida spp., including C. albicans; Cryptococcus spp., including C.
neoformans.
Further bacterial antigens include antigens derived from Streptococcus spp, including S.
pneumoniae (PsaA, PspA, streptolysin, choline-binding proteins) and the protein antigen
Pneumolysin (Biochem Biophys Acta, 1989, 67,1007; Rubins et al., Microbial Pathogenesis,
25, 337-342), and mutant detoxified derivatives thereof (WO 90/06951; WO 99/03884). Other
bacterial antigens include antigens derived from Haemophilus spp., including H. influenzae type
B (for example PRP and conjugates thereof), non typeable H. influenzae, for example OMP26,
high molecular weight adhesins, P5, P6, protein D and lipoprotein D, and fimbrin and fimbrin
derived peptides (US 5,843,464) or multiple copy variants or fusion proteins thereof.
In particular, the methods or compositions of the present invention may be used to
protect against or treat viral disorders such as those caused by Hepatitis B virus, Hepatitis C
virus, Human papilloma virus, Human immunodeficiency virus (HIV), or Herpes simplex virus;
bacterial diseases such as those caused by Mycobacterium tuberculosis (TB) or Chlamydia sp;
and protozoal infections such as malaria.
It is to be recognised that these specific disease states, pathogens and antigens have
been referred to by way of example only, and are not intended to be limiting upon the scope of
the present invention.
TB antigens
The pathogen may, for example, be Mycobacterium tuberculosis.
Exemplary antigens derived from M. tuberculosis are for example alpha-crystallin
(HspX), HBHA, Rv1753, Rv2386, Rv2707, Rv2557, Rv2558, RPFs: Rv0837c, Rv1884c,
Rv2389c, Rv2450, Rv1009, aceA (Rv0467), ESAT6, Tb38-1, Ag85A, -B or -C, MPT 44,
MPT59, MPT45, HSP10, HSP65, HSP70, HSP 75, HSP90, PPD 19kDa [Rv3763], PPD, 38kDa
[Rv0934]), PstS1, (RV0932), Sod A (Rv3846), Rv2031c, 16kDa, Ra12, TbH9, Ra35, Tb38-1,
Erd 14, DPV, MTI, MSL, DPPD, mTCC1, mTCC2, hTCC1 (WO 99/51748) and hTCC2, and
especially Mtb32a, Ra35, Ra12, DPV, MSL, MTI, Tb38-1, mTCC1, TbH9 (Mtb39a), hTCC1,
mTCC2 and DPPD. Antigens derived from M. tuberculosis also include fusion proteins and
variants thereof where at least two, or for example, three polypeptides of M. tuberculosis are
fused into a larger protein. Such fusions may comprise or consist of Ra12-TbH9-Ra35, Erd14-
DPV-MTI, DPV-MTI-MSL, Erd 14-DPV-MTI-MSL-mTCC2, Erd 14-DPV-MTI-MSL, DPV-MTI-MSL-
mTCC2, TbH9-DPV-MTI (WO 99/51748), Ra12-Tbh9-Ra35-Ag85B and Ra12-Tbh9-Ra35-
mTCC2. A particular Ra12-Tbh9-Ra35 sequence that may be mentioned is defined by SEQ ID
No 6 of WO2006/117240 together with variants in which Ser 704 of that sequence is mutated to
other than serine, eg to Ala, and derivatives thereof incorporating an N-terminal His tag of an
appropriate length (eg SEQ ID No 2 or 4 of WO2006/117240). See also SEQ ID No 10 which
is a sequence containing an optional starting M and an optional N-terminal His-His tag
(positions 2 and 3) and in which the Ala mutated relative to the wild-type Ser is at position 706.
Chlamydia antigens
The pathogen may, for example, be a Chlamydia sp. eg C trachomatis.
Exemplary antigens derived from Chlamydia sp eg C trachomatis are selected from
CT858, CT 089, CT875, MOMP, CT622, PmpD, PmpG and fragments thereof, SWIB and
immunogenic fragments of any one thereof (such as PmpDpd and PmpGpd) and combinations
thereof. Preferred combinations of antigens include CT858, CT089 and CT875. Specific
sequences and combinations that may be employed are described in WO2006/104890.
Plasmodium antigens
The pathogen may, for example be a parasite that causes malaria such as a
Plasmodium sp. eg P falciparum or P vivax.
For example, antigens derived from P falciparum include circumsporozoite protein (CS
protein),PfEMP-1, Pfs 16 antigen, MSP-1, MSP-3, LSA-1, LSA-3, AMA-1 and TRAP. A
particular hybrid antigen that may be mentioned is RTS. RTS is a hybrid protein comprising
substantially all the C-terminal portion of the circumsporozoite (CS) protein of P.falciparum
linked via four amino acids of the preS2 portion of Hepatitis B surface antigen to the surface (S)
antigen of hepatitis B virus. When expressed in yeast RTS is produced as a lipoprotein particle,
and when it is co-expressed with the S antigen from HBV it produces a mixed particle known as
RTS,S The structure or RTS and RTS.S is disclosed in WO 93/10152. TRAP antigens are
described in WO 90/01496. Other Plasmodium antigens include P. falciparum EBA, GLURP,
RAP1, RAP2, Sequestrin, Pf332, STARP, SALSA, PfEXPI, Pfs25, Pfs28, PFS27/25, Pfs48/45,
Pfs230 and their analogues in other Plasmodium spp. One embodiment of the present
invention is a composition comprising RTS.S or CS protein or a fragment thereof such as the
CS portion of RTS, S in combination with one or more further malarial antigens which may be
selected for example from the group consisting of MSP-1, MSP-3, AMA-1, Pfs 16, LSA-1 or
LSA-3. Possible antigens from P vivax include circumsporozoite protein (CS protein) and Duffy
antigen binding protein and immunogenic fragments thereof, such as PvRII (see eg
WO02/12292).
Thus in one suitable embodiment of the invention, the first and second immunogenic
polypeptides are selected from antigens derived from Plasmodium falciparum and/or
Plasmodium vivax.
For example, the first and/or second immunogenic polypeptides are selected from antigens
derived from Plasmodium falciparum and/or Plasmodium vivax are selected from RTS (eg as
RTS.S), circumsporozoite (CS) protein, MSP-1, MSP-3, AMA-1, LSA-1, LSA-3 and
immunogenic derivatives thereof or immunogenic fragments thereof.
One specific derivative that may be mentioned is the hybrid protein known as RTS,
especially when presented in the form of a mixed particle known as RTS.S.
An exemplary RTS sequence is shown in SEQ ID No 14.
An exemplary P. falciparum CS protein-derived antigen is shown in SEQ ID No 12. This
particular sequence corresponds to the CSP sequence of P.falciparum (3D7 strain), which also
contains a 19 aa insertion coming from 7G8 strain ( 81-100).
In one specific embodiment of the invention, a first immunogenic polypeptide is RTS.S
and a second immunogenic polypeptide is the CS protein from Plasmodium falciparum or an
immunogenic fragment thereof.
HPV antigens
The pathogen may, for example, be a Human Papilloma Virus.
Thus antigens of use in the present invention may, for example, be derived from the
Human Papilloma Virus (HPV) considered to be responsible for genital warts (HPV 6 or HPV 11
and others;, and/or the HPV viruses responsible for cervical cancer (HPV16, HPV18, HPV33,
HPV51, HPV56, HPV31, HPV45, HPV58, HPV52 and others;. In one embodiment the forms of
genital wart prophylactic, or therapeutic, compositions comprise L1 particles or capsomers, and
fusion proteins comprising one or more antigens selected from the HPV proteins E1, E2, E5 E6,
E7, L1, and L2. In one embodiment the forms of fusion protein are: L2E7 as disclosed in
W096/26277, and proteinD (1/3)-E7 disclosed in PCT/EP98/05285.
A preferred HPV cervical infection or cancer, prophylaxis or therapeutic composition may
comprise HPV 16 or 18 antigens. For example, L1 or L2 antigen monomers, or L1 or L2
antigens presented together as a virus like particle (VLP) or the L1 alone protein presented
alone in a VLP or capsomer structure. Such antigens, virus like particles and capsomer are per
se known. See for example WO94/00152, WO94/20137, WO94/05792, and WO93/02184.
Additional early proteins may be included alone or as fusion proteins such as E7, E2 or
preferably E5 for example; particularly preferred embodiments of this includes a VLP comprising
L1E7 fusion proteins (WO 96/11272). In one embodiment the HPV 16 antigens comprise the
early proteins E6 or E7 in fusion with a protein D carrier to form Protein D - E6 or E7 fusions
from HPV 16, or combinations thereof; or combinations of E6 or E7 with L2 (WO 96/26277).
Alternatively the HPV 16 or 18 early proteins E6 and E7, may be presented in a single
molecule, preferably a Protein D- E6/E7 fusion. Such a composition may optionally provide
either or both E6 and E7 proteins from HPV 18, preferably in the form of a Protein D - E6 or
Protein D - E7 fusion protein or Protein D E6/E7 fusion protein. Additionally antigens from other
HPV strains, preferably from strains HPV 31 or 33 may be employed.
HIV antigens
The pathogen may, for example, be HIV eg HIV-1.
Thus, antigens may be selected from HIV derived antigens, particularly HIV-1 derived
antigens.
HIV Tat and Nef proteins are early proteins, that is, they are expressed early in infection
and in the absence of structural protein.
The Nef gene encodes an early accessory HIV protein which has been shown to
possess several activities. For example, the Nef protein is known to cause the removal of CD4,
the HIV receptor, from the cell surface, although the biological importance of this function is
debated. Additionally Nef interacts with the signal pathway of T cells and induces an active
state, which in turn may promote more efficient gene expression. Some HIV isolates have
mutations or deletions in this region, which cause them not to encode functional protein and are
severely compromised in their replication and pathogenesis in vivo.
The Gag gene is translated from the full-length RNA to yield a precursor polyprotein
which is subsequently cleaved into 3-5 capsid proteins; the matrix protein p17, capsid protein
p24 and nucleic acid binding protein (Fundamental Virology, Fields BN, Knipe DM and Howley
M 1996 2. Fields Virology vol 2 1996).
The Gag gene gives rise to the 55-kilodalton (Kd) Gag precursor protein, also called
p55, which is expressed from the unspliced viral mRNA. During translation, the N terminus of
p55 is myristoylated, triggering its association with the cytoplasmic aspect of cell membranes.
The membrane-associated Gag polyprotein recruits two copies of the viral genomic RNA along
with other viral and cellular proteins that triggers the budding of the viral particle from the
surface of an infected cell. After budding, p55 is cleaved by the viral y encoded protease (a
product of the Pol gene) during the process of viral maturation into four smaller proteins
designated MA (matrix [p17]), CA (capsid [p24]), NC (nucleocapsid [p9]), and p6.(4).
In addition to the 3 major Gag proteins (p17, p24 and p9), all Gag precursors contain
several other regions, which are cleaved out and remain in the virion as peptides of various
sizes. These proteins have different roles e.g. the p2 protein has a proposed role in regulating
activity of the protease and contributes to the correct timing of proteolytic processing.
The MA polypeptide is derived from the N-terminal, myristoylated end of p55. Most MA
molecules remain attached to the inner surface of the virion lipid bilayer, stabilizing the particle.
A subset of MA is recruited inside the deeper layers of the virion where it becomes part of the
complex which escorts the viral DNA to the nucleus. These MA molecules facilitate the nuclear
transport of the viral genome because a karyophilic signal on MA is recognized by the cellular
nuclear import machinery. This phenomenon allows HIV to infect non-dividing cells, an unusual
property for a retrovirus.
The p24 (CA) protein forms the conical core of viral particles. Cyclophilin A has been
demonstrated to interact with the p24 region of p55 leading to its incorporation into HIV
particles. The interaction between Gag and cyclophilin A is essential because the disruption of
this interaction by cyclosporine inhibits viral replication.
The NC region of Gag is responsible for specifically recognizing the so-called packaging
signal of HIV. The packaging signal consists of four stem loop structures located near the 5"
end of the viral RNA, and is sufficient to mediate the incorporation of a heterologous RNA into
HIV-1 virions. NC binds to the packaging signal through interactions mediated by two zinc-
finger motifs. NC also facilitates reverse transcription.
The p6 polypeptide region mediates interactions between p55 Gag and the accessory
protein Vpr, leading to the incorporation of Vpr into assembling virions. The p6 region also
contains a so-called late domain which is required for the efficient release of budding virions
from an infected cell.
The Pol gene encodes three proteins having the activities needed by the virus in early
infection, reverse transcriptase RT, protease, and the integrase protein needed for integration of
viral DNA into cellular DNA. The primary product of Pol is cleaved by the virion protease to
yield the amino terminal RT peptide which contains activities necessary for DNA synthesis (RNA
and DNA directed DNA polymerase, ribonuclease H) and carboxy terminal integrase protein.
HIV RT is a heterodimer of full-length RT (p66) and a cleavage product (p51) lacking the
carboxy terminal RNase H domain.
RT is one of the most highly conserved proteins encoded by the retroviral genome. Two
major activities of RT are the DNA Pol and ribonuclease H. The DNA Pol activity of RT uses
RNA and DNA as templates interchangeably and like all DNA polymerases known is unable to
initiate DNA synthesis de novo, but requires a pre existing molecule to serve as a primer (RNA).
The RNase H activity inherent in all RT proteins plays the essential role early in
replication of removing the RNA genome as DNA synthesis proceeds. It selectively degrades
the RNA from all RNA - DNA hybrid molecules. Structurally the polymerase and ribo H occupy
separate, non-overlapping domains within the Pol covering the amino two thirds of the Pol.
The p66 catalytic subunit is folded into 5 distinct subdomains. The amino terminal 23 of
these have the portion with RT activity. Carboxy terminal to these is the RNase H domain.
After infection of the host cell, the retroviral RNA genome is copied into linear double
stranded DNA by the reverse transcriptase that is present in the infecting particle. The
integrase (reviewed in Skalka AM '99 Adv in Virus Res 52 271-273) recognises the ends of the
viral DNA, trims them and accompanies the viral DNA to a host chromosomal site to catalyse
integration. Many sites in the host DNA can be targets for integration. Although the integrase is
sufficient to catalyse integration in vitro, it is not the only protein associated with the viral DNA in
vivo - the large protein - viral DNA complex isolated from the infected cells has been denoted
the pre integration complex. This facilitates the acquisition of the host cell genes by progeny
viral genomes.
The integrase is made up of 3 distinct domains, the N terminal domain, the catalytic core
and the C terminal domain. The catalytic core domain contains all of the requirements for the
chemistry of polynucleotidyl transfer.
HiV-1 derived antigens for us in the invention may thus for example be selected from
Gag (for example full length Gag), p17 (a portion of Gag), p24 (another portion of Gag), p41,
p40, Pol (for example full length Pol), RT (a portion of Pol), p51 (a portion of RT), integrase (a
portion of Pol), protease (a portion of Pol), Env, gp120, gp140 or gp160, gp41, Nef, Vif, Vpr,
Vpu, Rev, Tat and immunogenic derivatives thereof and immunogenic fragments thereof,
particularly Env, Gag, Nef and Pol and immunogenic derivatives thereof and immunogenic
fragments thereof including p17, p24, RT and integrase. HIV vaccines may comprise
polypeptides and/or polynucleotides encoding polypeptides corresponding to multiple different
HIV antigens for example 2 or 3 or 4 or more HIV antigens which may be selected from the
above list. Several different antigens may, for example, be comprised in a single fusion protein.
More than one first immunogenic polypeptide and/or more than one second immunogenic
polypeptide each of which is an HIV antigen or a fusion of more than one antigen may be
employed.
For example an antigen may comprise Gag or an immunogenic derivative or
immunogenic fragment thereof, fused to RT or an immunogenic derivative or immunogenic
fragment thereof, fused to Nef or an immunogenic derivative or immunogenic fragment thereof
wherein the Gag portion of the fusion protein is present at the 5' terminus end of the
polypeptide.
A Gag sequence of use according to the invention may exclude the Gag p6 polypeptide
encoding sequence. A particular example of a Gag sequence for use in the invention
comprises p17 and/or p24 encoding sequences.
A RT sequence may contain a mutation to substantially inactivate any reverse
transcriptase activity (see WO03/025003).
The RT gene is a component of the bigger pol gene in the HIV genome. It will be
understood that the RT sequence employed according to the invention may be present in the
context of Pol, or a fragment of Pol corresponding at least to RT. Such fragments of Pol retain
major CTL epitopes of Pol. In one specific example, RT is included as just the p51 or just the
p66 fragment of RT.
The RT component of the fusion protein or composition according to the invention
optionally comprises a mutation to remove a site which serves as an internal initiation site in
prokaryotic expression systems.
Optionally the Nef sequence for use in the invention is truncated to remove the
sequence encoding the N terminal region i.e. removal of from 30 to 85 amino acids, for example
from 60 to 85 amino acids, particularly the N terminal 65 amino acids (the latter truncation is
referred to herein as trNef). Alternatively or additionally the Nef may be modified to remove the
myristylation site. For example the Gly 2 myristylation site may be removed by deletion or
substitution. Alternatively or additionally the Nef may be modified to alter the dileucine motif of
Leu 174 and Leu 175 by deletion or substitution of one or both leucines. The importance of the
dileucine motif in CD4 downregulation is described e.g. in Bresnahan P.A. et al (1998) Current
Biology, 8(22): 1235-8.
The Env antigen may be present in its full length as gp160 or truncated as gp140 or
shorter (optionally with a suitable mutation to destroy the cleavage site motif between gp120
and gp41). The Env antigen may also be present in its naturally occurring processed form as
gp120 and gp41. These two derivatives of gp160 may be used individually or together as a
combination. The aforementioned Env antigens may further exhibit deletions (in particular of
variable loops) and truncations. Fragments of Env may be used as well.
An exemplary gp120 sequence is shown in SEQ ID No 8. An exemplary gp140
sequence is shown in SEQ ID No 6.
Immunogenic polypeptides according to the invention may comprise Gag, Pol, Env and
Nef wherein at least 75%, or at least 90% or at least 95%, for example, 96% of the CTL
epitopes of these native antigens are present.
In immunogenic polypeptides according to the invention which comprise p17/p24 Gag,
p66 RT, and truncated Nef as defined above, 96% of the CTL epitopes of the native Gag, Pol
and Nef antigens are suitably present.
One embodiment of the invention provides an immunogenic polypeptide containing p17,
p24 Gag, p66 RT , truncated Nef (devoid of nucleotides encoding terminal amino-acids 1-85 -
"trNef") in the order Gag, RT, Nef. In polynucleotides encoding immunogenic polypeptides of
the invention, suitably the P24 Gag and P66 RT are codon optimized.
Specific polynucleotide constructs and corresponding polypeptide antigens according to
the invention include:
1. p17, p24 (codon optimised) Gag - p66 RT (codon optimised) - truncated Nef;
2. truncated Nef - p66 RT (codon optimised) - p17, p24 (codon optimised) Gag;
3. truncated Nef - p17, p24 (codon optimised) Gag - p66 RT (codon optimised);
4. p66 RT (codon optimised) - p17, p24 (codon optimised) Gag - truncated Nef;
5. p66 RT (codon optimised) - truncated Nef - p17, p24 (codon optimised) Gag;
6. p17, p24 (codon optimised) Gag - truncated Nef - p66 RT (codon optimised).
An exemplary fusion is a fusion of Gag, RT and Nef particularly in the order Gag-RT-Nef
(see eg SEQ ID No 2). Another exemplary fusion is a fusion of p17, p24, RT and Nef
particularly in the order p24-RT-Nef-p17 (see eg SEQ ID No 16, referred to elsewhere herein as
"F4").
In another embodiment an immunogenic polypeptide contains Gag, RT, integrase and
Nef, especially in the order Gag-RT-integrase-Nef (see eg SEQ ID No 4).
In other embodiments the HIV antigen may be a fusion polypeptide which comprises Nef
or an immunogenic derivative thereof or an immunogenic fragment thereof, and p17 Gag and/or
p24 Gag or immunogenic derivatives thereof or immunogenic fragments thereof, wherein when
both p17 and p24 Gag are present there is at least one HIV antigen or immunogenic fragment
between them.
For example, Nef is suitably full length Nef.
For example p17 Gag and p24 Gag are suitably full length p17 and p24 respectively.
In one embodiment an immunogenic polypeptide comprises both p17 and p24 Gag or
immunogenic fragments thereof. In such a construct the p24 Gag component and p17 Gag
component are separated by at least one further HIV antigen or immunogenic fragment, such as
Nef and/or RT or immunogenic derivatives thereof or immunogenic fragments thereof. See
WO2006/013106 for further details.
In fusion proteins which comprise p24 and RT, it may be preferable that the p24
precedes the RT in the construct because when the antigens are expressed alone in E coli
better expression of p24 than of RT is observed.
Some constructs according to the invention include the following:

* represents RT methionine592 mutation to lysine
In another aspect the present invention provides a fusion protein of HIV antigens
comprising at least four HIV antigens or immunogenic fragments, wherein the four antigens or
fragments are or are derived from Nef, Pol and Gag. Preferably Gag is present as two separate
components which are separated by at least one other antigen in the fusion. Preferably the Nef
is full length Nef. Preferably the Pol is p66 or p51RT. Preferably the Gag is p17 and p24 Gag.
Other preferred features and properties of the antigen components of the fusion in this aspect of
the invention are as described herein.
Preferred embodiments of this aspect of the invention are the four component fusions as
already listed above:

The immunogenic polypeptides of the present invention may have linker sequences
present in between the sequences corresponding to particular antigens such as Gag, RT and
Nef. Such linker sequences may be, for example, up to 20 amino acids in length. In a particular
example they may be from 1 to 10 amino acids, or from 1 to 6 amino acids, for example 4-6
amino acids.
Further description of such suitable HIV antigens can be found in WO03/025003.
HIV antigens of the present invention may be derived from any HIV clade, for example
clade A, clade B or clade C. For example the HIV antigens may be derived from clade A or B,
especially B.
In one specific embodiment of the invention, a first immunogenic polypeptide is a
polypeptide comprising Gag and/or Pol and/or Nef or a fragment or derivative of any of them (eg
p24-RT-Nef-p17). In one specific embodiment of the invention a second immunogenic
polypeptide is a polypeptide comprising Gap and/or Pol and/or Nef or a fragment or derivative of
any of them (eg Gag-RT-Nef or Gag-RT-integrase-Nef).
Thus in one specific embodiment, a polypeptide comprising Gap and/or Pol and/or Nef
or a fragment or derivative of any of them (eg p24-RT-Nef-p17) is a first immunogenic
polypeptide and a polypeptide comprising Gap and/or Pol and/or Nef or a fragment or derivative
of any of them (eg Gag-RT-Nef or Gag-RT-integrase-Nef) is a second immunogenic
polypeptide.
In another specific embodiment of the invention, a first immunogenic polypeptide is Env
or a fragment or derivative thereof eg gp120, gp140 or gp160 (especially gp120). In one
specific embodiment of the invention a second immunogenic polypeptide is a polypeptide
comprising Gag and/or Pol and/or Nef or a fragment or derivative of any of them (eg p24-RT-
Nef-p17).
Thus in one specific embodiment, Env or a fragment or derivative thereof eg gpl20,
gp140 or gp160 (especially gp120) is a first immunogenic polypeptide and a polypeptide
comprising Gag and/or Pol and/or Nef or a fragment or derivative of any of them (eg p24-RT-
Nef-p17) is a second immunogenic polypeptide.
In another specific embodiment of the invention, a first immunogenic polypeptide is a
polypeptide comprising Gag and/or Pol and/or Nef or a fragment or derivative of any of them (eg
p24-RT-Nef-p17). In one specific embodiment of the invention a second immunogenic
polypeptide is Env or a fragment or derivative thereof eg gp120, gp140 or gp160 (especially
gp120).
Thus in one specific embodiment, a polypeptide comprising Gag and/or Pol and/or Nef
or a fragment or derivative of any of them (eg p24-RT-Nef-p17) is a first immunogenic
polypeptide and Env or a fragment or derivative thereof eg gp120, gp140 or gp160 (especially
gp120) is a second immunogenic polypeptide.
Immunogenic derivatives and immunogenic fragments of antigens
The aforementioned antigens may be employed in the form of immunogenic derivatives
or immunogenic fragments thereof rather than the whole antigen.
As used herein the term "immunogenic derivative" in relation to an antigen of native
origin refers to an antigen that have been modified in a limited way relative to its native
counterparts. For example it may include a point mutation which may change the properties of
the protein eg by improving expression in prokaryotic systems or by removing undesirable
activity, eg enzymatic activity. Immunogenic derivatives will however be sufficiently similar to the
native antigens such that they retain their antigenic properties and remain capable of raising an
immune response against the native antigen. Whether or not a given derivative raises such an
immune response may be measured by a suitably immunological assay such as an ELISA (for
antibody responses) or flow cytometry using suitable staining for cellular markers (for cellular
responses).
Immunogenic fragments are fragments which encode at least one epitope, for example a
CTL epitope, typically a peptide of at least 8 amino acids. Fragments of at least 8, for example
8-10 amino acids or up to 20, 50, 60, 70, 100, 150 or 200 amino acids in length are considered
to fall within the scope of the invention as long as the polypeptide demonstrates antigenicity,
that is to say that the major epitopes (eg CTL epitopes)are retained by the polypeptide.
Adenovirus
Adenoviral vectors of the present invention comprise one or more heterologous
polynucleotides (DNA) which encode one or more immunogenic polypeptides.
Adenoviral vectors of use in the present invention may be derived from a range of
mammalian hosts.
Adenoviruses (herein referred to as "Ad" or "Adv") have a characteristic morphology with
an icosohedral capsid consisting of three major proteins, hexon (II), penton base (III) and a
knobbed fibre (IV), along with a number of other minor proteins, VI, VIII, IX, Ilia and IVa2
(Russell W.C. 2000, Gen Viriol, 81:2573-2604). The virus genome is a linear, double-stranded
DNA with a terminal protein attached covalently to the 5" termini, which have inverted terminal
repeats (ITRs). The virus DNA is intimately associated with the highly basic protein VII and a
small peptide termed mu. Another protein, V, is packaged with this DNA-protein complex and
provides a structural link to the capsid via protein VI. The virus also contains a virus-encoded
protease, which is necessary for processing of some of the structural proteins to produce
mature infectious virus.
Over 100 distinct serotypes of adenovirus have been isolated which infect various
mammalian species, 51 of which are of human origin. Thus one or more of the adenoviral
vectors may be derived from a human adenovirus. Examples of such human-derived
adenoviruses are Ad1, Ad2, Ad4, Ad5, Ad6, Ad11, Ad 24, Ad34, Ad35, particularly Ad5, Ad11
and Ad35. The human serotypes have been categorised into six subgenera (A-F) based on a
number of biological, chemical, immunological and structural criteria.
Although Ad5-based vectors have been used extensively in a number of gene therapy
trials, there may be limitations on the use of Ad5 and other group C adenoviral vectors due to
preexisting immunity in the general population due to natural infection. Ad5 and other group C
members tend to be among the most seroprevalent serotypes. Immunity to existing vectors may
develop as a result of exposure to the vector during treatment. These types of preexisting or
developed immunity to seroprevalent vectors may limit the effectiveness of gene therapy or
vaccination efforts. Alternative adenovirus serotypes, thus constitute very important targets in
the pursuit of gene delivery systems capable of evading the host immune response.
One such area of alternative serotypes are those derived from non human primates,
especially chimpanzee adenoviruses. See US Patent 6,083,716 which describes the genome of
two chimpanzee adenoviruses.
It has been shown that chimpanzee ("Pan" or "C") adenoviral vectors induce strong
immune responses to transgene products as efficiently as human adenoviral vectors (Fitzgerald
etal. J. Immunol. 170:1416).
Non human primate adenoviruses can be isolated from the mesenteric lymph nodes of
chimpanzees. Chimpanzee adenoviruses are sufficiently similar to human adenovirus subtype
C to allow replication of E1 deleted virus in HEK 293 cells. Yet chimpanzee adenoviruses are
phylogenetically distinct from the more common human serotypes (Ad2 and Ad5). Pan 6 is less
closely related to and is serologically distinct from Pans 5, 7 and 9.
Thus one or more of the adenoviral vectors may be derived from a non-human primate
adenovirus eg a chimpanzee adenovirus such as one selected from serotypes Pan5, Pan6,
Pan7 and Pan9.
Adenoviral vectors may also be derived from more than one adenovirus serotype, and
each serotype may be from the same or different source. For example they may be derived
from more than one human serotype and/or more than one non-human primate serotype.
Methods for constructing chimeric adenoviral vectors are disclosed in WO2005/001103.
There are certain size restrictions associated with inserting heterologous DNA into
adenoviruses. Human adenoviruses have the ability to package up to 105% of the wild type
genome length (Bett et al 1993, J Virol 67 (10), 5911-21). The lower packaging limit for human
adenoviruses has been shown to be 75% of the wild type genome length (Parks et al 1995, J
Virol 71(4), 3293-8).
One example of adenoviruses of use in the present invention are adenoviruses which
are distinct from prevalent naturally occurring serotypes in the human population such as Ad2
and Ad5. This avoids the induction of potent immune responses against the vector which limits
the efficacy of subsequent administrations of the same serotype by blocking vector uptake
through neutralizing antibody and influencing toxicity.
Thus, the adenovirus may be an adenovirus which is not a prevalent naturally occurring
human virus serotype. Adenoviruses isolated from animals have immunologically distinct
capsid, hexon, penton and fibre components but are phylogenetically closely related.
Specifically, the virus may be a non-human adenovirus, such as a simian adenovirus and in
particular a chimpanzee adenovirus such as Pan 5, 6, 7 or 9. Examples of such strains are
described in WO03/000283 and are available from the American Type Culture Collection, 10801
University Boulevard, Manassas, Virginia 20110-2209, and other sources. Desirable
chimpanzee adenovirus strains are Pan 5 [ATCC VR-591], Pan 6 [ATCC VR-592], and Pan 7
[ATCC VR-593].
Use of chimpanzee adenoviruses is thought to be advantageous over use of human
adenovirus serotypes because of the lack of pre-existing immunity, in particular the lack of
cross-neutralising antibodies, to adenoviruses in the target population. Cross-reaction of the
chimpanzee adenoviruses with pre-existing neutralizing antibody responses is only present in
2% of the target population compared with 35% in the case of certain candidate human
adenovirus vectors. The chimpanzee adenoviruses are distinct from the more common human
subtypes Ad2 and Ad5, but are more closely related to human Ad4 of subgroup E, which is not
a prevalent subtype. Pan 6 is less closely related to Pan 5, 7 and 9.
The adenovirus of the invention may be replication defective. This means that it has a
reduced ability to replicate in non-complementing cells, compared to the wild type virus. This
may be brought about by mutating the virus e.g. by deleting a gene involved in replication, for
example deletion of the E1a, E1b, E3 or E4 gene.
The adenoviral vectors in accordance with the present invention may be derived from
replication defective adenovirus comprising a functional E1 deletion. Thus the adenoviral
vectors according to the invention may be replication defective due to the absence of the ability
to express adenoviral E1a and E1b, i.e., are functionally deleted in E1a and E1b. The
recombinant adenoviruses may also bear functional deletions in other genes [see WO
03/000283] for example, deletions in E3 or E4 genes. The adenovirus delayed early gene E3
may be eliminated from the adenovirus sequence which forms part of the recombinant virus.
The function of E3 is not necessary to the production of the recombinant adenovirus particle.
Thus, it is unnecessary to replace the function of this gene product in order to package a
recombinant adenovirus useful in the invention. In one particular embodiment the recombinant
adenoviruses have functionally deleted E1 and E3 genes. The construction of such vectors is
described in Roy et al., Human Gene Therapy 15:519-530, 2004.
Recombinant adenoviruses may also be constructed having a functional deletion of the
E4 gene, although it may be desirable to retain the E4 ORF6 function. Adenovirus vectors
according to the invention may also contain a deletion in the delayed early gene E2a. Deletions
may also be made in any of the late genes L1 through to L5 of the adenovirus genome.
Similarly deletions in the intermediate genes IX and IVa may be useful.
Other deletions may be made in the other structural or non-structural adenovirus genes.
The above deletions may be used individually, i.e. an adenovirus sequence for use in the
present invention may contain deletions of E1 only. Alternatively, deletions of entire genes or
portions thereof effective to destroy their biological activity may be used in any combination. For
example in one exemplary vector, the adenovirus sequences may have deletions of the E1
genes and the E4 gene, or of the E1, E2a and E3 genes, or of the E1 and E3 genes (such as
functional deletions in E1a and E1b, and a deletion of at least part of E3), or of the E1, E2a and
E4 genes, with or without deletion of E3 and so on. Such deletions may be partial or full
deletions of these genes and may be used in combination with other mutations, such as
temperature sensitive mutations to achieve a desired result.
The adenoviral vectors can be produced on any suitable cell line in which the virus is
capable of replication. In particular, complementing cell lines which provide the factors missing
from the viral vector that result in its impaired replication characteristics (such as E1 and/or E4)
can be used. Without limitation, such a cell line may be HeLa [ATCC Accession No. CCL 2],
A549 [ATCC Accession No. CCL 185], HEK 293, KB [CCL 17], Detroit [e.g., Detroit 510, CCL
72] and WI-38 [CCL 75] cells, among others. These cell lines are all available from the
American Type Culture Collection, 10801 University Boulevard, Manassas, Virginia 20110-
2209. Other suitable parent cell lines may be obtained from other sources, such as PER.C6©
cells, as represented by the cells deposited under ECACC no. 96022940 at the European
Collection of Animal Cell Cultures (ECACC) at the Centre for Applied Microbiology and
Research (CAMR, UK) or Her 96 cells (Crucell).
The polynucleotide sequences which encode immunogenic polypeptides may be
codon optimised for mammalian cells. Such codon-optimisation is described in detail in
WO05/025614. Codon optimization for certain HIV sequences is further described in WO
03/025003.
In one embodiment of the present invention the polynucleotide constructs comprise an
N-terminal leader sequence. The signal sequence, transmembrane domain and cytoplasmic
domain are individually all optionally present or deleted. In one embodiment of the present
invention all these regions are present but modified.
A promoter for use in the adenoviral vector according to the invention may be the
promoter from HCMV IE gene, for example wherein the 5' untranslated region of the HCMV IE
gene comprising exon 1 is included and intron A is completely or partially excluded as described
in WO 02/36792.
When several antigens are fused into a fusion protein, such protein would be encoded
by a polynucleotide under the control of a single promoter.
In an alternative embodiment of the invention, several antigens may be expressed
separately through individual promoters, each of said promoters may be the same or different.
In yet another embodiment of the invention some of the antigens may form a fusion, linked to a
first promoter and other antigen(s) may be linked to a second promoter, which may be the same
or different from the first promoter.
Thus, the adenoviral vector may comprise one or more expression cassettes each of
which encode one antigen under the control of one promoter. Alternatively or additionally it may
comprise one or more expression cassettes each of which encode more than one antigen under
the control of one promoter, which antigens are thereby expressed as a fusion. Each
expression cassette may be present in more than one locus in the adenoviral vector.
The polynucleotide or polynucleotides encoding immunogenic polypeptides to be
expressed may be inserted into any of the adenovirus deleted regions, for example into the E1
deleted region.
Although two or more polynucleotides encoding immunogenic polypeptides may be
linked as a fusion, the resulting protein may be expressed as a fusion protein, or it may be
expressed as separate protein products, or it may be expressed as a fusion protein and then
subsequently broken down into smaller subunits.
Adjuvant
Adjuvants are described in general in Vaccine Design - the Subunit and Adjuvant
Approach eg Powell and Newman, Plenum Press, New York, 1995.
Suitable adjuvants include an aluminium salt such as aluminium hydroxide or aluminium
phosphate, but may also be a salt of calcium, iron or zinc, or may be an insoluble suspension of
acylated tyrosine, or acylated sugars, cationically or anionically derivatised polysaccharides, or
polyphosphazenes.
In the formulation of the invention it is preferred that the adjuvant composition preferentially
induces a Th1 response. However it will be understood that other responses, including other
humoral responses, are not excluded.
It is known that certain vaccine adjuvants are particularly suited to the stimulation of either
Th1 orTh2 - type cytokine responses. Traditionally the best indicators of the Th1:Th2 balance of
the immune response after a vaccination or infection includes direct measurement of the
production of Th1 or Th2 cytokines by T lymphocytes in vitro after restimulation with antigen,
and/or the measurement of the lgG1 :lgG2a ratio of antigen specific antibody responses.
Thus, a Th1-type adjuvant is one which stimulates isolated T-cell populations to produce
high levels of Th1-type cytokines in vivo (as measured in the serum) or ex vivo (cytokines that
are measured when the cells are re-stimulated with antigen in vitro), and induces antigen
specific immunoglobulin responses associated with Th1-type isotype.
Preferred Th1-type immunostimulants which may be formulated to produce adjuvants
suitable for use in the present invention include and are not restricted to the following:
The Toll like receptor (TLR) 4 ligands, especially an agonist such as a lipid A derivative
particularly monophosphoryl lipid A or more particularly 3 Deacylated monophoshoryl lipid A (3
D - MPL).
3 D -MPL is sold under the trademark MPL® by GlaxoSmithKline and primarily
promotes CD4+ T cell responses characterized by the production of IFN-g (Th1 cells i.e. CD4 T
helper cells with a type-1 phenotype). It can be produced according to the methods disclosed in
GB 2 220 211 A. Chemically it is a mixture of 3-deacylated monophosphoryl lipid A with 3,4, 5
or 6 acylated chains. Preferably in the compositions of the present invention small particle 3 D-
MPL is used. Small particle 3 D -MPL has a particle size such that it may be sterile-filtered
through a 0.22(xm filter. Such preparations are described in International Patent Application No.
W094/21292. Synthetic derivatives of lipid A are known and thought to be TLR 4 agonists
including, but not limited to:
OM174(2-deoxy-6-o-[2-deoxy-2-[(R)-3-dodecanoyloxytetra-decanoylamino]-4-o-
phosphono-p-D-glucopyranosyl]-2-[(R)-3-hydroxytetradecanoylamino]-a-D-
glucopyranosyldihydrogenphosphate), (WO 95/14026)
OM 294 DP (3S, 9 R) -3--[(R)-dodecanoyloxytetradecanoylamino]-4-oxo-5-aza-9(R)-
[(R)-3-hydroxytetradecanoylamino]decan-1,10-diol,1,10-bis(dihydrogenophosphate)(WO99
/64301 and WO 00/0462 )
OM 197 MP-Ac DP (3S-, 9R) -3-[(R) -dodecanoyloxytetradecanoylamino]-4-oxo-5-aza-9-
[(R>3-hydroxytetradecanoylamino]decan-1,10-diol,1 -dihydrogenophosphate 10-(6-
aminohexanoate) (WO 01/46127)
Other TLR4 ligands which may be used are alkyl Glucosaminide phosphates (AGPs)
such as those disclosed in WO9850399 or US6303347 (processes for preparation of AGPs are
also disclosed), or pharmaceutically acceptable salts of AGPs as disclosed in US6764840.
Some AGPs are TLR4 agonists, and some are TLR4 antagonists. Both are thought to be useful
as adjuvants.
Saponins are also preferred Th1 immunostimulants in accordance with the invention.
Saponins are well known adjuvants and are taught in: Lacaille-Dubois, M and Wagner H. (1996.
A review of the biological and pharmacological activities of saponins. Phytomedicine vol 2 pp
363-386). For example, Quil A (derived from the bark of the South American tree Quillaja
Saponaria Molina), and fractions thereof, are described in US 5,057,540 and "Saponins as
vaccine adjuvants", Kensil, C. R., Crit Rev Ther Drug Carrier Syst, 1996,12 (1-2):1-55; and EP
0 362 279 B1. The haemolytic saponins QS21 and QS 17 (HPLC purified fractions of Quil A)
have been described as potent systemic adjuvants, and the method of their production is
disclosed in US Patent No. 5,057,540 and EP 0 362 279 B1. Also described in these references
is the use of QS7 (a non-haemolytic fraction of Quil-A) which acts as a potent adjuvant for
systemic vaccines. Use of QS21 is further described in Kensil etal. (1991. J. Immunology vol
146, 431-437). Combinations of QS21 and polysorbate or cyclodextrin are also known (WO
99/10008). Particulate adjuvant systems comprising fractions of QuilA, such as QS21 and QS7
are described in WO 96/33739 and WO 96/11711. One such system is known as an Iscom and
may contain one or more saponins.
The adjuvant of the present invention may in particular comprises a Toll like receptor
(TLR) 4 ligand, especially 3D-MPL, in combination with a saponin.
Other suitable adjuvants include TLR 9 ligands (agonists). Thus another preferred
immunostimulant is an immunostimulatory oligonucleotide containing unmethylated CpG
dinucleotides ("CpG"). CpG is an abbreviation for cytosine-guanosine dinucleotide motifs
present in DNA. CpG is known in the art as being an adjuvant when administered by both
systemic and mucosal routes (WO 96/02555, EP 468520, Davis ef a/., J.lmmunol, 1998,
160(2):870-876; McCluskie and Davis, J.lmmunol., 1998, 161(9):4463-6). Historically, it was
observed that the DNA fraction of BCG could exert an anti-tumour effect. In further studies,
synthetic oligonucleotides derived from BCG gene sequences were shown to be capable of
inducing immunostimulatory effects (both in vitro and in vivo). The authors of these studies
concluded that certain palindromic sequences, including a central CG motif, carried this activity.
The central role of the CG motif in immunostimulation was later elucidated in a publication by
Krieg, Nature 374, p546 1995. Detailed analysis has shown that the CG motif has to be in a
certain sequence context, and that such sequences are common in bacterial DNA but are rare
in vertebrate DNA. The immunostimulatory sequence is often: Purine, Purine, C, G, pyrimidine,
pyrimidine; wherein the CG motif is not methylated, but other unmethylated CpG sequences are
known to be immunostimulatory and may be used in the present invention.
In certain combinations of the six nucleotides a palindromic sequence is present.
Several of these motifs, either as repeats of one motif or a combination of different motifs, can
be present in the same oligonucleotide. The presence of one or more of these
immunostimulatory sequences containing oligonucleotides can activate various immune
subsets, including natural killer cells (which produce interferon 7 and have cytolytic activity) and
macrophages (Wooldrige et ai Vol 89 (no. 8), 1977). Other unmethylated CpG containing
sequences not having this consensus sequence have also now been shown to be
immunomodulatory.
CpG when formulated into vaccines, is generally administered in free solution together
with free antigen (WO 96/02555; McCluskie and Davis, supra) or covalently conjugated to an
antigen (WO 98/16247), or formulated with a carrier such as aluminium hydroxide ((Hepatitis
surface antigen) Davis et al. supra ; Brazolot-Millan etal., Proc.Natl.Acad.Sci., USA, 1998,
95(26), 15553-8).
Other TLR9 agonists of potential interest include immunostimulatory CpR motif
containing oligonucleotides and YpG motif containing oligonucleotides (Idera).
Such immunostimulants as described above may be formulated together with carriers,
such as for example liposomes, oil in water emulsions, and or metallic salts, including
aluminium salts (such as aluminium hydroxide). For example, 3D-MPL may be formulated with
aluminium hydroxide (EP 0 689 454) or oil in water emulsions (WO 95/17210); QS21 may be
advantageously formulated with cholesterol containing liposomes (WO 96/33739), oil in water
emulsions (WO 95/17210) or alum (WO 98/15287); CpG may be formulated with alum (Davis et
al. supra ; Brazolot-Millan supra) or with other cationic carriers.
Combinations of immunostimulants are also preferred, in particular a combination of a
monophosphoryl lipid A and a saponin derivative (WO 94/00153; WO 95/17210; WO 96/33739;
WO 98/56414; WO 99/12565; WO 99/11241), more particularly the combination of QS21 and
3D-MPL as disclosed in WO 94/00153. Alternatively, a combination of CpG plus a saponin
such as QS21 also forms a potent adjuvant for use in the present invention. Alternatively the
saponin may be formulated in a liposome or in an Iscorn and combined with an
immunostimulatory oligonucleotide.
Thus, suitable adjuvant systems include, for example, a combination of monophosphoryl
lipid A, preferably 3D-MPL, together with an aluminium salt (eg as described in WO00/23105).
An enhanced system involves the combination of a monophosphoryl lipid A and a
saponin derivative particularly the combination of QS21 and 3D-MPL as disclosed in WO
94/00153, or a less reactogenic composition where the QS21 is quenched in cholesterol
containing liposomes (DQ) as disclosed in WO 96/33739. This combination may additionally
comprise an immunostimulatory oligonucleotide.
Thus an example adjuvant comprises QS21 and/or MPL and/or CpG.
A particularly potent adjuvant formulation involving QS21, 3D-MPL & tocopherol in an oil
in water emulsion is described in WO 95/17210 and is another preferred formulation for use in
the invention.
Another preferred formulation comprises a CpG oligonucleotide alone or together with
an aluminium salt.
In a further aspect of the present invention there is provided a method of manufacture
of a vaccine formulation as herein described, wherein the method comprises admixing one or
more first immunogenic polypeptides according to the invention with a suitable adjuvant.
Particularly preferred adjuvants for use in the formulations according to the invention
are as follows:
i) 3D-MPL + QS21 in a liposome (see eg Adjuvant B below)
Preferably, the adjuvant is presented in the form of a liposome, ISCOM or an oil-in-water
emulsion. In one example embodiment of the invention the adjuvant comprises an oil-in-water
emulsion. In another example embodiment of the invention the adjuvant comprises liposomes.
Suitably the adjuvant component does not contain any virus. Thus suitably, compositions
for use according to the invention do not contain any virus other than the one or more more
adenoviral vectors comprising one or more heterologous polynucleotides encoding one or more
second immunogenic polypeptides derived from a pathogen.
Compositions, dosage and administration
In methods of the invention, the immunogenic polypeptide(s), the adenoviral vector(s)
and the adjuvant are administered concomitantly.
Typically the adjuvant will be co-formulated with an immunogenic polypeptide. Suitably
the adjuvant will also be co-formulated with any other immunogenic polypeptide to be
administered.
Thus in one embodiment of the invention there is provided a method of raising an
immune response which comprises administering (i) one or more first immunogenic
polypeptides co-formulated with an adjuvant; and (ii) one or more adenoviral vectors comprising
one or more heterologous polynucleotides encoding one or more second immunogenic
polypeptides; wherein one or more first immunogenic polypeptides and adjuvant, and one or
more adenoviral vectors are administered concomitantly.
By "co-formulated" is meant that the first immunogenic polypeptide and the adjuvant are
contained within the same composition eg a pharmaceutical composition.
Typically the adenoviral vector is contained in a composition eg a pharmaceutical
composition.
Alternatively, the one or more first immunogenic polypeptides, the one or more
adenoviral vectors and an adjuvant are co-formulated.
Thus, there are provided compositions according to the invention which comprise one or
more immunogenic polypeptides, one or more adenoviral vectors, and an adjuvant.
Compositions and methods according to the invention may involve use of more than one
immunogenic polypeptide and/or more than one adenoviral vector. Use of multiple antigens is
especially advantageous in raising protective immune responses to certain pathogens, such as
HIV, M. tuberculosis and Plasmodium sp. Compositions according to the invention may
comprise more than one adjuvant.
Compositions and methods employed according to the invention may typically comprise
a carrier eg an aqueous buffered carrier. Protective components such as sugars may be
included.
Compositions should be administered in sufficient amounts to transduce the target cells
and to provide sufficient levels of gene transfer and expression and to permit pathogen-specific
immune responses to develop thereby to provide a prophylactic or therapeutic benefit without
undue adverse or with medically acceptable physiological effects, which can be determined by
those skilled in the medical arts. Conventional and pharmaceutically acceptable routes of
administration include, but are not limited to, direct delivery to the retina and other intraocular
delivery methods, direct delivery to the liver, inhalation, intranasal, intravenous, intramuscular,
intratracheal, subcutaneous, intradermal, epidermal, rectal, oral and other parenteral routes of
administration. Routes of administration may be combined, if desired, or adjusted depending
upon the gene product or the condition. The route of administration primarily will depend on the
nature of the condition being treated. Most suitably the route is intramuscular, intradermal or
epidermal.
Preferred tissues to target are muscle, skin and mucous membranes. Skin and mucous
membranes are the physiological sites where most infectious antigens are normally
encountered.
When the first immunogenic polypeptide, adjuvant and adenoviral vector are not co-
formulated, the different formulations (eg polypeptide/adjuvant and adenoviral vector
formulations) may be administered by the same route of administration or by different routes of
administration.
Dosages of compositions in the methods will depend primarily on factors such as the
condition being treated, the age, weight and health of the subject, and may thus vary among
subjects. For example, a therapeutically effective adult human or veterinary dosage is generally
in the range of from about 100 p.L to about 100 rnL of a carrier containing concentrations of from
about 1 x 106 to about 1 x 1015 particles, about 1 x 1011 to 1 x 1013 particles, or about 1 x 109 to
1x 1012 particles of virus together with around 1-1000ug, or about 2-1 OOug eg around 4-40ug
immunogenic polypeptide. Dosages will range depending upon the size of the animal and the
route of administration. For example, a suitable human or veterinary dosage (for about an 80
kg animal) for intramuscular injection is in the range of about 1 x 109 to about 5 x 1012 virus
particles and 4-40 ug protein per ml_, for a single site. One of skill in the art may adjust these
doses, depending on the route of administration, and the therapeutic or vaccinal application for
which the composition is employed.
The amount of adjuvant will depend on the nature of the adjuvant and the immunogenic
polypeptide, the condition being treated and the age, weight and health of the subject. Typically
for human administration an amount of adjuvant of 1-100ug eg 10-50 ug per dose may be
suitable.
Suitably an adequate immune response is achieved by a single concomitant
administration of the composition or compositions of the invention in methods of the invention.
However if the immune response is further enhanced by administration of a further dose of first
immunogenic polypeptide, adjuvant and adenoviral vector on a second or subsequent occasion
(for example after a month or two months) then such a protocol is embraced by the invention.
We have found that good pathogen-specific CD4+ and/or CD8+ T-cell responses may
typically be raised after a single concomitant administration of the composition or compositions
of the invention in methods of the invention. However we have found that good pathogen-
specific antibody responses may require a second or further concomitant administration of the
composition or compositions of the invention.
The components of the invention may be combined or formulated with any suitable
pharmaceutical excipient such as water, buffers and the like.
Examples
Adjuvant preparations
1) The preparation of oil in water emulsion followed the protocol as set forth In WO
95/17210.
The emulsion contains: 42.72 mg/ml squalene, 47.44 mg/ml tocopherol, 19.4 mg/ml Tween 80.
The resulting oil droplets have a size of approximately 180 nm
Tween 80 was dissolved in phosphate buffered saline (PBS) to give a 2% solution in the PBS.
To provide 100 ml two fold concentrate, emulsion 5g of DL alpha tocopherol and 5ml of
squalene were vortexed until mixed thoroughly. 90ml of PBS/Tween solution was added and
mixed thoroughly. The resulting emulsion was then passed through a syringe and finally
microfluidised by using an M110S microfluidics machine. The resulting oil droplets have a size
of approximately 180 nm
2) Preparation of oil in water emulsion with QS21 and MPL
Sterile bulk emulsion was added to PBS to reach a final concentration of 500 ul of emulsion per
ml (v/v). 3 D-MPL was then added. QS21 was then added Between each addition of
component, the intermediate product was stirred for 5 minutes. Fifteen minutes later, the pH
was checked and adjusted if necessary to 6.8 +/- 0.1 with NaOH or HCI. The final concentration
of 3D-MPL and QS21 was 100 ug per ml for each.
3) Preparation of liposomal MPL
A mixture of lipid (such as phosphatidylcholine either from egg-yolk or synthetic) and cholesterol
and 3 D-MPL in organic solvent, was dried down under vacuum (or alternatively under a stream
of inert gas). An aqueous solution (such as phosphate buffered saline) was then added, and
the vessel agitated until all the lipid was in suspension. This suspension was then microfluidised
until the liposome size was reduced to about 100 nm, and then sterile filtered through a 0.2 urn
filter. Extrusion or sonication could replace this step.
Typically the cholesterol: phosphatidylcholine ratio was 1:4 (w/w), and the aqueous solution was
added to give a final cholesterol concentration of 10 mg/ml.
The final concentration of MPL is 2 mg/ml.
The liposomes have a size of approximately 100 nm and are referred to as SUV (for small
unilamelar vesicles). The liposomes by themselves are stable over time and have no fusogenic
capacity.
4) Preparation of Adjuvant B ("adj B")
Sterile bulk of SUV was added to PBS. PBS composition was Na2HPO4: 9 mM; KH2PO4: 48
mM; NaCI: 100 mM pH 6.1. QS21 in aqueous solution was added to the SUV. The final
concentration of 3D-MPL and QS21 was 100 ug per ml for each. This mixture is referred as
Adjuvant B. Between each addition of component, the intermediate product was stirred for 5
minutes. The pH was checked and adjusted if necessary to 6.1 +/- 0.1 with NaOH or HCI.
Preparation of p24-RT-Nef-P17 protein ("F4")
F4 was prepared as described in WO2006/013106 Example 1, codon-optimised method.
Preparation of Chimp adenovirus Pan7 containing Gaq-RT-Nef transqene ("Pan7GRN'")
Construction of Gag, RT, Nef plasmid.
Plasmid p73i-Tgrn
The full sequence of the Tgm plasmid insert is given in SEQ ID No 1 and the plasmid
construction shown graphically in Fig 1. This contains p17 p24 (codon optimised) Gag, p66 RT
(codon optimised and inactivated) and truncated Nef.
The plasmid P73i-Tgrn was prepared as described in WO03/025003 Examples 1-13.
Construction of the E1/E3 deleted Pan 7 Adenovirus
The E1/E3 deleted Pan 7 Adenovirus was prepared as described in WO2006/120034 Example
1.
Other serotypes of vectors can be constructed in a similar way. A full description of the
construction of E1, E3 and E4 deletions in this and other Pan Adenovirus serotypes is given in
WO03/0046124. Further information is also available in Human Gene Therapy 15:519-530.
Insertion of Gag, RT, Nef sequence into Adenovirus
Using plasmid P73i-Tgrn, the GRN expression cassette was inserted into E1/E3 deleted Pan 7
adenovirus to produce C7-GRNc as described in WO2006/120034 Example 3. C7-GRNc is the
Pan7GRN adenovirus component used in the examples set out herein.
Example 1
Immunogenicitv study in mice immunised with adenovirus component (Pan7GRN) and protein
component (F4/adiuvant B) separately or with both adenovirus and protein components co-
formulated together
The mouse strain used was CB6F1 and 3 mice were used per timepoint. For immunisation with
F4/adjuvant B (P), 1/10 of the human dose was injected i.e. 9 ug of F4 protein in 50uL of
adjuvant B. For immunisation with Pan7GRN (A), 10 x 108 virus particles in 50uL of saline (0.9%
NaCI water for injection solution) was used. The Pan7GRN chimp adenovirus carries the genes
coding for Gag (G), RT (R) and Nef (N).

Thus it can be seen that in groups 1 and 2, the mice were immunized with 2 injections of protein
(PP) or adenovirus (AA), respectively. Mice from groups 3 and 4, received a conventional prime-
boost schedule: protein then adenovirus (PPAA) or the other way round (AAPP) whereas in
groups 5 and 6, the mice received one or two injections of a combination (combo) of protein and
adenovirus together according to the invention. Mice from group 7 only received adjuvant
control whereas mice from group 6 were naive.
The following read-outs were performed:
Antibody responses (ELISA performed on the sera from each individual animals from each
group):
-antibody response against F4 (Figure 4)
-antibody response against F4 components p24, RT, Nef and p17 (Figure 5-8)
Cellular responses (Figures 2-3):
-measured by flow cytometry following surface and intracellular cytokine staining after overnight
restimulation of spleen cells with pools of peptides of p24, RT, Nef or p17. The spleen cells of 3
mice per timepoint and per group were pooled for the analysis.
For groups 1 and 2, samples were taken for measurement 21 days after the corresponding final
immunisation. For the remaining groups, measurements were taken 21 days, 56 days and 112
days after the corresponding final immunisation.
Results:
The results are shown in Figures 2-8.
The X axis labels correspond as follows:
PP - Group 1 animals following second immunisation
AA - Group 2 animals following second immunisation
PPAA - Group 3 animals following fourth immunisation
AAPP - Group 4 animals following fourth immunisation
Combo - Group 5 animals following immunisation
Combo x 2 - Group 6 animals following second immunisation
The measurement timepoints (21, 56 or 112 days post last immunisation) are indicated in
parentheses.
Cellular responses (Figure 2-3):
At the timepoints analysed, the data show that CD4+ T-cell responses were observed mainly
against p24, RT and Nef.
As shown in Figures 2a and 2b (left panels), 21 days post last immunisation, the highest CD4+
T-cell responses are observed with two immunisations of adenovirus followed by two
immunisations of protein/adjuvant (Group 4 animals). One injection of the combination of
adenovirus/protein/adjuvant induces higher CD4+ T-cell levels than two injections of
protein/adjuvant following restimulation with p24, RT or Nef peptides.
For restimulation by RT and Nef, two immunisations with the combination of
adenovirus/protein/adjuvant induces a CD4+ T-cell response slightly higher than with one
immunisation with the combination, whereas the responses with one or two immunisations were
identical for p24.
At the timepoints analysed, the CD8+ T-cell responses are mainly observed against the p24 and
RT peptides, and no significant numbers of CD8+ T-cells specific for Nef or p17 were detected.
As shown in Figures 2a and 2b (right panels), 21 days post last immunisation CD8+ T-cell
responses were similar after one or two immunisations with the combination of
adenovirus/protein/adjuvant. The CD8 response against p24 observed in groups immunised
either (i) twice with adenovirus or (ii) twice with adenovirus followed by twice with protein or (iii)
once or twice with the combination of adenovirus/protein/adjuvant were comparable to each
other and slightly lower than the one from the group immunised twice with protein followed by
twice with adenovirus. The CD8 response against RT observed in groups immunised once or
twice with the combination of adenovirus/protein/adjuvant were comparable and slightly lower to
the one from the groups immunised either (i) twice with adenovirus or (ii) twice with adenovirus
followed by twice with protein or (iii) twice with protein followed by twice with adenovirus.
The CD4 and CD8 T cell responses were also analysed at later timepoints (56 and 112 days
post last immunisation), when persistence of the responses can be determined (Figures 3a and
3b). The CD4 responses (Fig 3a and 3b, left panels) are mainly observed against p24, RT and
Nef. At these timepoints, the highest CD4 responses are observed in the animals immunised
twice with adenovirus followed by twice with protein. The CD4 response in mice immunised
once or twice with the combination of adenovirus/protein/adjuvant were comparable to each
other and generally higher than the response observed in groups immunised twice with protein
followed by twice with adenovirus.
At the later timepoints, the CD8 response against p24 is the highest in the group immunised
once with the combination of adenovirus/protein/adjuvant (Fig 3b, right panel). It is comparable
to the one from animals immunised twice with protein followed by twice with adenovirus and
slightly higher than the one from the animals immunised either (i) twice with the combination of
adenovirus/protein/adjuvant or (ii) twice with adenovirus followed by twice with protein. The
latter two are comparable between each other. The CD8 response against RT is the highest
and similar in groups immunised (i) twice with the combination of adenovirus/protein/adjuvant or
(ii) twice with adenovirus followed by twice with protein. The CD8 response against RT from
groups immunised (i) twice with the combination of adenovirus/protein/adjuvant or (ii) twice with
protein followed by twice with adenovirus was slightly lower but comparable between each other
(Figure 3). As shown in figure 3a (right panel), no significant numbers of CD8+ T-cells specific
for Nef or p17 were detected.
Antibody responses:
As shown in Figures 4 to 8, the antibody responses detected are mainly directed against p24
(Fig 5), RT (Fig 6) and Nef (Fig 8). The anti-F4 (Fig 4) response generally mimics the response
observed against each of the p24, RT or Nef components and can be characterized as follows:
- Low to no antibody response is detected in groups immunised (i) twice with adenovirus
or (ii) once with the combination of adenovirus/protein/adjuvant;
- The highest antibody responses usually detected in group immunised twice with the
protein at 21days post immunisation. However, it is also in this group that the highest
variability between individuals is observed. In addition, for the anti-Nef serology, the
group immunised twice with adenovirus followed by twice with protein appears to display
the highest response, when compared to the other groups;
- The response observed in groups immunised (i)) twice with the combination of
adenovirus/protein/adjuvant or (ii) twice with protein followed by twice with adenovirus or
(iii) twice with adenovirus followed by twice with protein are comparable, peak at 21 days
post last immunisation and then slightly decrease over time.
Antibody responses against p17 (Fig 7) were very low to undetectable in all groups.
Conclusion:
Globally, the highest antigen-specific cell-mediated immune response is observed in the AAPP
treatment group after 4 immunisations. However, when comparing groups after 2 immunisations
(i.e. AA, PP and 2xcombo groups), the induction of both antigen-specific CD4 and CD8 T cell
responses is only observed in the group immunised twice with the protein/adenovirus/adjuvant
combination. In addition, similar levels of CD4 and CD8 T cell responses can be reached after a
single injection of the protein/adenovirus/adjuvant combination. Moreover, in terms of
persistence, the antigen-specific T cell responses observed 112 days after the 2nd immunisation
with the protein/adenovirus/adjuvant combination are comparable to the ones observed 112
days after the 4th immunisations in the AAPP treatment group. Finally, it appears that 2
immunisations with the protein/adenovirus/adjuvant combination are needed to obtain an
antibody response comparable to the one obtained in the group immunised twice with the
adjuvanted protein, group that provided the highest antibody responses in general.
Example 2
Immunoqenicitv study in mice immunised with Pan7GRN adenovirus and F4 protein/adiuvant B
co-formulated together
The mouse strain used was CB6F1 with 9 mice per group. Mice were immunized once with a
co-formulation of the F4 protein (1/10 of the human dose was injected i.e. 9 ug) together with 10
x 108 virus particles of Pan7GRN, in 50uL of adjuvant B or a dilution of the latter (1/2, 1/4 or
1/10). The CD4 and CD8 cellular responses against a pool of either Nef, p17, p24 or RT
peptides were determined 21 days post immunization (3 pools of 3 spleens for each group).
The following read-out was performed:
Cellular responses (Figure 9):
-measured by flow cytometry following surface and intracellular cytokine staining after overnight
restimulation of spleen cells with pools of peptides of p24, RT, Nef or p17. The spleen cells
were pooled (3 pools of 3 spleens per group) for the analysis.
Results:
The results shown in Figure 9 represent the cellular responses observed after restimulation with
a pool of p24 or RT peptides.
The X axis labels correspond as follows:
Adj B - Mice immunised with 9ugF4/ 108vpPan7GRN/ non-diluted adjuvant B
1/2 Adj B- Mice immunised with 9ugF4/ 108vpPan7GRN/ adjuvant B diluted 1/2
1/4 Adj B- Mice immunised with 9u.gF4/ 108vpPan7GRN/ adjuvant B diluted 1/4
1/10 Adj B - Mice immunised with 9ugF4/ 108vpPan7GRN/ adjuvant B diluted 1/10
Naive - Naive mice (no immunisation)
The results indicate that CD4 (Figure 9, left panel) and CD8 (Figure 9, right panel) responses
are mainly observed against p24 and RT, with the CD8 T cell response specific to RT being
lower than the one specific to p24. In addition, the results indicate that the CD4 responses
against p24 and RT at 21 days post-immunisations in the groups immunised with the non-
diluted adjuvant B or a 1/2 dilution of it are similar. These CD4 responses tend to decrease
when the adjuvant is diluted 1/4. When the adjuvant B is diluted at 1/10, the CD4 responses
observed are similar to the ones from groups immunised with the 1/4 dilution of the adjuvant B.
The anti-CD8 responses against p24 are comparable whether the adjuvant is diluted 1/2 or not.
However, the response decreases when the adjuvant B is diluted 1/4 and even more so if it is
diluted 1/10. In contrast, such trends are not seen for the anti-RT CD8 responses where there is
not a real dose range effect of the dose of adjuvant used.
Conclusion:
CD4+ cells and CD8+ cells against F4 components were induced by a single administration of a
composition containing an immunogenic polypeptide, an adenoviral vector containing a
heterologous polynucleotide encoding an immunogenic polypeptide and an adjuvant, even
when the latter was diluted. The impact of adjuvant dilution differed depending on the antigen-
specific CD4 or CD8 responses of interest. In particular the highest responses observed were
against p24 and the anti-p24 CD4 and CD8 T cell responses show a dose range effect
correlating with the dose of adjuvant used in the combination vaccine. While the same effect
can be observed for the anti-RT CD4 T cell response, the dose range effect of the dose of
adjuvant used in the combo is less clear for the anti-RT CD8 T cell response. Finally, if we
consider the global antigen-specific CD4 and CD8 T cell responses and sum the responses
against the 4 antigens, a dose range can be observed.
Example 3:
Immunooenicitv study in New Zealand white rabbits immunised with Pan7GRN or F4/adjuvant
B sequentially or with both adenovirus and protein components co-formulated together
For immunisation with F4/adjuvant B, the human dose was injected i.e. 90 ug of F4 protein in
500uL of adjuvant B. For immunisation with Pan7GRN, 10 x 1010 or 10 x 1012 virus particles in
500uL of saline were used. For the immunization with both adenovirus and protein components
co-formulated together, 90ug of F4 protein, 10 x 1011 virus particles of Pan7 GRN in 500uL of
adjuvant B were used.
The vaccination schedule was as follows:

There were 3 rabbits per group except for group 1 which included only 2 rabbits.
The following read-outs were performed:
Antibody responses (ELISA performed on the sera from each individual animals from each
group):
-antibody response against F4
-antibody response against F4 components p24, RT, Nef and p17
Lymphoproliferative responses:
The lymphoproliferation was determined by the uptake of tritiated thymidine by peripheral blood
mononuclear cells (isolated from whole blood after a density gradient) restimulated in vitro with
pools of Nef, p17, p24 and/or RT peptides for 88 hours in the presence of tritiated thymidine for
the last 16 hours of the incubation.
Results:
Lymphoproliferative response:
As shown in Figure 10, the highest lymphoproliferative responses are observed in the group
immunised twice with protein. The lymphoproliferative response from animals immunised twice
with the combination of adenovirus/protein/adjuvant was observed in all rabbits from the group.
It actually peaked after one injection and could be further recalled (at similar levels than after
the 1st injection) following a third injection of the combination of adenovirus/protein/adjuvant,
suggesting that the first two injections did not induce a neutralizing response that would inhibit
any response to a further similar injection. In its intensity, the proliferative response observed in
rabbits immunised with the combination of adenovirus/protein/adjuvant was comparable to the
one observed in animals immunised once or twice with 1012 viral particles of adenovirus and
appeared higher than the one from animals immunised once or twice with 1010 viral particles of
adenovirus. Altogether, this suggests that using the combination of adenovirus/protein/adjuvant
could decrease the dose of adenovirus to be used. Finally, after a third injection of the
combination of adenovirus/protein/adjuvant, the response observed in group 4 was similar to
the one from animals immunised 3 times with the protein (group 1).
Serology:
As shown in Figure 11, the kinetic of the anti-F4 antibody response observed in the animals
immunised twice with the combination of adenovirus/protein/adjuvant is similar to the one from
animals immunised twice with the protein: it is already detected at 7 days post-2nd injection and
then decrease over time. However, in terms of intensity, the anti-F4 response of animals
immunised twice with the combination of adenovirus/protein/adjuvant remains higher at later
timepoints (21 and 63 days post-2nd immunisation) when compared to the anti-F4 response
from animals immunised twice with the protein. No anti-F4 antibody response is observed in
rabbits immunised once with 1010 viral particles of adenovirus. In rabbits immunised once with
1012 viral particles of adenovirus, an anti-F4 response is only detected at 21 and 63 days post-
immunisation. In that group, the high variability of the response observed at the 63 day post-
immunisation timepoint (d77) results from a single animal (out of the 3) displaying higher titers
against the different F4 components, especially p24 and RT as shown in Figures 12a and 12b
respectively. The anti-F4 antibody response is mainly composed of antibodies targeting p24 and
RT and to a much lesser extent Nef and p17.
Conclusion:
Lymphoproliferative and antibody responses could be induced in rabbits after two injections of a
composition containing an immunogenic polypeptide, an adenoviral vector containing a
heterologous polynucleotide encoding an immunogenic polypeptide and an adjuvant. In
addition, we have evidence that a lymphoproliferative response can be recalled after a third
injection of such composition. Finally, the best antibody response (in intensity and persistence)
is observed with the adenovirus/protein/adjuvant combination.
Example 4
Immunogenicity of F4 (codon optimized)/adjuvant B and C7-GRN when administrated as
a combination in CB6F1 mice.
Experimental design
CB6F1 mice were immunized twice (days 0 and 21) with different combinations listed below.
F4co/ adjuvant B was used at 9µg F4co/animal in 50ul AdjuvantB (1/10 human dose) and the
C7-GRN virus at 10a viral particles/animal. F4co in Example 4 is F4 prepared as described in
WO2006/013106 Example 1, codon-optimised method.

Schedule of immunizations and immune response analysis
Immunisations were carried out at day 0 and day 21. Intracellular cytokine staining (ICS) was
carried out at 21 days, 28 days (7 days post immunisation 2), 42 days (21 days post
immunisation 2), and 77 days (56 days post immunisation 2).
Results
HlV-specific CD4 T cell responses
The results are shown in the following figures:
Figure 13. Quantification of HIV-1-specific CD4 T cells. The % of CD3 CD4 T cells secreting
IFN-y and/or IL-2 is represented for each protocol of immunization at four time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering F4 sequence and the cytokine production was
measured by ICS. Each value is the geometric mean of 5 pools of 3 mice.
Figure 14. Distribution of the frequency of F4-specific CD4 T cells 7 days after two
immunizations. The frequency of F4-specific circulating CD4 T cells at 7 days after two
immunizations is represented for each protocol. Each dot represents the value obtained for one
pool of 3 mice.
Figure 15. Cytokine production of F4-specific CD4 T cells 7 days after two immunizations. The
% of F4-specific CD4 T cells secreting IL-2 and/or IFN-y is represented for 5 pools of 3 mice.
Results for the immunization with F4co/ adjuvant B (A), F4co/ adjuvant B /C7 empty (B) and
F4co/ adjuvant B /C7-GRN (C) are presented.
The frequency of F4-specific circulating CD4 T cells reaches 2.82% 21 days after two
immunizations with the F4co/ adjuvant B combination and declines to 0.91% 56 days post-
immunization (Figure 13). Two doses of the C7-GRN virus alone result in 0.52% of F4-specific
circulating CD4 T cells 21 days post last immunization and the presence of the adjuvant
adjuvant B does not alter this response.
The presence of the empty vector C7 or the recombinant C7-GRN virus in addition of the F4co/
adjuvant B mix does not increase nor interfere with the frequency of F4-specific CD4 T cell
response (3.58% and 2.82% respectively, 21 days post-last immunization). Even if no statistical
analysis has been performed, the population distribution suggests that the intensity of the F4-
specific CD4 T cell responses is not different between the three protocols F4co/ adjuvant B,
F4co/ adjuvant B /C7 empty and F4co/ adjuvant B /C7-GRN (Figure 14).
As expected, administration of the F4co without adjuvant B does not induce significant F4-
specific CD4 T cells.
The profile of cytokine production shows that after immunization with F4co/ adjuvant B, the F4-
specific CD4 T cells secrete both IFN-y and IL-2. Addition of C7empty or C7-GRN in the
immunization protocol does not alter this profile.
As a result, these data suggest that the greatest F4-specific CD4 T cell response is obtained
after immunization with the F4co/ adjuvant B combination and that the presence of the C7-GRN
virus does not improve nor alter this response.
Antigen-specific CD8 T cell responses
The results are shown in the following figures
Figure 16. Quantification of HIV-1-specific CD8 T cells. The % of CD3 CD8 T cells secreting
IFN-y and/or IL-2 is represented for each protocol of immunization at four time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of Brefeldin then
overnight) with a pool of peptides covering F4 and the cytokine production was measured by
ICS. Each value is the geometric mean of 5 pools of 3 mice.
Figure 17. Cytokine production of F4-specific CD8 T cells 7 days after two immunizations. The
% of F4-specific CD8 T cells secreting IL-2 and/or IFN-y is represented for 5 pools of 3 mice.
Results for the immunization with C7-GRN (A), C7-GRN/ adjuvant B (B) and C7-GRN+F4co/
adjuvant B (C) are presented.
After one injection, the recombinant vector C7-GRN induces a high frequency of F4-specific
circulating CD8 T cells (9,70% of total CD8 T cells, 21 days post-immunization) (Figure 4). A
second injection does not boost the F4-specific CD8 T cell response. The F4co/ adjuvant B
combination induces low to undetectable F4-specific CD8 T cells and adding this combination to
the C7-GRN does not improve or impair the F4-specific CD8 T cell response.
The F4-specific CD8 T cell response is delayed when the adjuvant B is added to the C7-GRN,
but reaches the same level as with the C7-GRN alone or the C7-GRN/F4co/ adjuvant B
combination at 21 days post-second immunization.
The F4-specific CD8 T cells mainly secrete IFN-y whether the C7-GRN vector is injected alone
or in combination with F4co/ adjuvant B (Figure 17).
Interestingly, the F4-specific CD8 T cell response persists up to 56 days post-last immunization
without declining, suggesting that the C7 vector elicits high and persistent CD8 T cells.
Conclusions
The F4co/adjuvant B vaccine induces a high frequency of poly-functional HIV-specific CD4 T
cells but no HIV-specific CD8 T cells in CB6F1 mice. In the same animal model, the
recombinant adenovirus C7 expressing Gag, RT and Nef (Ad C7-GRN) induces a high antigen-
specific CD8 T cell response and low to undetectable antigen-specific CD4 T cells. A
combination of F4/ adjuvant B and Ad C7-GRN elicits both antigen-specific CD4 and CD8 T
cells at the same time. A combination of three components, F4co, adjuvantB and C7-GRN
elicts the highest levels of both antigen specific CD4 and CD8 T cells at the same time.
Combining F4/ adjuvant B and Ad C7-GRN has an additive effect concerning the intensity of
both arms of the cellular immune response. The effect of the antigen-specific CD4 T cell
response on the functionality of antigen-specific CD8 T cell response remains to be determined
in this model.
Example 5
Immunogenicity of the chimpadenovirus C7 expressing CS2 construct of CSP protein
from Plasmodium falciparum (C7-CS2) when administered alone
Experimental design:
CB6F1 mice were immunized once intramuscularly with a dose range (1010, 109 & 108 viral
particles) of the C7 chimpadenovirus expressing the CSP malaria antigen and the CSP-specific
(C-term and N-term) CD4 and CD8 T cell responses were determined 21, 28 and 35 days post-
injection by ICS (Intra-cellular Cytokine Staining).
CSP-specific CD4 T cell responses
The results are shown in the following figures:
Figure 18. Quantification of CSP-specific CD4 T cells. The % of CD4 T cells secreting IFN-y
and/or IL-2 is represented for each protocol of immunization at three time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering CSP N-term or CSP C-term sequences and the
cytokine production was measured by ICS. The responses to the C-term and N-term peptide
pools were added up and each value is the average of 5 pools of 4 mice.
Figure 19. Quantification of CSP-specific CD8 T cells. The % of CD8 T cells secreting IFN-y
and/or IL-2 is represented for each protocol of immunization at three time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering CSP N-term or CSP C-term sequences and the
cytokine production was measured by ICS. The responses to the C-term and N-term peptide
pools were added up and each value is the average of 5 pools of 4 mice.
These results indicate that both 1010 and 109 doses of C7-CS2 elicit similar levels of CSP-
specific CD4 T cell responses (peak 0.5%) and similar levels of CSP-specific CD8 T cell
responses (peak 8%). The dose of 1010 of C7-CS2 was chosen in subsequent experiments
where the immunogenicity of C7-CS2 in combination with RTS.S was tested (see below).
Example 6
Immunogenicity of C7-CS2 and RTS.S when administered as a combination in CB6F1
mice
Experimental design:
CB6F1 mice were immunized three times intramuscularly (day 0, 14 & 28) with either a
combination of the malaria vaccine candidate RTS,S (5ug) in 50ul of Adjuvant B (referred as P-
P-P in the figures below) or a combination of RTS.S (5ug) and C7-CS2(101C viral particles) in
50ul of Adjuvant B (referred as C-C-C in the figures below). The CSP-specific (C-term and N-
term) CD4 and CD8 T cell responses were determined at the following time-points:
- 7 days post 2 immunizations
-7,21, 35 and 49 days post 3 immunizations
CSP-specific T cell responses were determined by ICS (Intra-cellular Cytokine Staining).
The CSP-specific antibody responses in the sera from immunized animals were also
determined by ELISA at 14 and 42 days post- 3rd immunization.
CSP-specific CD4 T cell responses
The results are shown in the following figures:
Figure 20. Quantification of CSP(N-term)-specific CD4 T cells. The % of CD4 T cells secreting
IFN-y and/or IL-2 is represented for each protocol of immunization at five time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering the CSP N-term sequence and the cytokine
production (IFNg and/or IL-2) was measured by ICS. Each value is the average of 4 pools of 7
mice.
Figure 21. Quantification of CSP(C-term)-specific CD4 T cells. The % of CD4 T cells secreting
IFN-y and/or IL-2 is represented for each protocol of immunization at five time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering the CSP C-term sequence and the cytokine
production (IFNg and/or IL-2) was measured by ICS. Each value is the average of 4 pools of 7
mice.
These results indicate that mice immunized with 3 injections of the combination [RTS.S + C7-
CS2 1010 +Adjuvant B] display higher antigen-specific CD4 T cell responses (both against the
C-term and N-term part of CSP) than the mice immunized with 3 injections of RTS.S+Adjuvant
B.
CSP-specific CD8 T cell responses
The results are shown in the following figures:
Figure 22. Quantification of CSP(N-term)-specific CD8 T cells. The % of CD8 T cells secreting
IFN-y and/or IL-2 is represented for each protocol of immunization at five time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering the CSP N-term sequence and the cytokine
production (IFNg and/or IL-2) was measured by ICS. Each value is the average of 4 pools of 7
mice.
Figure 23. Quantification of CSP(C-term)-specific CD8 T cells. The % of CD8 T cells secreting
IFN-y and/or IL-2 is represented for each protocol of immunization at five time-points. Peripheral
blood lymphocytes (PBLs) were stimulated ex vivo (2 hours before addition of the Brefeldin then
overnight) with a pool of peptides covering the CSP C-term sequence and the cytokine
production (IFNg and/or IL-2) was measured by ICS. Each value is the average of 4 pools of 7
mice.
These results indicate that mice immunized with 3 injections of the combination [RTS,S + C7-
CS2 1010 + Adjuvant B ] display higher antigen-specific CD8 T cell responses (both against the
C-term and N-term part of CSP) than the mice immunized with 3 injections of RTS,S+Adjuvant
B.
CSP-specific antibody responses
The results are shown in the following figure:
Figure 24. Quantification of CSP-specific antibody titers.The sera from the mice were collected
at 14 and 42 days post 3rd immunization. The anti-CSP antibody titers were measured in each
of these individual sera by ELISA. The data shown is the geometric mean antibody titers + 95%
confidence interval.
These results indicate that mice immunized with 3 injections of the combination [RTS.S + C7-
CS2 1010 + Adjuvant B ] display similar CSP-specific antibody titers than the mice immunized
with 3 injections of RTS.S+Adjuvant B.
Conclusions
The RTS.S/adjuvant B vaccine induces a high frequency of CSP C-term-specific CD4 T cells
but no CSP N-term specific CD4 T cells. In addition, the RTS.S/adjuvant B vaccine induces low
to undetectable CSP C& N-term specific CD8 T cells. In the same animal model, the
recombinant adenovirus C7 expressing CSP induces high CSP(C-term and N-term)-specific
CD8 T cell responses and lower CSP(C-term and N-term)-specific CD4 T cell responses. A
combination of RTS,S/ adjuvant B and Ad C7-CS2 elicits high levels of both CSP(C-term and N-
term)-specific CD4 and CD8 T cells at the same time. Combining RTS.S/ adjuvant B and Ad C7-
CS2 has an additive effect concerning the intensity of both arms of the T cell response. Finally,
the combination of RTS,S/ adjuvant B and Ad C7-CS2 elicits high levels of CSP-specific
antibody responses that are comparable to the ones induced by RTS.S/adjuvant B.
All references referred to in this application, including patent and patent applications, are
incorporated herein by reference to the fullest extent possible.
Throughout the specification and the claims which follow, unless the context requires otherwise,
the word 'comprise', and variations such as 'comprises' and 'comprising', will be understood to
imply the inclusion of a stated integer, step, group of integers or group of steps but not to the
exclusion of any other integer, step, group of integers or group of steps.
The application of which this description and claims forms part may be used as a basis for
priority in respect of any subsequent application. The claims of such subsequent application
may be directed to any feature or combination of features described herein. They may take the
form of product, composition, process, or use claims and may include, by way of example and
without limitation, the following claims:
Claims
1. A method of raising an immune response against a pathogen which comprises
administering (i) one or more first immunogenic polypeptides derived from said pathogen; (ii)
one or more adenoviral vectors comprising one or more heterologous polynucleotides encoding
one or more second immunogenic polypeptides derived from said pathogen; and (iii) an
adjuvant; wherein the one or more first immunogenic polypeptides, the one or more adenoviral
vectors and the adjuvant are administered concomitantly.
2. A method of raising an immune response against a pathogen which comprises
administering (i) one or more first immunogenic polypeptides derived from said pathogen co-
formulated with an adjuvant; and (ii) one or more adenoviral vectors comprising one or more
heterologous polynucleotides encoding one or more second immunogenic polypeptides derived
from said pathogen; wherein one or more immunogenic polypeptides and adjuvant, and one or
more adenoviral vectors are administered concomitantly.
3 A method of stimulating the production of pathogen-specific CD4+ and/or CD8+ T-cells
and/or antibodies in mammals which comprises administering to said mammal (i) one or more
first immunogenic polypeptides derived from a pathogen; (ii) one or more adenoviral vectors
comprising one or more heterologous polynucleotides encoding one or more second
immunogenic polypeptides derived from said pathogen; and (iii) an adjuvant; wherein the one or
more first immunogenic polypeptides, the one or more adenoviral vectors and the adjuvant are
administered concomitantly, for example by administering an immunologically effective amount
of an aforeseaid composition.
4. A method of raising an immune response against a pathogen which consists of (a)
administering (i) one or more first immunogenic polypeptides derived from said pathogen; (ii)
one or more adenoviral vectors comprising one or more heterologous polynucleotides encoding
one or more second immunogenic polypeptides derived from said pathogen; and (iii) an
adjuvant; wherein the one or more immunogenic polypeptide, the one or more adenoviral vector
and the adjuvant are administered concomitantly; and (b) optionally repeating the steps of (a).
5. A method of raising an immune response against a pathogen which comprises
administering (i) one or more first immunogenic polypeptides derived from said pathogen; (ii)
one or more adenoviral vectors comprising one or more heterologous polynucleotides encoding
one or more second immunogenic polypeptides derived from said pathogen; and (iii) an
adjuvant; wherein the one or more first immunogenic polypeptides, the one or more adenoviral
vectors and the adjuvant are administered concomitantly; and wherein the method does not
involve administering any priming dose of immunogenic polypeptide or polynucleotide encoding
immunogenic polypeptide.
6. A method according to any one of claims 1 to 5 wherein one or more immunogenic
polypeptides, one or more adenoviral vectors and an adjuvant are co-formulated.
7. A method according to any one of claims 1 to 6 wherein production of pathogen specific
CD4+ T-cells and CD8+ T-cells and antibodies is stimulated.
8. A vaccine composition comprising (i) one or more first immunogenic polypeptides
derived from a pathogen; (ii) one or more adenoviral vectors comprising one or more
heterologous polynucleotide encoding one or more second immunogenic polypeptides derived
from said pathogen; and (iii) an adjuvant.
9. A method or vaccine composition according to any one of claims 1 to 8 wherein one or
more of said one or more first immunogenic polypeptides is substantially the same as one or
more of said one or more second immunogenic polypeptides.
10. A method or vaccine composition according to any one of claims 1 to 8 wherein one or
more of said one or more first immunogenic polypeptides contains at least one antigen which is
substantially the same as an antigen contained in one or more of said one or more second
immunogenic polypeptides.
11. A method or vaccine composition according to any one of claims 1 to 10 wherein one or
more the first immunogenic polypeptides comprises at least one T cell epitope.
12. A method or vaccine composition according to any one of claims 1 to 11 wherein the one
or more first immunogenic polypeptide comprises at least one B cell epitope.
13. A method or vaccine composition according to any one of claims 1 to 12 wherein one or
more of said one or more first immunogenic polypeptides and one or more of said one or more
second immunogenic polypeptides share one or more identical B-cell and/or T-cell epitopes.
14. A method or vaccine composition according to any one of claims 1 to 8 wherein none of
the one or more of said one or more first immunogenic polypeptides is substantially the same as
or contains any antigen in common with one or more of said one or more second immunogenic
polypeptides.
15. A method or vaccine composition according to any one of claims 1 to 14 wherein one or
more of the adenoviral vectors is derived from a human adenovirus.
16. A method or vaccine composition according to claim 15 wherein the human adenovirus
serotype is selected from Ad1, Ad2, Ad4, Ad5, Ad6, Ad11, Ad 24, Ad34 and Ad35.
17. A method or vaccine composition according to any one of claims 1 to 14 wherein one or
more of the adenoviral vectors is derived from a non-human primate adenovirus.
18. A method or vaccine composition according to claim 17 wherein the non-human primate
adenovirus serotype is selected from chimpanzee adenovirus serotypes Pan5, Pan6, Pan7 and
Pan9.
19. A method or vaccine composition according to any one of claims 1 to 18 wherein the
pathogen is HIV.
20. A method or vaccine composition according to claim 19 wherein the immunogenic
polypeptides contain HIV derived antigens which are selected from Env, Nef, Gag, and Pol and
immunogenic derivatives thereof and immunogenic fragments thereof.
21. A method or vaccine composition according to claim 20 wherein a first immunogenic
polypeptide is p24-RT-Nef-p17.
22. A method or vaccine composition according to claim 20 or claim 21 wherein a second
immunogenic polypeptide is Gag-RT-Nef.
23. A method or vaccine composition according to any one of claims 1 to 18 wherein the
pathogen is Plasmodium falciparum and/or Plasmodium vivax.
24. A method or vaccine composition according to claim 23 wherein the immunogenic
polypeptides contain antigens derived from Plasmodium falciparum and/or Plasmodium vivax
which are selected from circumsporozoite (CS) protein, MSP-1, MSP-3, AMA-1, LSA-1, LSA-3
and immunogenic derivatives thereof or immunogenic fragments thereof.
25. A method or vaccine composition according to claim 24 wherein a/the immunogenic
polypeptide is the hybrid protein RTS.
26. A method or vaccine composition according to claim 25 wherein RTS is presented in the
form of a mixed particle known as RTS.S.
27. A method or vaccine composition according to any one of claims 24 to 26 wherein a/the
immunogenic polypeptide encoded by a polynucleotide is the CS protein from Plasmodium
falciparum or immunogenic fragment thereof.
28. A method or vaccine composition according to any one of claims 1 to18 wherein the
pathogen is Mycobacterium tuberculosis.
29. A method or vaccine composition according to any one of claims 1 to 28 wherein the
adjuvant comprises a preferential stimulator of Th1 responses.
30. A method or vaccine composition according to claim 29 wherein the adjuvant comprises
QS21 and/or 3D-MPL and/or CpG.
31. A method or vaccine composition according to claim 30 wherein the adjuvant comprises
QS21 and 3D-MPL.
32. A method or vaccine composition according to any one of claims 1 to 31 wherein the
adjuvant contains an oil-in-water emulsion.
33. A method or vaccine composition according to any one of claims 1 to 31 wherein the
adjuvant contains liposomes.
34. A method of stimulating an immune response in a mammal which comprises
administering to a subject an immunologically effective amount of a vaccine composition
according to any one of claims 8 to 33.
35. Use of a vaccine composition according to any one of claim 8 to 33 in the manufacture
of a medicament for stimulating an immune response in a mammal.
36. A vaccine composition according to any one of claims 8 to 33 for use in stimulating an
immune response in a mammal.
37. A kit comprising (i) one or more first immunogenic polypeptides derived from a
pathogen; (ii) one or more adenoviral vectors comprising one or more heterologous
polynucleotides encoding one or more second immunogenic polypeptides derived from said
pathogen; and (iii) an adjuvant.
38. A kit comprising (i) one or more first immunogenic polypeptides derived from a
pathogen and an adjuvant; and (ii) one or more second adenoviral vectors comprising one or
more heterologous polynucleotides encoding one or more immunogenic polypeptides derived
from said pathogen.
39. A method, or vaccine, or kit, or use according to any preceding claim wherein the first
immunogenic polypeptide comprises p24-RT-Nef-pl7, the adjuvant comprises 3D-MPL and
QS21 in a liposome such as adjuvant B herein, and the adenoviral vector comprises a
chimpanzee adenovirus serotype Pan7 vector comprising a polynucleotide encoding the
immunogenic polypeptide Gag-RT-Nef, optionally codon optimised.
40 A method, or vaccine, or kit, or use according to any preceding claim wherein one, or
two, or all of the polypeptide, adenoviral vector and adjuvant components are combined with a
pharmaceutically acceptable excipient.


The present invention relates to, inter alia, a method of raising an immune response against a pathogen which comprises administering (i) one or more first immunogenic polypeptides derived from said pathogen; (ii) one or more adenoviral vectors comprising one or more heterologous polynucleotides encoding one or more second immunogenic polypeptides derived from said
pathogen; and (iii) an adjuvant; wherein the one or more first immunogenic polypeptides, the one or more adenoviral vectors and the adjuvant are administered concomitantly. The invention also relates to vaccines, pharmaceutical compositions, kits and uses employing said polypeptides, adenoviral vectors and adjuvants.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=ocFunEx1jAm3+6gYrhB3Eg==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 271732
Indian Patent Application Number 3402/KOLNP/2009
PG Journal Number 10/2016
Publication Date 04-Mar-2016
Grant Date 02-Mar-2016
Date of Filing 29-Sep-2009
Name of Patentee GLAXOSMITHKLINE BIOLOGICALS S.A.
Applicant Address RUE DE L'INSTITUT 89, B-1330 RIXENSART BELGIUM
Inventors:
# Inventor's Name Inventor's Address
1 VOSS, GERALD HERMANN GLAXOSMITHKLINE BIOLOGICALS S.A., RUE DE L'INSTITUT 89, B-1330 RIXENSART BELGIUM
PCT International Classification Number C07K 14/16
PCT International Application Number PCT/EP2008/052448
PCT International Filing date 2008-02-28
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/892,714 2007-03-02 U.S.A.