Field of Technology

The present invention provides peptides mixtures comprising a first, second and third peptide, wherein the first peptide is a peptide of TGFPR2 having a frameshift mutation, the second peptide is a peptide of ASTE1 having a frameshift mutation and the third peptide is a peptide of TAFip having a frameshift mutation, and wherein each peptide is capable of eliciting an immune response. The present invention also provides a peptide of TAFip having a frameshift mutation and being capable of eliciting an immune response, T-cells and T-cell receptors specific for such peptides, T-cell mixtures comprising T-cells specific for such peptides, at least one nucleic acid molecule encoding one or more of the peptides, vectors comprising the nucleic acid molecule and host cells comprising the vector. The present invention further provides pharmaceutical formulations comprising such peptides, peptide mixtures, T-cells, T-cell mixtures, at least one nucleic acid molecule, vectors or host cells, uses of such peptides, peptide mixtures, T-cell receptors, T-cells and T-cell mixtures for the prophylaxis and/or treatment of cancer, and methods of selecting peptides, peptide mixtures, T-cell receptors, T- cells, and T-cell mixtures for the treatment of cancer.

Background

DNA microsatellites are strings of repetitive DNA, in which certain DNA motifs (nucleotide seguence patterns) are repeated, usually about 5 to 50 times. Microsatellite instability (MSI) is a change in the number of repeats of microsatellites and can be caused by impaired DNA mismatch repair (MMR) enzyme activity.

MMR corrects errors that occur spontaneously during DNA replication, such as single base mismatches or short insertions or deletions. When MMR activity is impaired, these spontaneous errors are not repaired, and this can result in microsatellite instability (i.e. a change in the number of repeats) and frameshift mutations in the DNA microsatellite seguences.

Frameshift mutations are the addition or deletion of one or two base pairs from a gene, resulting in different codons, and, therefore, a different protein being encoded, from the point of mutation. The frameshift typically results in truncated protein seguences because a STOP codon occurs prematurely, and the encoded proteins are usually defective or inactive.

In recent years, immuno-oncology has been a developing field, with efforts focussed on using the patient’s own immune system to fight cancer. However, one problem is that antibodies can only bind to tumour antigens that are exposed on the surface of tumour cells. For this reason the efforts to produce a cancer treatment based on the immune system of the body has been less successful than expected.

Several proteins have been identified as frequently having frameshift mutations in MSI-H cancers. For example, TGFPR2 (SEQ ID NO: 1) is a growth factor, and its interaction with TGFp mediates control of cell growth. Frameshift mutations in TGFPR2 render it biologically nonfunctional, thereby inducing uncontrolled cell growth and cancer progression. Frameshift mutations are also found in ASTE1 (SEQ ID NO: 4) and TAFip (SEQ ID NO: 6), and single nucleotide deletions in the genes encoding these proteins are by far the most dominant frameshift mutation in these proteins, although it is possible for a single nucleotide addition to occur. In particular, it has been found that more than 95% of mutations in microsatellites are deletions (Maby et al., Cancer Res, 75(17), September 1 , 2015). The amino acid sequence of each of TGFPR2, ASTE1 and TAFip resulting from a single nucleotide deletion (-1a) frameshift mutation is shown in SEQ ID NO: 2 (TGFPR2), SEQ ID NO: 5 (ASTE1) and SEQ ID NO: 7 (TAF1P).

The detection of MSI in cancer, such as colorectal cancers (CRCs), is performed by profiling the Bethesda panel, which is a reference panel including five microsatellite loci: two mononucleotides (BAT25 and BAT26) and three dinucleotides (D5S346, D2S123 and D17S250) (Cortes-Ciriano et al., Nature Communications, 2017, vol. 8, article no.15180; Vilar & Gruber, Nat Rev Clin Oncol, 2010, vol. 7(3), p.153-162). MSI is classed as high (MSI-H) when there is instability at two or more loci, and is classed as low (MSI-L) when there is instability at one locus (Vilar & Gruber, Nat Rev Clin Oncol, 2010, vol. 7(3), p.153-162). Microsatellites can be classed as stable (MSS) when there is no loci which has instabilities (Vilar & Gruber, Nat Rev Clin Oncol, 2010, vol. 7(3), p.153-162).

About 15% of all CRCs are MSI-H, and MSI has also been reported in glioblastomas, lymphomas, stomach, urinary tract, ovarian and endometrial tumours (Cortes-Ciriano et al., Nature Communications, 2017, vol. 8, article no.15180). It has also been reported that each of TAFip, ASTE1 and TGFPR2 is independently mutated in more than 75% of MSI CRCs (Maby et al., Cancer Res, 75(17), September 1 , 2015).

In addition, about 22% of stomach (gastric) cancers are MSI-H (Cortes-Ciriano et al., Nature Communications, 2017, vol. 8, article no.15180). Furthermore, frameshift mutations in TGF R2 are reported to be found in about 15% of all CRCs, about 44% of all MSI-H cancers, and in particular in about 58% of MSI-H colon cancers and about 80% of MSI-H stomach cancers (Cortes-Ciriano et al., Nature Communications, 2017, vol. 8, article no.15180). Frameshift mutations in ASTE1 are found in about 45% of all MSI-H cancers (Cortes-Ciriano et al., Nature Communications, 2017, vol. 8, article no.15180).

Peptides of TGFPR2 having a frameshift mutation have been reported to be immunogenic, although there are inconsistencies in the results reported, as discussed below.

EP1078000 discloses using fragments of proteins arising from frameshift mutations in the BAX and TGF[3R2 genes to treat cancer, by eliciting T-cell immunity.

Linnebacher et al. (Int J Cancer, 2001, 93, p.6-11) reports that three peptides derived from proteins having frameshift mutations were capable of activating specific CTLs (HLA-A2.1 restricted) in vitro, including a peptide (referred to therein as FSP02: RLSSCVPVA; SEQ ID NO: 33) of TGFPR2 having a -1a frameshift mutation. This peptide was also able to lyse the colorectal cancer cell line HCT116, which carries the corresponding frameshift mutation. However, two other peptides of -1a frameshifted TGFPR2 did not activate CTLs.

Saeterdal et al. (Cancer Immunol Immunother, 2001 Nov, 50(9), 469-476) reports that a peptide (RLSSCVPVA (labelled in Saeterdal et al., Cancer Immunol Immunother as p573); SEQ ID NO: 33 herein) of TGFPR2 having a frameshift mutation was able to generate a CTL line and several CTL clones. One CTL clone was able to kill an HLA-A2+ colon cancer cell line harbouring the frameshifted TGFPR2.

Saeterdal et al. (PNAS, 2001 Nov 6, 98(23), 13255-13260) reports a highly immunogenic peptide (labelled p538; SLVRLSSCVPVALMSAMTTSSSQ (SEQ ID NO: 34 herein)) derived from TGFPR2 having a frameshift mutation, as a target for tumour infiltrating Th cells in MSI+ tumours. This peptide was recognized by two of three patients having spontaneous MSI+ colon cancer, and from all three patients with HNPCC. Several other peptides corresponding to the same frameshift mutation (p540: SPKCIMKEKKSLVRLSSCVPVA (SEQ ID NO: 25 herein), and p541 : PKCIMKEKKKSLVRLSSCV (SEQ ID NO: 26 herein)) were also able to induce T-cell responses in some patients.

However, the studies above have contradictory results, such that it is not clear whether or not the peptides of TGFPR2 having a frameshift mutation are indeed immunogenic. For example, peptide FSP01 (SLVRLSSCV; SEQ ID NO: 27 herein) of Linnebacher et al. is the same as peptide SEQ ID NO: 428 of EP1078000, but Linnebacher et al. reports that this peptide is not immunogenic (Figure 1 of Linnebacher et al.) while EP1078000 reports that this peptide is immunogenic (Figure 14 of EP1078000), albeit only after four rounds of stimulation of the T- cells. Peptide FSP02 (RLSSCVPVA; SEQ ID NO: 28 herein) of Linnebacher et al. is the same as peptide SEQ ID NO: 439 of EP1078000 and peptide p573 of Saeterdal et al., (2001, Cancer Immunol Immunother), but Linnebacher et al. and Saeterdal et al (2001, Cancer Immunol Immunother) report that this peptide is immunogenic (Figure 1 of Linnebacher et al.; abstract, and page 472, column 1 , paragraph 3, of Saeterdal et al.), while EP 1078000 reports that this peptide is not immunogenic even after four rounds of T-cell stimulation (Figure 14 of EP 1078000). Moreover, Saeterdal (2001, PNAS) discloses that the peptides p537 and p621 are not immunogenic but that the peptides p538, p540 and p4541 are immunogenic; however, both p538 and p621 comprise the sequence of peptides p523 and p573 which have been shown to be immunogenic by some studies (as discussed above). Thus, it is unclear why p621 is not immunogenic while p538 is immunogenic. Furthermore, EP1078000 discloses that the peptide SEQ ID NO: 17 thereof is capable of stimulating cultivated T-cell clones derived from a patient with adenocarcinoma (Figures 8 and 9 of EP1078000), but that the peptide SEQ ID NO: 17 thereof does not induce a T-cell response above background values in T-cells from healthy blood donors (Figure 12 of EP1078000). The results shown in Figures 8 and 9 of EP1078000 show that a spontaneous T-cell immune response might have been induced in a patient with cancer and that these T-cells, after cultivation with peptide SEQ ID NO: 17 thereof , can recognise peptide SEQ ID NO: 17. However, these results do not show that the peptide SEQ ID NO: 17 of EP1078000 is a strong enough antigen to induce a protective immune response.

It has also been found that, using engineered antigen-presenting cells, it was possible to stimulate peripheral cytotoxic T-cells obtained from colorectal cancer patients with peptides derived from frameshift mutations found in the patients’ tumours (Maby et al., Cancer Res, 75(17), September 1, 2015). In particular, the peptides were derived from the frameshift mutants of TGFPR2, TAFip and ASTE1. However, T-cells from cancer patients without frameshift mutations, and T-cells from healthy subjects, could not be stimulated to detectable levels, which indicates that the peptides are not sufficiently immunogenic to induce a detectable immune response if used for vaccination.

US 8053552 discloses that peptides derived from -1a frameshifted TGFPR2, TAFip and ASTE1 were able, in vitro, to induce an immune response using T-cells from healthy HLA-A2.1 + donors. However, these results are limited only to HLA-A2.1+ epitopes, and do not show that other HLA class l-restricted T-cells, or any HLA class Il-restricted T-cells, were induced. Historically, vaccines consisting only of HLA class I epitopes have not been successful in treating cancer and, therefore, US 8053552 does not show that the peptides tested therein are an effective vaccine or treatment for cancer.

WO 2020/239937, which is incorporated herein by reference, discloses peptides of TGFPR2 having a frameshift mutation, wherein the peptides are capable of inducing an immune response. The peptides are for use in the treatment of cancer associated with TGFPR2 having a frameshift mutation, particularly cancers associated with a -1a frameshift mutation (“mutTGFpR2”).

WO 2021/239980, which is incorporated herein by reference, discloses peptides of each of ASTE1, TAFip, KIAA2018 and SLC22A9 having a frameshift mutation, and a peptide mixture comprising first and second peptides each independently selected from the aforementioned peptides and peptides of TGFPR2 having a frameshift mutation. The peptides and peptide mixtures are for use in the treatment of cancer, particularly cancer associated with a frameshift mutation in one or more of TGFPR2, ASTE1 , TAFip, KIAA2018 and SLC22A9.

People with Lynch syndrome have a somatic disorder in genes coding for the DNA mismatch repair proteins, which is expected to develop into frameshift mutations, which results in the Lynch syndrome population being at high risk of developing cancer, such as Hereditary NonPolyposis Colorectal Cancer (HNPCC) or hereditary endometrial cancer. CRC is often preceded by the development of polyps, but the removal of these from patients with hereditary CRC (HNPCC) is ineffective in preventing cancer, unlike in patients who do not have HNPCC. In particular, 99% of HNPCCs are MSI-H (Pinheiro el al., British Journal of Cancer, 2015, vol. 113, p. 686-692). Of the MSI-H HNPCC patients, about 90% have a frameshift mutation in the protein TGFPR2 (Pinheiro el al., British Journal of Cancer, 2015, vol. 113, p. 686-692). ASTE1 and TAF1 B are reported to be present in about 90% and 75%, respectively, in MSI-colorectal cancer and in about 85% and 50% in endometrial cancer (Kloor M et al., Clinical Cancer Research, 15 June 2020, 26, p.4503-4510). In addition, it has been shown that these frameshifts are present as early as in pre-malignant crypt foci in the colon (Staffa L et al., PLOS One, 27 March 2015, 10(3)).

Thus, there is a need to provide effective prophylactic, as well as therapeutic, treatments against cancers, particularly cancers associated with MSI and frameshift mutations. In particular, there is a need to provide prophylactic and/or therapeutic treatments for these cancers which are cost effective and can be used to treat or vaccine against as many MSI-H- associated cancers as possible. of Invention

The present invention arises because it has now been found that peptides comprising a fragment of TAFip having a frameshift mutation can be used to induce an immune response against cancer cells and, therefore, are useful for the treatment and/or prophylaxis of cancer associated with TAFip having a frameshift mutation. In particular, it has been found that a peptide comprising the sequence of SEQ ID NO: 21 , which encompasses multiple epitopes, is immunogenic, such that peptides comprising the sequence of SEQ ID NO: 21 are useful for inducing therapeutically- and/or prophylactically-relevant immune responses in a greater number of subjects than previously-known peptides. Thus, peptide mixtures including the peptide comprising the sequence of SEQ ID NO: 21, and more specifically peptide mixtures comprising a first peptide which is a fragment of TGFPR2 having a frameshift mutation, a second peptide which is a fragment of ASTE1 having a frameshift mutation and the peptide comprising the sequence of SEQ ID NO: 21 can be used to induce an immune response in a greater number of subjects than previously-known peptide mixtures. Consequently, the peptide is useful for the treatment and/or prophylaxis of cancer associated with a frameshift mutation in TAFip, and the peptide mixtures are useful for the treatment and/or prophylaxis of cancer associated with frameshift mutations in one or more of TGFPR2, ASTE1 and TAFip. The peptide is particularly useful for the treatment and/or prophylaxis of cancers associated with a - 1a frameshift mutation in TAFip, and the peptide mixtures of the present invention are particularly useful for the treatment and/or prophylaxis of cancers associated with -1a frameshift mutations in one or more of TGFPR2, ASTE1 and TAFip. It has been found that particularly useful peptides comprise a fragment which corresponds to at least part of the mutated amino acid sequence resulting from the frameshift mutation in the relevant protein. In particular, the peptides and peptide mixtures are useful as prophylactic cancer vaccines, and, more particularly, for the prophylaxis of Lynch syndrome patients. The majority of hereditary cancers evolving from the Lynch syndrome patient population are of MSI phenotype and characteristically express frameshift mutated TGFPR2, ASTE1 and TAF1B as early events of cancer development. In addition, the peptides and peptide mixtures are useful for the treatment of cancers associated with a frameshift mutation in TGFPR2, ASTE1 or TAFip, such as colon, endometrial, gastric and ovarian cancers. The peptides of the invention, and in the peptide mixtures of the invention, comprise multiple nested epitopes, such that the peptides comprise epitopes for more than one HLA allele. This provides the advantage that the peptides are capable of inducing an immune response in patients having different HLA alleles, such that the peptides are useful as a universal treatment and/or vaccine. In addition, each peptide of the invention contains few or no amino acid residues from the wild-type amino acid sequence of the protein from which each peptide is derived, thereby reducing the risk that the peptides of the invention induce an autoimmune response.

Thus, in a first aspect of the invention, there is provided a peptide mixture comprising a first, second and third peptide, wherein the first peptide is capable of inducing an immune response against a TGFPR2 -1a frameshift mutant protein, wherein the first peptide comprises i) an immunogenic fragment of SEQ ID NO: 3, wherein the immunogenic fragment comprises at least 8 consecutive amino acids of SEQ ID NO: 3 including at least one of positions 121 and 135 of SEQ ID NO: 3, or ii) an immunogenic fragment of SEQ ID NO: 2, wherein the immunogenic fragment comprises at least s consecutive amino acids of SEQ ID NO: 8; the second peptide is capable of inducing an immune response against a ASTE1 -1a frameshift mutant protein, wherein the second peptide comprises an immunogenic fragment of SEQ ID NO: 5, wherein the immunogenic fragment comprises at least 8 consecutive amino acids of SEQ ID NO: 19; and the third peptide is capable of inducing an immune response against a TAFip -1a frameshift mutant protein, wherein the third peptide comprises the amino acid sequence of SEQ ID NO: 21.

Preferably, the first peptide comprises at least 9, preferably at least 10, consecutive amino acids of SEQ ID NO: 3, or the first peptide comprises at least 9, preferably at least 10, consecutive amino acids of SEQ ID NO: 2.

Advantageously, the first peptide comprises position 121 to 132 of SEQ ID NO: 3, positions 129 to 137 of SEQ ID NO: 3, positions 135 to 146 of SEQ ID NO: 3 or positions 2 to 17 of SEQ ID NO: 2, positions 10 to 18 of SEQ ID NO: 2 or positions 16 to 33 of SEQ ID NO: 2, preferably wherein the amino acid corresponding to position 121 or 135 of SEQ ID NO: 3 is glycine.

Conveniently, the first peptide comprises the amino acid sequence of one of SEQ ID NOs: 8-18, preferably wherein the peptide consists of one of SEQ ID NOs: 8-18.

Preferably, the first peptide comprises the amino acid sequence of SEQ ID NO: 10, preferably wherein the first peptide consists of SEQ ID NO: 10.

Conveniently, the immunogenic fragment of SEQ ID NO: 5 comprises at least 15 consecutive amino acids of SEQ ID NO: 19. Advantageously, the second peptide comprises the amino acid sequence of SEQ ID NO: 19, preferably wherein the second peptide consists of SEQ ID NO: 19.

Preferably, the third peptide consists of SEQ ID NO: 21.

In a second aspect of the invention, there is provided a peptide capable of inducing an immune response against a TAFip -1a frameshift mutant protein, wherein the peptide comprises the amino acid sequence of SEQ ID NO: 21.

Advantageously, the peptide comprises no more than 29 amino acids.

Preferably, the peptide consists of the amino acid sequence of SEQ ID NO: 21.

In a third aspect of the invention, there is provided a T-cell mixture comprising a first T-cell specific for the first peptide according to the first aspect, a second T-cell specific for the second peptide according to the first aspect and a third T-cell specific for the third peptide according to the first aspect.

In a fourth aspect of the invention, there is provided a T-cell specific for a peptide capable of inducing an immune response against a TAFip -1a frameshift mutant protein, wherein the peptide comprises the amino acid sequence of SEQ ID NO: 21.

In a fifth aspect of the invention, there is provided a T-cell receptor, or an antigen-binding fragment thereof, specific for a peptide capable of inducing an immune response against a TAFip -1a frameshift mutant protein, wherein the peptide comprises the amino acid sequence of SEQ ID NO: 21.

Advantageously, in both the fourth and the fifth aspect, the peptide comprises no more than 29 amino acids.

In a sixth aspect of the invention, there is provided at least one nucleic acid molecule, wherein the nucleic acid molecule or molecules individually or collectively comprise nucleotide sequences encoding the first, second and third peptides according to the first aspect, or the at least one nucleic acid molecule comprises a nucleotide sequence encoding the peptide according to the second aspect. In a seventh aspect of the invention, there is provided a vector comprising the at least one nucleic acid molecule according to the sixth aspect.

In an eighth aspect of the invention, there is provided a host cell comprising the vector according to the seventh aspect.

In a ninth aspect of the invention, there is provided a pharmaceutical composition comprising a peptide mixture according to the first aspect, a peptide according to the second aspect, a T-cell mixture according to the third aspect, a T-cell according to the fourth aspect, at least one nucleic acid molecule according to the sixth aspect, a vector according to the seventh aspect or a host cell according to the eighth aspect, and a pharmaceutically-acceptable carrier, diluent or excipient.

In a tenth aspect of the invention, there is provided a peptide mixture according to the first aspect, a peptide according to the second aspect, a T-cell mixture according to the third aspect, a T-cell according to the fourth aspect, a T-cell receptor or an antigen-binding fragment thereof according to the fifth aspect, at least one nucleic acid molecule according to the sixth aspect, a vector according to the seventh aspect, a host cell according to the eighth aspect or a pharmaceutical composition according to the ninth aspect, for use in medicine.

Preferably, the peptide mixture, peptide, T-cell mixture, T-cell, T-cell receptor or antigen-binding fragment thereof, at least one nucleic acid molecule, vector, host cell or pharmaceutical composition for use in medicine is for use in the treatment and/or prophylaxis of cancer, preferably in a Lynch syndrome patient.

Advantageously, the peptide mixture, peptide, T-cell mixture, T-cell, T-cell receptor or antigenbinding fragment thereof, at least one nucleic acid molecule, vector, host cell or pharmaceutical composition is for use in the treatment and/or prophylaxis of colorectal cancer, gastric cancer or endometrial cancer.

Conveniently, the peptide mixture, peptide, T-cell mixture, T-cell, T-cell receptor or antigenbinding fragment thereof, at least one nucleic acid molecule, vector, host cell or pharmaceutical composition is for use in the prophylaxis of cancer. In an eleventh aspect of the invention, there is provided a method of selecting a peptide mixture, a peptide, at least one nucleic acid molecule, vector, host cell, T-cell mixture or a pharmaceutical composition for administration to a patient, comprising: i) identifying a Lynch syndrome patient, and ii) selecting a peptide mixture according to the first aspect, a peptide according to the second aspect, a T-cell mixture according to the third aspect, a T-cell according to the fourth aspect, a T-cell receptor or antigen-binding fragment thereof according to the fifth aspect, at least one nucleic acid molecule according to the sixth aspect, a vector according to the seventh aspect, a host cell according to the eighth aspect or a pharmaceutical composition according to the ninth aspect.

In a twelfth aspect of the invention, there is provided a method of treating, or prophylaxis of, cancer comprising administering, to a patient in need thereof, a peptide mixture according to the first aspect, a peptide according to the second aspect, a T-cell mixture according to the third aspect, a T-cell according to the fourth aspect, a T-cell receptor or an antigen-binding fragment thereof according to the fifth aspect, at least one nucleic acid molecule according to the sixth aspect, a vector according to the seventh aspect, a host cell according to the eighth aspect or a pharmaceutical composition according to the ninth aspect.

Conveniently, the patient is a Lynch syndrome patient, and the method of prophylaxis comprises the step of identifying a Lynch syndrome patient before administering the peptide mixture, peptide, T-cell mixture, T-cell, T-cell receptor or antigen-binding fragment thereof, nucleic acid molecule, vector, host cell or pharmaceutical composition to the patient.

In a thirteenth aspect of the invention, there is provided a method of eliciting an immune response comprising administering, to a patient in need thereof, a peptide mixture according to the first aspect, a peptide according to the second aspect, a T-cell mixture according to the third aspect, a T-cell according to the fourth aspect, a T-cell receptor or an antigen-binding fragment thereof according to the fifth aspect, a nucleic acid molecule according to the sixth aspect, a vector according to the seventh aspect, a host cell according to the eighth aspect or a pharmaceutical composition according to the ninth aspect.

The term “peptide”, as used herein, refers to a polymer of amino acid residues. The term also applies to amino acid polymers in which one or more amino acid residues is a modified residue, or a non-naturally occurring residue, such as an artificial chemical mimetic of a corresponding naturally occurring amino acid, as well as to naturally occurring amino acid polymers. The peptide may be linked to another agent or moiety. The term “fragment”, as used herein, refers to a series of consecutive amino acids from a longer polypeptide or protein.

The percentage “identity” between two sequences may be determined using the BLASTP algorithm version 2.2.2 Altschul, Stephen F., Thomas L. Madden, Alejandro A. Schaffer, Jinghui Zhang, Zheng Zhang, Webb Miller, and David J. Lipman (1997), "Gapped BLAST and PSI- BLAST: a new generation of protein database search programs", Nucleic Acids Res. 25:3389- 3402), using default parameters. In particular, the BLAST algorithm can be accessed in the internet using the URL https://blast.ncbi.nlm.nih.gov/Blast.cgi.

The term “immune response”, as used herein, refers in some embodiments to a T-cell mediated immune response (i.e. T-cell activation) upon recognition of a peptide. The T-cell response may be a HLA-I mediated T-cell response and/or a HLA-II mediated T-cell response. The immune response may be a response by any alpha beta (op) T-cells and/or gamma delta (yb) T-cells, such that the peptides may or may not be presented to the T-cells by major histocompatibility (MHC) molecules on the surface of antigen-presenting cells.

The term “frameshift mutant”, as used herein, refers to a polypeptide encoded by a nucleic acid sequence having an addition or deletion of one or two nucleotides compared to the wild-type sequence of the nucleic acid, thereby resulting in different codons as of the point of mutation.

The term “-1a frameshift mutant”, as used herein, refers to a polypeptide resulting from the deletion of a single nucleotide from the wild-type nucleic acid sequence.

The term “-1a frameshift mutation” refers to a change in the amino acid sequence of a polypeptide compared to the wild-type amino acid sequence of the polypeptide, resulting from the deletion of a single nucleotide from the nucleic acid sequence encoding that polypeptide.

The term “mutTGFpR2”, as used herein, refers to a TGFPR2 protein which has a -1a frameshift mutation. The amino acid sequence of mutTGFpR2 is shown in SEQ ID NO: 2.

The term “mutASTEI”, as used herein, refers to a ASTE1 protein which has a -1a frameshift mutation. The amino acid sequence of mutASTEI is shown in SEQ ID NO: 5. The term “mutTAFI B”, as used herein, refers to a TAF1 B protein which has a -1a frameshift mutation. The amino acid sequence of mutTAFI B is shown in SEQ ID NO: 7.

The term “amino acid substitution”, as used herein, refers to the replacement of an amino acid in a polypeptide with a different amino acid, compared to the wild-type amino acid sequence of the polypeptide.

The term “peptide mixture”, as used herein, refers to three or more peptides which are mixed but not chemically combined. The mixtures may be present as a dry powder, solution, suspension or colloid, and may be homogeneous or heterogeneous.

The term “nucleic acid” or “nucleic acid molecule”, as used herein, refers to a polymer of multiple nucleotides. The nucleic acid may comprise naturally occurring nucleotides or may comprise artificial nucleotides such as peptide nucleotides, morpholin and locked nucleotides as well as glycol nucleotides and threose nucleotides.

The term “nucleotide”, as used herein, refers to naturally occurring nucleotides and synthetic nucleotide analogues that are recognised by cellular enzymes.

The term “pharmaceutical composition”, as used herein, means a pharmaceutical preparation suitable for administration to an intended human or animal subject for therapeutic purposes.

Brief Description of the Figures

Figure 1 is a graph showing T-cell proliferation after one round of stimulation with a peptide mixture containing fsp2 (SEQ ID NO: 10) and fsp4 (SEQ ID NO: 12).

Figure 2 is a graph showing T-cell proliferation after a second round of stimulation with a peptide mixture containing fsp2 (SEQ ID NO: 10) and fsp4 (SEQ ID NO: 12)

Figure 3 is a graph showing the T-cell proliferation in samples from Donors 2, 3, and 4.

Figure 4 is a graph showing T-cell proliferation induced by fsp2 (SEQ ID NO: 10), fsp6 (SEQ ID NO: 13) and fsp7 (SEQ ID NO: 22), after stimulation with a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23).

Figure 5 is a graph showing T-cell proliferation after two rounds of in vitro stimulation of PMBCs from healthy donors with a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23). Figure 6 is a graph showing T-cell proliferation after two and three rounds of in vitro stimulation of PMBCs from a healthy donor with a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23)

Figure 7 is a graph showing T-cell proliferation induced by fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) or fsp9 (SEQ ID NO: 23), individually, or a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23), after in vitro stimulation of PMBCs from a healthy donor with a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23).

Figure 8 is a graph showing T-cell proliferation induced by fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) or fsp9 (SEQ ID NO: 23), individually, or a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23), after in vitro stimulation of PMBCs from a healthy donor with a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23).

Figure 9 is a graph showing T-cell proliferation induced by fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) or fsp9 (SEQ ID NO: 23), individually, or a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23), after in vitro stimulation of PMBCs from a healthy donor with a peptide mixture containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23).

Figure 10 is a graph showing the T-cell proliferation induced by fsp15 (SEQ ID NO: 127) after in vitro stimulation of PMBCs from a healthy donor with a peptide mixture containing fsp17 (SEQ ID NO: 17), fsp15 (SEQ ID NO: 20) and fsp16 (SEQ ID NO: 24).

Figure 11 is a graph showing the T-cell proliferation induced by fsp17 (SEQ ID NO: 17), fsp15 (SEQ ID NO: 20) or fsp16 (SEQ ID NO: 24), individually, or by a mixture containing fsp17 (SEQ ID NO: 17), fsp15 (SEQ ID NO: 20) and fsp16 (SEQ ID NO: 24), after two rounds of in vitro stimulation of PMBCs from a healthy donor with a peptide mixture containing fsp17 (SEQ ID NO: 17), fsp15 (SEQ ID NO: 20) and fsp16 (SEQ ID NO: 24).

Figure 12 shows the development of the TGFPR2 consensus sequence and peptides.

Figure 13 shows the development of the ASTE1 peptides.

Figure 14 shows the development of the TAFip peptides.

Figure 15 shows the method of synthesis of fsp18.

Figure 16 is a LIPLC trace of crude fsp18, after stage 2 of Figure 15.

Figure 17 is a LIPLC trace of purified fsp18, after stage 3 of Figure 15.

Figure 18 is a LIPLC trace of fsp18 acetate salt, after stage 4 of Figure 15.

Detailed Description The invention relates, in general terms, to a peptide mixture comprising a peptide derived from TGFPR2, a peptide derived from ASTE1 and a peptide derived from TAFip, each having a frameshift mutation. Each peptide comprises a fragment of the relevant frameshift mutant protein and is able to induce an immune response against the relevant frameshift mutant protein. In some embodiments, each frameshift mutant protein is a -1a frameshift mutant (referred to herein as “mutTGFpR2”, “mutASTEI”, and “mutTAFip”, respectively). The amino acid sequence of each of the TGFPR2, ASTE1 and TAFip -1a frameshift mutant proteins is shown in SEQ ID NOs: 2, 5 and 7, respectively.

Each of the peptides comprises a sequence which corresponds to an immunogenic fragment of the -1a frameshifted mutant protein from which the peptide is derived (i.e. one of mutTGFpR2 (SEQ ID NO: 2), ASTE1 (SEQ ID NO: 5) and TAFip (SEQ ID NO: 7) displayed by HLA-I or H LA-11 molecules on the surface of cells, and/or to which individuals generally have a reactive T-cell in their T-cell repertoire. Each peptide, whether present as a single peptide preparation or in a peptide mixture, is able to induce an immune response against the -1a frameshifted mutant protein from which the peptide in question is derived. Preferably, the immune response is a T- cell response, comprising both HLA-l-restricted T-cells, such as CD8+ T-cells, and HLA-II- restricted T-cells, such as CD4+ T-cells. In particular, the peptides of the invention, and the peptides in the peptide mixtures of the invention, may encompass multiple nested epitopes, such that each peptide may comprise epitopes for more than one HLA allele. This provides the advantage that the peptides are capable of inducing an immune response in patients having different HLA alleles, such that the peptides are useful as a universal treatment and/or vaccine. In addition, the peptides of the invention contain few or no amino acids from the wild-type amino acid sequence of the protein from which they are derived. In other words, the peptides of the invention are mostly or entirely derived from the amino acid sequence of the corresponding protein which has been altered as a result of the frameshift mutation. This provides the advantage that the risk of the peptides inducing an autoimmune response is minimised. Furthermore, the peptides in the peptide mixtures of the invention can have a glycine residue at the C-terminus thereof, which serves as a linker for conjugation of the peptide to other molecules, such as other peptides, carriers, adjuvants, etc.

Features which apply generally to the peptides derived from TGFPR2 and the peptides derived from ASTE1 , and to the peptide mixtures of the invention, are set out immediately below, while features applying more specifically to a peptide of a particular frameshift mutant protein are described later. Features generally applicable to the first and second peptides

Features which apply generally to the peptides derived from TGFPR2 and the peptides derived from ASTE1 , are set out immediately below. Features which apply generally to the peptides derived from TGFPR2, the peptides derived from ASTE1 and the peptides derived from TAFip, and features applying more specifically to a peptide of a particular frameshift mutant protein, are described later.

In some embodiments, the immunogenic fragment of each of the first and second peptide independently comprises at least 8, at least 9, at least 10, at least 12, at least 14, at least 16, at least 18, at least 20, at least 22, at least 24, at least 26, at least 28, at least 30 or at least 32 amino acids.

In some embodiments, the immunogenic fragment of each of the first and second peptide independently comprises no more than 100, 50 or 40 amino acids. For example, the immunogenic fragment may comprise no more than 35, 33, 31 , 29, 27, 25, 23, 21 , 19, 17, 15, 13, 11 or 9 amino acids.

In some embodiments, each of the first and second peptide independently comprises at least 9, at least 10, at least 12, at least 14, at least 16, at least 18, at least 20, at least 22, at least 24, at least 26, at least 28, at least 30 or at least 32 amino acids.

In some embodiments, each of the first and second peptide independently comprises no more than 100, 50 or 40 amino acids. For example, each of the first and second peptides, independently, may comprise no more than 35, 33, 31 , 29, 27, 25, 23, 21 , 19, 17, 15, 13, 11 or 9 amino acids.

Thus, in some embodiments, the first and/or the second peptide comprises other amino acids outside of the immunogenic fragment of the relevant frameshifted protein. However, in other embodiments, the first and/or the second peptide is the same length as the immunogenic fragment, such that the peptide is an immunogenic fragment of the relevant frameshift mutant protein.

Sequence identity to the frameshifted protein outside of the immunogenic fragment

The first and/or second peptide may each independently have at least 70% sequence identity to the relevant frameshift mutant protein outside of the immunogenic fragment. In some embodiments, the first and/or second peptide each independently has at least 75%, at least 80%, at least 85%, at least 90%, at least 92%, at least 93%, at least 94% or at least 95% sequence identity to the relevant frameshift mutant protein outside of the immunogenic fragment. In some embodiments, the first and/or second peptide each independently has 100% sequence identity to the relevant frameshift mutant protein outside of the immunogenic fragment.

Position of the fragment within the peptide

In some embodiments, the immunogenic fragment starts at position one, two, three, four, five, six, seven, eight, nine, ten or eleven from the N-terminus of the peptide. In some embodiments, the immunogenic fragment ends at position one, two three, four, five, six, seven, eight, nine, ten or eleven from the C-terminus of the peptide. In other embodiments, the immunogenic fragment is the C-terminus or the N-terminus of the peptide.

Features generally applicable to the first, second and third peptides

Features which apply generally to the peptides derived from TGFPR2, the peptides derived from ASTE1 and the peptides derived from TAFip are described immediately below, while features applying more specifically to a peptide of a particular frameshift mutant protein, are described later.

In some embodiments, the first, second and/or third peptide each independently comprises no more than 8 amino acids from the wild-type amino acid sequence of the corresponding protein. In some embodiments, the first, second and/or third peptide each independently comprises no more than 7, no more than 6, no more than 5, no more than 4, no more than 3, no more than 2 or no more than 1 amino acid from the wild-type amino acid sequence of the corresponding protein.

When a peptide comprises one or more amino acids from the wild-type amino acid sequence of the corresponding protein, these amino acids are preferably at the N-terminus of the protein.

In some embodiments, the first, second and/or third peptide each independently comprises no amino acids from the wild-type amino acid sequence of the corresponding protein. Thus, in these embodiments, the first, second and/or third peptide each independently consists only of amino acids from the amino acid sequence resulting from the frameshift mutation in the corresponding protein. In some embodiments, the immunogenic fragment of each of the first, second and/or third peptide, independently, or the first, second and/or third peptide each independently, has a glycine residue at the C-terminus thereof (i.e. the C-terminus is a glycine residue). The glycine residue may be a glycine residue which occurs naturally in the amino acid sequence of the corresponding protein, or it may be a glycine residue which has been artificially added to the C- terminus of the peptide.

In some embodiments, any or each of the first, second and third peptides is conjugated to a further substance.

In some embodiments, any or each of the first, second and third peptides is a lyophilisate or is dissolved in solution. In some embodiments, any or each of the first, second and third peptides is an acetate salt.

TAFip peptide

The peptide derived from mutTAFip is also referred to herein as “the third peptide”, and the features described below are applicable to the peptide in any context, for example when provided as the peptide per se or in a peptide mixture. The third peptide comprises the sequence of SEQ ID NO: 21.

In some embodiments, the third peptide comprises at least 26, at least 28, at least 30 or at least 32 amino acids.

In some embodiments, the third peptide comprises no more than 100, 50 or 40 amino acids. For example, the third peptide may comprise no more than 35, 34, 33, 32, 31, 30, 29, 28 27 or 26 amino acids.

In some embodiments, the third peptide consists of the sequence of SEQ ID NO: 21. In particular, it is expected that this peptide is immunogenic and encompasses a broad range of epitopes, thereby providing a universal vaccine which targets a broad range of HLA alleles.

In some embodiments, the third peptide is a lyophilisate or is dissolved in solution. In some embodiments, the third peptide is an acetate salt. In some embodiments, the third peptide consists of an acetate salt of SEQ ID NO: 21.

Peptide Mixture The invention also provides mixtures comprising the above-described peptide, a peptide capable of inducing an immune response against a TGFPR2 -1a frameshift mutant protein (mutTGFpR2; SEQ ID NO: 2) as described below and a peptide capable of inducing an immune response against a ASTE1 -1a frameshift mutant protein (mutASTEI; SEQ ID NO: 5) as described below.

First peptide (TGF/3R2)

The peptide derived from mutTGFpR2 (SEQ ID NO: 2) is also referred to herein as “the first peptide”.

In some embodiments, in the peptide capable of inducing an immune response against a TGFPR2 -1a frameshift mutant protein (mutTGFpR2; SEQ ID NO: 2), the immunogenic fragment comprises at least 8 consecutive amino acids of SEQ ID NO: 3, including at least one of positions 121 and 135, or at least 8 consecutive amino acids of SEQ ID NO: 8. In some embodiments, the immunogenic fragment comprises at least 9 consecutive amino acids. In some embodiments, the immunogenic fragment comprises at least 10 consecutive amino acids. In some embodiments, the immunogenic fragment comprises at least 12 consecutive amino acids. In some embodiments, the immunogenic fragment comprises at least 15 consecutive amino acids. In some embodiments, the immunogenic fragment comprises at least 17 consecutive amino acids. In some embodiments, the immunogenic fragment comprises at least 20 consecutive amino acids. In other embodiments, the immunogenic fragment comprises at least 24 consecutive amino acids. In further embodiments, the fragment comprises at least 33 consecutive amino acids.

In some embodiments, the immunogenic fragment comprises no more than 50 amino acids. In some embodiments, the immunogenic fragment comprises no more than 33 amino acids. In other embodiments, the immunogenic fragment comprises no more than 27, 24, 20, 17 or 9 amino acids.

In some embodiments, the peptide capable of inducing an immune response against mutTGFpR2 (SEQ ID NO: 2) comprises at least 9 amino acids. In some embodiments, the peptide comprises at least 17 amino acids. In some embodiments, the peptide comprises at least 20 amino acids. In other embodiments, the peptide comprises at least 24 amino acids. In some embodiments, the peptide comprises a least 27 amino acids. In further embodiments, the peptide comprises at least 33 amino acids. In some embodiments, the peptide comprises no more than 33 amino acids. In some embodiments, the peptide comprises no more than 27 amino acids. In other embodiments, the peptide comprises no more than 24 amino acids. In some embodiments, the peptide comprises no more than 20 amino acids. In some embodiments, the peptide comprises no more than 17 amino acids. In further embodiments, the peptide comprises no more than 9 amino acids.

In some embodiments, the immunogenic fragment or the peptide comprises a glycine residue at the C-terminus thereof. The glycine residue may be a glycine residue which occurs naturally in the amino acid sequence of mutTGFpR2, or it may be a glycine residue which has been artificially added to the C-terminus of the peptide.

Bridging region

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) or peptide comprises at least one amino acid from the wild-type sequence of TGFPR2 (SEQ ID NO: 1) (i.e. position 1 to position 127 of SEQ ID NO: 2) consecutive with at least one amino acid from the amino acid sequence resulting from the frameshift mutation (i.e. position 128 to position 161 of SEQ ID NO: 2). Thus, the immunogenic fragment or peptide may be a fragment of mutTGFpR2 (SEQ ID NO: 2) which overlaps the amino acid sequence unaffected by the frameshift mutation and the amino acid sequence resulting from the frameshift mutation. In some embodiments, the immunogenic fragment or peptide comprises 2, 3, 4, 5, 6, 7 or 8 consecutive amino acids from the wild-type amino acid sequence of TGFPR2 (SEQ ID NO: 1). In some embodiments, the at least one amino acid from the wild-type sequence of TGFPR2 (SEQ ID NO: 1) is consecutive with 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 amino acids from the amino acid sequence resulting from the frameshift mutation. In some embodiments, the immunogenic fragment or peptide has only 8 amino acids from the wild-type amino acid sequence of TGFPR2 (SEQ ID NO: 1). In some embodiments, the immunogenic fragment or peptide contains no amino acids from the wild-type amino acid sequence of TGFPR2 (SEQ ID NO: 1).

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) comprises position 127 and position 128 of SEQ ID NO: 2, wherein the amino acid at position 127 of SEQ ID NO: 2 corresponds to the amino acid at position 127 of wild-type TGFPR2 (SEQ ID NO: 1). This corresponds to positions 8 and 9 of SEQ ID NO: 8, and positions 127 and 128 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment comprises position 126 to position 128, position 125 to position 128, position 124 to position 128, position 123 to position 128, position 122 to position 128, position 121 to position 128 or position 120 to position 128 of SEQ ID NO: 2 or SEQ ID NO: 3 (which correspond to position 7 to position 9, position 6 to position 9, position 5 to position 9, position 4 to position 9, position 3 to position 9, position 2 to position 9, or position 1 to position 9 of SEQ ID NO: 8, respectively).

In particular, it is expected that at least the two amino acid residues bridging the wild-type amino acid sequence of TGFPR2 (SEQ ID NO: 1) and the amino acid sequence resulting from the frameshift mutation are helpful for providing an effective epitope, and for the peptide to have particularly good immunogenicity. In particular, Figures 1 and 2 show that peptides comprising amino acids from the wild-type sequence of TGFPR2 (SEQ ID NO: 1) (i.e. fsp1 (SEQ ID NO: 9), fsp2 (SEQ ID NO: 10) and fsp5 (SEQ ID NO: 8)) are more immunogenic than peptides which do not comprise amino acids from the wild-type sequence of TGFPR2 (SEQ ID NO: 1) (i.e. fsp3 (SEQ ID NO: 11) and fsp4 (SEQ ID NO: 12)). It is also expected that the presence of more than one amino acid from the wild-type sequence of TGFPR2 (SEQ ID NO: 1), consecutive with at least one amino acid from the amino acid sequence resulting from the frameshift mutation, is likely to improve the immunogenicity of the peptide. In particular, it is expected that five, six, seven or eight amino acids from the wild-type sequence of TGFPR2 (SEQ ID NO: 1), consecutive with at least one amino acid from the amino acid sequence resulting from the frameshift mutation, will be particularly helpful to the immunogenicity of the peptide. However, it is preferred that the peptide contains no more than eight amino acids from the wild-type sequence of TGFPR2, in order to balance improved immunogenicity with the requirement to reduce the risk of the peptide inducing an autoimmune response.

Fsp 1, fsp3, fsp5 and fsp6

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) comprises positions 6 to 13 of SEQ ID NO: 8, positions 10 to 18 of SEQ ID NO: 8, or positions 18 to 33 of SEQ ID NO: 8. In this instance, the peptide comprises no more than 40 amino acids. In some embodiments, the peptide comprises no more than 27 amino acids. In some embodiments, the immunogenic fragment comprises positions 6 to 17, positions 7 to position 22 or positions 16 to position 33 of SEQ ID NO: 8. In some embodiments, the immunogenic fragment comprises positions 2 to 22 of SEQ ID NO: 8. In some embodiments, the immunogenic fragment comprises positions 6 to 17 of SEQ ID NO: 8, and the immunogenic fragment starts at position six from the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises positions 2 to position 22 of SEQ ID NO: 8, and the immunogenic fragment starts at position two from the N-terminus of the peptide. In other embodiments, the immunogenic fragment comprises position 1 to position 17, position 1 to position 24, or position 1 to position 27, of SEQ ID NO: 8, and the immunogenic fragment is the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises position 16 to position 33 of SEQ ID NO: 8, and the immunogenic fragment starts at position three from the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises position 14 to position 33 of SEQ ID NO: 8. In some embodiments, the immunogenic fragment comprises position 14 to position 33 of SEQ ID NO: 8, and the fragment is the N-terminus of the peptide.

In some embodiments, the peptide comprises a glycine residue that the C-terminus thereof. The glycine residue may be a glycine residue which occurs naturally in the amino acid sequence of mutTGFpR2, or it may be a glycine residue which has been artificially added to the C-terminus of the peptide.

In some embodiments, the immunogenic fragment comprises the amino acid sequence of SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 11 , SEQ ID NO: 13 or SEQ ID NO 18. In some embodiments, the immunogenic fragment consists of the amino acid sequence of SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 11 , SEQ ID NO: 13 or SEQ ID NO: 18. In some embodiments, the peptide capable of inducing an immune response against mutTGFpR2 consists of the amino acid sequence of SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 11 , SEQ ID NO: 13 or SEQ ID NO: 18. When the peptide consists of the amino acid sequence of SEQ ID NO: 9, the peptide is referred to herein as “fsp1”. When the peptide consists of the amino acid sequence of SEQ ID NO: 11 , the peptide is referred to herein as “fsp3”. When the peptide consists of the amino acid sequence of SEQ ID NO: 8, the peptide is referred to herein as “fsp5”. When the peptide consists of the amino acid sequence of SEQ ID NO: 13, the peptide is referred to herein as fsp6. When the peptide consists of the amino acid sequence of SEQ ID NO: 18, the peptide is referred to herein as “fsp17a”.

Fsp2, fsp4 and fsp6a

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) has an amino acid substitution compared to the naturally-occurring amino acid sequence of mutTGFpR2 (SEQ ID NO: 2). Thus, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) may comprise at least 8 consecutive amino acids of SEQ ID NO: 3, and includes at least one of positions 121 and 135 of SEQ ID NO: 3. In some embodiments, the peptide comprises only one of positions 121 and 135 of SEQ ID NO: 3. In particular, positions 121 and 135 of SEQ ID NO: 3 correspond to positions 121 and 135 of mutTGFpR2 (SEQ ID NO: 2), respectively, which are both cysteine residues. The amino acid substitutions at positions 121 and 135 of SEQ ID NO: 3 are from cysteine to any other amino acid. Thus, the amino acid at positions 121 and 135 of SEQ ID NO: 3 is, independently, one of alanine, arginine, asparagine, aspartic acid, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine. Preferably, the amino acid substitution is to glycine.

The amino acid substitution at position 121 and/or 135 of SEQ ID NO: 3, from cysteine to any other amino acid, is useful in preventing issues with production, stability, quality and immunology of the peptide. In particular, the peptides capable of inducing an immune response against TGFPR2 are derived from an optimised consensus sequence (SEQ ID NO: 8) as discussed in WO 2020/239937 (page 17, line 25, to page 18, line 5; Examples 1-6; and Figure 1 of WO 2020/239937, which are incorporated herein by reference), and it has been found that the optimised consensus sequence can be difficult to synthesise due to its length. In addition, the solubility, stability and immunogenicity of the optimised consensus sequence (SEQ ID NO: 8) can be subject to improvement. In particular, the presence of one or more cysteine residues in a peptide can lead to molecular rearrangement and/or polymerisation of the peptide, due to the formation of inter- and/or intra-molecular disulphide bonds. This rearrangement and/or polymerisation may reduce the immunological potency of the peptide, and may induce unwanted inflammatory side effects through, for example, antibody formation and allergic reactions. The substitution of one or more cysteine residues in the peptide reduces the risk of these potential problems. Thus, in some embodiments, the substitution of one or more cysteine residues of the optimised consensus sequence improves the ease of production, the stability, the quality and the immunology of the peptide, but such substitutions are not essential for the present invention.

Range of positions forfsp2, fsp4 and fsp6a

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 115 to position 122, position 116 to position 123, position 117 to position 124, position 118 to position 125, position 119 to position 126, position 120 to position 127, position 121 to position 128, position 128 to position 135, position 129 to position 136, position 130 to position 137, position 131 to position 138, position 132 to position 139, position 133 to position 140, position 134 to position 141 or position 135 to position 142 of SEQ ID NO: 3.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 129 to position 137 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 115 to position 126, position 116 to position 127, position 117 to position 128, position 118 to position 129, position 119 to position 130, position

120 to position 131, position 121 to position 132, position 124 to position 135, position 125 to position 136, position 126 to position 137, position 127 to position 138, position 128 to position 139, position 129 to position 140, position 130 to position 141 , position 131 to position 142, position 132 to position 143, position 133 to position 144, position 134 to position 145 or position 135 to position 146 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of SEQ ID NO: 3 having an amino acid substitution comprises position 115 to position 129, position 116 to position 130, position 117 to position 131 , position 118 to position 132, position 119 to position 133, position 120 to position 134, position 121 to position 135, position 122 to position 136, position 123 to position 137, position 124 to position 138, position 125 to position 139, position 126 to position 140, position 127 to position 141, position 128 to position 142, position 129 to position 143, position 130 to position 144, position 131 to position 145, position 132 to position 146, position 133 to position 147, position 134 to position 148 or position 135 to position 149 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of SEQ ID NO: 3 comprises position 119 to position 130, position 119 to position 133, position 120 to position 131, position 120 to position 134, position 121 to position 132, position

121 to position 135, position 133 to position 144, position 133 to position 147, position 134 to position 145, position 134 to position 148, position 135 to position 146, or position 135 to position 149 of SEQ ID NO: 3.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution consists of position 115 to position 122, position 116 to position 123, position 117 to position 124, position 118 to position 125, position 119 to position 126, position 120 to position 127, position 121 to position 128, position 128 to position 135, position 129 to position 136, position 130 to position 137, position 131 to position 138, position 132 to position 139, position 133 to position 140, position 134 to position 141 or position 135 to position 142 of SEQ ID NO: 3.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution consists of position 129 to position 137 of SEQ ID NO: 3.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution consists of position 115 to position 126, position 115 to position 129, position 116 to position 127, position 116 to position 130, position 117 to position 128, position 117 to position 131, position 118 to position 129, position 118 to position 132, position 119 to position 130, position 119 to position 133, position 120 to position 131, position 120 to position 134, position 121 to position 132, position 121 to position 135, position 122 to position 136, position 123 to position 137, position 124 to position 135, position 124 to position 138, position 125 to position 136, position 125 to position 139, position 126 to position 137, position 126 to position 140, position 127 to position 138, position 127 to position 141, position 128 to position 139, position 128 to position 142, position 129 to position 140, position 129 to position 143, position 130 to position 141, position 130 to position 144, position 131 to position 142, position 131 to position 145, position 132 to position 143, position 132 to position 146, position 133 to position 144, position 133 to position 147, position 134 to position 145, position 134 to position 148, position 135 to position 146 or position 135 to position 149 of SEQ ID NO: 3.

Fsp2, fsp6a (and fsp5 with a G-to-C substitution) and fsp17

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 121, but not position 135, of SEQ ID NO: 3. In some embodiments, the peptide comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or has 100%, sequence identity to SEQ ID NO: 2 outside of the immunogenic fragment. In some such embodiments, the peptide comprises 100% sequence identity to SEQ ID NO: 2 outside of the fragment. In some embodiments, the peptide comprises no more than 33 amino acids, no more than 27 amino acids, no more than 24 amino acids or no more than 17 amino acids. In some embodiments, the peptide consists of 33 amino acids. In some embodiments, the peptide consists of 27 amino acids. In other embodiments, the peptide consists of 24 amino acids. In other embodiments, the peptide consists of 17 amino acids. In some embodiments, the immunogenic fragment of SEQ ID NO: 3 comprises position 119 to position 126, position 120 to position 127 or position 121 to position 128 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of SEQ ID NO: 3 comprises position 119 to position 130, position 120 to position 131 , position 121 to position 132 of SEQ ID NO: 3. In other embodiments, the fragment comprises position 119 to position 133, position 120 to position 134, position 121 to position 135 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment or the peptide has a glycine residue at the C-terminus thereof. The glycine residue at the C-terminus may be a glycine residue which occurs naturally in the amino acid sequence of mutTGFpR2, or it may be a glycine residue which has been artificially added to the C-terminus of the peptide.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution consists of position 119 to position 126, position 120 to position 127 or position 121 to position 128 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment consists of position 119 to position 130, position 119 to position 133, position 120 to position 131, position 120 to position 134, position 121 to position 132 or position 121 to position 135 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment starts at position one, two or three from the N-terminus of the peptide. In some embodiments, the immunogenic fragment is the N-terminus of the peptide. In some embodiments, position 121 of SEQ ID NO: 3 is glycine.

In some embodiments, the peptide comprises an immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution wherein the immunogenic fragment consists of position 119 to position 126, position 119 to position 130, position 119 to position 133, position 120 to position 127, position 120 to position 131, position 120 to position 134, position 121 to position 128, position 121 to position 132, position 121 to position 135 of SEQ ID NO: 3, wherein position 121 of SEQ ID NO: 3 is glycine, and wherein the peptide has at least 94% sequence identity to SEQ ID NO: 2 outside of the immunogenic fragment and comprises no more than 33 amino acids. In some embodiments, the peptide comprises an immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution wherein the immunogenic fragment consists of position 119 to position 126, position 119 to position 130, position 119 to position 133, position 120 to position 127, position 120 to position 131, position 120 to position 134, position 121 to position 128, position 121 to position 132, position 121 to position 135 of SEQ ID NO: 3, wherein position 121 of SEQ ID NO: 3 is glycine, and wherein the peptide has 100% sequence identity to SEQ ID NO: 2 outside of the immunogenic fragment and comprises no more than 33 amino acids. In some embodiments, the immunogenic fragment is the N-terminus of the peptide. In some such embodiments, the peptide consists of 33 amino acids. In some embodiments, the peptide consists of 27 amino acids, and the peptide may consist of the amino acid sequence of SEQ ID NO: 17. Peptides consisting of the amino acid sequence of SEQ ID NO: 17 are referred to herein as “fsp17”. In other embodiments, the peptide consists of 24 amino acids, and the peptide may consist of the amino acid sequence of SEQ ID NO: 10. Peptides consisting of the amino acid sequence of SEQ ID NO: 10 are referred to herein as “fsp2”. In other embodiments, the peptide consists of 17 amino acids, and the peptide may consist of the amino acid sequence SEQ ID NO: 14. Peptides consisting of the amino acid sequence of SEQ ID NO: 14 are referred to herein as “fsp6a”.

In some embodiments, the peptide comprises an immunogenic fragment consisting of SEQ ID NO: 14 and the peptide comprises one or more additional amino acids at the C-terminus of the fragment. For example, the peptide may comprise one, two, three, four, five, six, seven, eight, nine or 10 additional amino acids at the C-terminus of the fragment. In some embodiments, the immunogenic fragment consisting of SEQ ID NO: 14 is the N-terminus of the peptide. In some embodiments, the fragment consisting of SEQ ID NO: 14 is the N-terminus of the peptide and the peptide comprises seven additional amino acids at the C-terminus of the fragment. In some embodiments, the fragment consisting of SEQ ID NO: 14 is the N-terminus of the peptide and the peptide comprises 10 additional amino acids at the C-terminus of the fragment. In other embodiments, the fragment consisting of SEQ ID NO: 14 is the N-terminus of the peptide and the peptide consists of seven additional amino acids at the C-terminus of the fragment. In some embodiments, the fragment consisting of SEQ ID NO: 14 is the N-terminus of the peptide and the peptide consists of 10 additional amino acids at the C-terminus of the fragment. In some embodiments, the one or more additional amino acids have at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or has 100%, sequence identity to the corresponding amino acids of SEQ ID NO: 2, and, preferably, have at least 95% or 100% sequence identity to the corresponding amino acids of SEQ ID NO: 2.

In some embodiments, the first peptide consists of an acetate salt of SEQ ID NO: 10.

Fsp4

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 135, but not position 121 , of SEQ ID NO: 3. In some embodiments, the peptide comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or has 100%, sequence identity to SEQ ID NO: 2 outside of the immunogenic fragment. In some embodiments, the peptide comprises no more than 20 amino acids, while in other embodiments the peptide consists of 20 amino acids. In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 133 to position 144, position 134 to position 145 or position 135 to position 146 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution comprises position 133 to position 147, position 134 to position 148 or position 135 to position 149 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution consists of position 133 to position 144, position 133 to position 147, position 134 to position 145, position 134 to position 148, position 135 to position 146 or position 135 to position 149 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution starts at position one, two or three from the N-terminus of the peptide. In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution is the N-terminus of the peptide. In some embodiments, position 135 of SEQ ID NO: 3 is glycine. In some embodiments, the immunogenic fragment or the peptide has a glycine residue at the C-terminus thereof. The glycine residue at the C-terminus may be a glycine residue which occurs naturally in the amino acid sequence of mutTGFpR2, or it may be a glycine residue which has been artificially added to the C-terminus of the peptide.

In some embodiments, the peptide comprises an immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) having an amino acid substitution wherein the fragment consists of position 133 to position 144, position 133 to position 147, position 134 to position 145, position 134 to position 148, position 135 to position 146 or position 135 to position 149 of SEQ ID NO: 3, wherein position 135 of SEQ ID NO: 3 is glycine, and wherein the peptide has 100% sequence identity to SEQ ID NO: 2 outside of the fragment and comprises no more than 20 amino acids. In some embodiments, the immunogenic fragment is the N-terminus of the peptide. In some embodiments, the peptide consists of 20 amino acids. In some embodiments, the peptide consists of the amino acid sequence of SEQ ID NO: 12, and such peptides are referred to herein as “fsp4”.

Fspla & fsplb

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) comprises at least 8 consecutive amino acids of SEQ ID NO: 8 or comprises at least 8 consecutive amino acids of SEQ ID NO: 3 including at least position 135 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment comprises at least 9 consecutive amino acids of SEQ ID NO: 8 or comprises at least 9 consecutive amino acids of SEQ ID NO: 3 including position 135 of SEQ ID NO: 3. In some embodiments, peptide comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or has 100%, sequence identity to SEQ ID NO: 2 outside of the immunogenic fragment. In some embodiments, the immunogenic fragment or peptide has a glycine residue at the C-terminus thereof. The glycine residue at the C-terminus may be a glycine residue which occurs naturally in the amino acid sequence of mutTGFpR2, or it may be a glycine residue which has been artificially added to the C-terminus of the peptide.

In some embodiments, the peptide capable of inducing an immune response against mutTGFpR2 (SEQ ID NO: 2) comprises at least s consecutive amino acids of SEQ ID NO: 8 or comprises at least 8 consecutive amino acids of SEQ ID NO: 3 including at least position 135 of SEQ ID NO: 3. In some embodiments, the peptide comprises 9 consecutive amino acids of SEQ ID NO: 8 or comprises 9 consecutive amino acids of SEQ ID NO: 3 including position 135 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment consists of 9 consecutive amino acids of SEQ ID NO: 8 or consists of at least 9 consecutive amino acids of SEQ ID NO: 3 including position 135 of SEQ ID NO: 3.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) comprises positions 10 to 17 or positions 11 to 18 of SEQ ID NO: 8. In some embodiments, the immunogenic fragment comprises positions 10 to 18 of SEQ ID NO: 8. In some embodiments, the immunogenic fragment comprises the amino acid sequence of SEQ ID NO: 15. In some embodiments, the immunogenic fragment consists positions 10 to 18 of SEQ ID NO: 8, and has the amino acid sequence of SEQ ID NO: 15. In some embodiments, the peptide consists of the amino acid sequence of SEQ ID NO: 15, and such peptides are referred to herein as “fspla”.

In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) comprises at least 8 amino acids of SEQ ID NO: 3 including position 135 of SEQ ID NO: 3, and, therefore, comprises an amino acid substitution compared with the naturally-occurring amino acid sequence of mutTGFpR2 (SEQ ID NO: 2). In some embodiments, the immunogenic fragment of mutTGFpR2 (SEQ ID NO: 2) comprises positions 129 to 136 or positions 130 to 137 of SEQ ID NO: 3. In some embodiments, the immunogenic fragment comprises positions 129 to 137 of SEQ ID NO: 3. In some embodiments, the amino acid at position 135 of SEQ ID NO: 3 is glycine. In some embodiments, the immunogenic fragment comprises the amino acid sequence of SEQ ID NO: 16. In some embodiments, the peptide consists of the amino acid sequence of SEQ ID NO: 16, and such peptides are referred to herein as “fsplb”.

As explained in Example 2, it is predicted that the amino acid sequence of SEQ ID NO: 15 or SEQ ID NO: 16 is immunogenic in view of the difference in immunogenicity of fsp6 (SEQ ID NO: 13) and fsp7 (SEQ ID NO: 22), and the similarities and differences between these amino acid sequences.

Second peptide (ASTE1)

The peptide derived from mutASTEI (SEQ ID NO: 5) is also referred to herein as “the second peptide”.

In some embodiments, in the peptide capable of inducing an immune response against a ASTE1 -1a frameshift mutant protein (mutASTEI; SEQ ID NO: 5), the immunogenic fragment comprises at least 8 consecutive amino acids of SEQ ID NO: 19. In some embodiments, the immunogenic fragment comprises at least 9 consecutive amino acids of SEQ ID NO: 19. In some embodiments, the immunogenic fragment comprises at least 10 consecutive amino acids of SEQ ID NO: 19. In some embodiments, the immunogenic fragment comprises at least 12 consecutive amino acids of SEQ ID NO: 18. In some embodiments, the immunogenic fragment comprises at least 15 consecutive amino acids of SEQ ID NO: 19. In some embodiments, the immunogenic fragment comprises at least 20 consecutive amino acids of SEQ ID NO: 19. In other embodiments, the immunogenic fragment comprises at least 25 consecutive amino acids of SEQ ID NO: 19.

In some embodiments, the immunogenic fragment comprises no more than 25 consecutive amino acids of SEQ ID NO: 19. In some embodiments, the peptide comprises no more than 31 consecutive amino acids of SEQ ID NO: 20.

In some embodiments, the peptide comprises at least 10 amino acids. In some embodiments, the peptide comprises at least 12 amino acids. In some embodiments, the peptide comprises at least 15 amino acids. In some embodiments, the peptide comprises 20 amino acids. In other embodiments, the peptide comprises at least 25 amino acids.

In some embodiments, the peptide comprises no more than 40 amino acids. In some embodiments, the peptide comprises no more than 31 amino acids. In other embodiments, the peptide comprises no more than 25 amino acids.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises no more than 8 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4). In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises no more than 5 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4). In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises no more than 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4). In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) has only three amino acids from the wild-type sequence of ASTE1 (SEQ ID NO: 4). Preferably, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) does not contain any amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4).

In some embodiments, the peptide capable of inducing an immune response against mutASTEI (SEQ ID NO: 5) comprises no more than 8 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4). In some embodiments, the peptide does not contain more than 5 amino acids from the wild-type sequence of ASTE1 (SEQ ID NO: 4). In some embodiments, the peptide does not contain more than 3 amino acids from the wild-type sequence of ASTE1 (SEQ ID NO: 4). In some embodiments, the peptide contains only 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4). Preferably, the peptide does not contain any amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4).

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) or the peptide capable of inducing an immune response against mutASTEI (SEQ ID NO: 5) comprises positions 631 and 632 of SEQ ID NO: 5, wherein the amino acid at position 631 of SEQ ID NO: 5 corresponds to position 631 of wild-type ASTE1 (SEQ ID NO: 4) and the amino acid at position 632 of SEQ ID NO: 5 is the first amino acid of the amino acid sequence resulting from the frameshift mutation in mutASTEI (SEQ ID NO: 5). In some embodiments, the immunogenic fragment or peptide comprises position 630 to position 632, position 629 to position 632, position 628 to position 632, or position 627 to position 632 of SEQ ID NO: 5. In some embodiments, the immunogenic fragment or peptide has only 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4), which are positions 629, 630 and 631 of SEQ ID NO: 4 (i.e. positions 629, 630 and 631 of SEQ ID NO: 5). In particular, Figures 10 and 11 show that a peptide (fsp15; SEQ ID NO: 20) having only 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4) is capable of inducing a T-cell response, and therefore is immunogenic, when administered alone or in a peptide mixture.

When an immunogenic fragment or a peptide comprises one or more amino acids from the wildtype amino acid sequence of ASTE1 (SEQ ID NO: 4), these amino acids are preferably at the N-terminus of the immunogenic fragment or peptide. In some embodiments, the immunogenic fragment has only 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4), and these are at the N-terminus of the immunogenic fragment. In some embodiments, the peptide has only 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4), and these are at the N-terminus of the peptide.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises position 1 to position 8, position 2 to position 9, position 3 to position 10, position 4 to position 11 , position 5 to position 12, position 6 to position 13, position 7 to position 14, position 8 to position 15, position 9 to position 16, position 10 to position 17, position 11 to position 18, position 12 to position 19, position 13 to position 20, position 14 to position 21 , position 15 to position 22, position 16 to position 23, position 17 to position 24 or position 18 to position 25 of SEQ ID NO: 19. In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises position 1 to position 9 or position 8 to position 16 of SEQ ID NO: 19.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises position 1 to position 10, position 2 to position 11 , position 3 to position 12, position 4 to position 13, position 5 to position 14, position 6 to position 15, position 7 to position 16, position 8 to position 17, position 9 to position 18, position 10 to position 19, position 11 to position 20, position 12 to position 21, position 13 to position 22, position 14 to position 23, position 15 to position 24 or position 16 to position 25 of SEQ ID NO: 19.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises position 1 to position 15, position 2 to position 16, position 3 to position 17, position 4 to position 18, position 5 to position 19, position 6 to position 20, position 7 to position 21, position 8 to position 22, position 9 to position 23, position 9 to position 24 or position 10 to position 25 of SEQ ID NO: 19.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises position 1 to position 8, position 1 to position 9 or position 1 to position 15 of SEQ ID NO: 19, and the immunogenic fragment is the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises position 4 to position 11 or position 4 to position 18 of SEQ ID NO: 19, and the immunogenic fragment starts at position four from the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises position 8 to position 15 or position 8 to position 16 of SEQ ID NO: 19, and the immunogenic fragment starts at position eight from the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises position 9 to position 16 or position 9 to position 23 of SEQ ID NO: 19, and the fragment starts at position nine from the N-terminus of the peptide. In some embodiments, the immunogenic fragment comprises position 11 to position 18 or position 11 to position 25 of SEQ ID NO: 19, and the immunogenic fragment ends at position eight from the C-terminus of the peptide.

In some embodiments, the immunogenic fragment comprises the amino acid sequence of SEQ ID NO: 19. In some embodiments, the immunogenic fragment consists of the amino acid sequence of SEQ ID NO: 19. In other embodiments, the peptide capable of inducing an immune response against mutASTEI (SEQ ID NO: 5) consists of the amino acid sequence of SEQ ID NO: 19. The peptide consisting of the sequence of SEQ ID NO: 19 is referred to herein as “fsp8”. In particular, Figure 5 shows that a peptide mixture containing fsp8 is immunogenic, as the peptide mixture induces a T-cell response in three out of four donors. In addition, Figures 6- 9 show that fsp8 alone induces a T-cell response even after only one round of stimulation with a peptide mixture containing fsp8. Thus, fsp8 is immunogenic.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) comprises a glycine residue at the C-terminus thereof. In some embodiments, the peptide capable of inducing an immune response against mutASTEI (SEQ ID NO: 5) comprises a glycine residue at the C-terminus thereof. Figures 10 and 11 show that a peptide of mutASTEI (SEQ ID NO: 5), having a glycine residue that the C-terminus thereof, is capable of inducing T-cell response whether administered as a single peptide composition or as part of a peptide mixture. The glycine residue at the C-terminus of the immunogenic fragment or the peptide may be a glycine residue which occurs naturally in the amino acid sequence of mutASTEI , or it may be a glycine residue which has been artificially added to the C-terminus of immunogenic fragment or the peptide.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) or the peptide capable of inducing an immune response against mutASTEI (SEQ ID NO: 5) comprises 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4) at the N- terminus thereof, and a glycine residue at the C-terminus thereof. In some embodiments, the immunogenic fragment or the peptide has only 3 amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4), which are at the N-terminus of the immunogenic fragment or peptide, and the immunogenic fragment or peptide has a glycine residue at the C-terminus thereof. In some embodiments, the immunogenic fragment or the peptide does not comprise any amino acids from the wild-type amino acid sequence of ASTE1 (SEQ ID NO: 4), and the immunogenic fragment or peptide has a glycine residue at the C-terminus thereof.

In some embodiments, the immunogenic fragment of mutASTEI (SEQ ID NO: 5) consists of the amino acid sequence of SEQ ID NO: 20. In some embodiments, the peptide capable of inducing an immune response against mutASTEI (SEQ ID NO: 5) consists of the amino acid sequence of SEQ ID NO: 20. The peptide consisting of the amino acid sequence of SEQ ID NO: 20 is referred to herein as “fsp15”. In particular, and as mentioned above, Figures 10 and 11 show that a peptide mixture containing fsp15, and fsp15 alone, is immunogenic, as the peptide mixture and the peptide alone induce a T-cell response. Thus, fsp15 is immunogenic.

In some embodiments, the second peptide is an acetate salt. In some embodiments, the second peptide consists of an acetate salt of SEQ ID NO: 19. Peptide mixtures

The peptide mixtures of the invention contain a peptide derived from mutTGFpR2 as described above (i.e. the first peptide), a peptide derived from mutASTEI as described above (i.e. a second peptide) and a peptide derived from TAFi as described above (i.e. a third peptide). Each of these first, second and third peptides is each independently any of the above-described first, second and third peptides (i.e. any combination of the above-described first, second and third peptides).

In some embodiments, the peptide mixture comprises at least 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15 or 16 different peptides. In some embodiments, the peptide mixture comprises no more than 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15 or 16 different peptides. In some embodiments, the peptide mixture comprises 3 different peptides. In some embodiments, the peptide mixture comprises 5 different peptides. In some embodiments, the peptide mixture comprises 10 different peptides. In some embodiments, the peptide mixture comprises no more than 10 different peptides. In some embodiments, the peptide mixture consists of only the first, second and third peptides.

In some embodiments, the first peptide comprises the amino acid sequence of one of SEQ ID NOs: 8-18 and the second peptide comprises the amino acid sequence of SEQ ID NO: 19 or 20. In these embodiments, the first peptide may comprise no more than 33, 27, 24, 20, 17 or 9 amino acids, and the second peptide may comprise no more than 31 , 30 or 25 amino acids. In some embodiments, the first peptide consists of the amino acid sequence of one of SEQ ID NOs: 8-18, and the second peptide consists of the amino acid sequence of SEQ ID NO: 19 or 20. In each of the embodiments in this paragraph, the third peptide may be any of the abovedescribed peptides derived from mutTAFi .

In some embodiments, the first peptide comprises the amino acid sequence of one of SEQ ID NOs: 8-18, the second peptide comprises the amino acid sequence of SEQ ID NO: 19 or 20, and the third peptide comprises the amino acid sequence of SEQ ID NO: 21. In some embodiments, the first peptide comprises the amino acid sequence of one of SEQ ID NOs: 8- 18, the second peptide comprises the amino acid sequence of SEQ ID NO: 19 or 20, and the third peptide consists of the amino acid sequence of SEQ ID NO: 21.

In some embodiments, each of the first, second and third peptides is a lyophilisate. In some embodiments, each of the first, second and third peptides is an acetate salt. In some embodiments, the first peptide comprises the amino acid sequence of SEQ ID NO: 10, the second peptide comprises the amino acid sequence of SEQ ID NO: 19, and the third peptide comprises the amino acid sequence of SEQ ID NO: 21. In some embodiments, the peptide mixture consists of only these three peptides. In some of these embodiments, each of the first, second and third peptides is an acetate salt.

In some embodiments, the first peptide consists of the amino acid sequence of SEQ ID NO: 10, the second peptide consists of the amino acid sequence of SEQ ID NO: 19, and the third peptide consists of the amino acid sequence of SEQ ID NO: 21. In some embodiments, the peptide mixture consists of only these three peptides. These peptide mixtures, where the first, second and third peptides consist of the amino acid sequences of SEQ ID NOs: 10, 19 and 21 , respectively, and are the only peptides in the peptide mixture, are referred to herein as “FMPV3”. In some of these embodiments, each of the first, second and third peptides is an acetate salt.

The peptide mixtures of the invention, and particularly FMPV3, are expected to provide immunogenic peptides which encompass a broad range of epitopes, thereby providing a universal vaccine which targets a broad range of HLA alleles. As discussed above, about 15% of all CRCs are MSI-H, and MSI has also been reported in glioblastomas, lymphomas, stomach, urinary tract, ovarian and endometrial tumours; it has been reported that each of TAFip, ASTE1 and TGFPR2 is independently mutated in more than 75% of MSI CRCs; about 22% of stomach (gastric) cancers are MSI-H; frameshift mutations in TGFpR2 are reported to be found in about 15% of all CRCs, about 44% of all MSI-H cancers, and in particular in about 58% of MSI-H colon cancers and about 80% of MSI-H stomach cancers; and frameshift mutations in ASTE1 are found in about 45% of all MSI-H cancers. Therefore, FMPV3 is expected to be useful for the treatment of a significant population of cancer patients. In addition, and as also discussed above, the Lynch syndrome population is at high risk of developing cancer and people with HNPCC have a somatic mutation, which is expected to develop into a frameshift mutation; 99% of hereditary CRCs (HNPCC) are MSI-H; of the MSI-H HNPCC patients, about 90% have a frameshift mutation in the protein TGFPR2; and ASTE1 and TAF1B are reported to be present in about 90% and 75%, respectively, in MSI-colorectal cancer and in about 85% and 50% in endometrial cancer. Therefore, the peptide mixtures of the present invention, and particularly FMPV3, are expected to be useful as a prophylactic vaccine for Lynch syndrome patients, who are at risk of developing a MSI-associated cancer. The peptide mixtures may contain the peptides in equal or different proportions. In some embodiments, the first, second and third peptides are present in the mixture in equal proportions, i.e. each peptide comprises 33.3% of the peptide component of the peptide mixture. In other embodiments, there is a greater proportion of the first peptide in the peptide mixture than the sum of the second peptide and the third peptide. For example, the first peptide may comprise at least 55%, at least 60%, at least 70%, at least 80% or at least 90% of the peptide component of the peptide mixture. In alternative embodiments, there is a greater proportion of the second peptide in the peptide mixture than the sum of the first peptide and third peptide. For example, the second peptide may comprise at least 55%, at least 60%, at least 70%, at least 80% or at least 90% of the peptide component of the peptide mixture. In embodiments there is a greater proportion of the third peptide than the sum of the first peptide and second peptide. For example, the third peptide may comprise at least 55%, at least 60%, at least 70%, at least 80% or at least 90% of the peptide component of the peptide mixture. For example, each of the first, second and third peptide may independently comprise at least 1%, at least 5%, at least 10%, at least 20% at least 30%, at least 40%, at least 50%, at least 60%, at least 60%, at least 70%, at least 80% or at least 90% of the peptide component of the peptide mixture.

Nucleic acids

In another aspect of the present invention, there is provided at least one nucleic acid molecule or molecules which individually or collectively comprise nucleotide sequences encoding the first, second and third peptides in the peptide mixtures of the disclosures above, or the nucleic acid molecule comprises a nucleotide sequence encoding the third peptide. Thus, in some embodiments, each nucleic acid molecule encodes one, two or three of the peptides in the peptide mixture of the disclosures above. In some embodiments, each nucleic acid molecule encodes only one of the peptides of the peptide mixtures disclosed above. In some embodiments, each nucleic acid molecule encodes 2 or 3 of the peptides of the peptide mixtures disclosed above.

There is also provided a mixture of nucleic acid molecules (also referred to herein as a “nucleic acid mixture”), wherein each nucleic acid molecule of the mixture comprises a nucleotide sequence which encodes a different peptide of a peptide mixture according to the disclosures above. Thus, the mixture of nucleic acid molecules collectively encodes the peptide mixture of the disclosures above. In some embodiments, the at least one nucleic acid molecule, and the mixtures of nucleic acid molecules, are used to synthesise the peptides and peptides mixtures of the disclosures above. For example, the third peptide described above, or one or more peptides of the peptide mixtures described above, may be synthesised by administering one or more nucleic acid molecule to a subject, whereupon each nucleic acid molecule is expressed by the subject, thereby giving rise to one or more peptide in situ. The peptide(s) produced then elicits an immune response in the subject. In another example, the nucleic acid molecule(s) may be used to synthesise the third peptide described above, or one or more peptide of the peptide mixtures described above, in vitro, by transforming or transfecting a host cell with the nucleic acid molecule, such that the host cell expresses the nucleic acid molecule to produce the peptide. The peptide is then recovered and purified. In some embodiments, the third peptide described above, and the peptides of the peptide mixtures described above, are produced by chemical synthesis, using methods well known in the art.

T-cell receptors

In another aspect of the invention, there is provided a T-cell receptor, or an antigen-binding fragment thereof, specific for a peptide according to the disclosures above, when presented on an MHC molecule.

In some embodiments, the T-cell receptor is an op T-cell receptor, or the antigen-binding fragment of the T-cell receptor is an antigen-binding fragment of an op T-cell receptor. In these embodiments, the T-cell receptor, or antigen-binding fragment thereof, is specific for a peptide according to the disclosures herein when presented on an MHC molecule.

In some embodiments, the T-cell receptor is a y<5 T-cell receptor, or the antigen-binding fragment of the T-cell receptor is an antigen-binding fragment of a y<5 T-cell receptor. In these embodiments, the T-cell receptor does not necessarily require presentation of the peptide on an MHC molecule in order to recognise the peptide.

T-cells and T-cell mixtures

In another aspect of the present invention, there is provided a T-cell specific for the third peptide (i.e. a peptide derived from mutTAFip) according to the disclosures above.

There is further provided a T-cell mixture comprising T-cells specific for each of the peptides in the peptide mixtures of the disclosures above. Thus, the T-cell mixture comprises first, second and third T-cells specific for first, second and third peptides, respectively, wherein the first peptide is a mutTGFpR2 peptide according to the disclosures above, the second peptide is a mutASTEI peptide according to the disclosures above, and the third peptide is a mutTAFip peptide according to the disclosures above.

In some embodiments, the T-cell, or each of the T-cells in the T-cell mixture, is a nontransfected T-cell.

The T-cell and T-cell mixture may be ex vivo and may be produced by stimulating, ex vivo, at least one reactive T-cell with a peptide or a peptide mixture according to the disclosures above.

Where the T-cell receptor of any T-cell disclosed herein is an op T-cell receptor, then the T-cell receptor is specific for the peptide when presented on an MHC molecule. Where the T-cell receptor of any T-cell disclosed herein is a y<5 T-cell receptor, then the T-cell receptor does not necessarily require presentation of the peptide on an MHC molecule in order to recognise the peptide.

Vector & Host Cell

In another aspect of the present invention, there is provided a vector comprising a nucleic acid molecule comprising a nucleotide sequence according to the disclosures above. The nucleotide sequence, therefore, encodes the third peptide as disclosed above, or at least one of the peptides in the peptide mixtures as disclosed above. In some embodiments, the vector comprises a nucleic acid molecule comprising a nucleotide sequence which encodes all of the peptides of a peptide mixture according to the disclosure above.

In some embodiments, the vector is a DNA vector or a RNA vector.

In a further aspect, there is provided a host cell comprising a vector as described above. The host cell is transfected or transformed with the vector, such that the host cell expresses the nucleic acid molecule(s) encoded by the vector. The host cell may be any cell type that is capable of being transfected with a vector and expressing the vector. In some embodiments, the host cell is a plant cell, an animal cell, a micro-organism, or a yeast cell. In some embodiments, the host cell is a dendritic cell.

In some embodiments, the host cell may contain more than one vector, wherein each vector comprises a nucleic acid molecule comprising a nucleotide sequence encoding a different peptide as described above. Thus, the host cell may comprise multiple vectors, each encoding a different peptide, such that the host cell expresses more than one type of nucleic acid molecule and, therefore, more than one peptide.

Pharmaceutical Compositions

Pharmaceutical compositions comprising the peptides, peptide mixtures, T-cell receptors or antigen-binding fragments thereof, T-cells, T-cell mixtures, nucleic acid molecule(s), vectors or host cells described above are also provided. Such pharmaceutical compositions may also comprise at least one pharmaceutically acceptable carrier, diluent and/or excipient. For example, the pharmaceutically acceptable carrier, diluent and/or excipient may be saline or sterilised water. In some embodiments, the pharmaceutical composition further comprises one or more additional active ingredients and/or adjuvants. In certain embodiments, the pharmaceutical composition may further comprise one or more ingredients therapeutically effective for the same disease indication. In one embodiment, the pharmaceutical composition of the present invention may further comprise one or more further chemotherapeutic agents, one or more cancer vaccines, one or more antibodies, one or more small molecules and/or one or more immune stimulants (for example, cytokines). In some embodiments, the peptide, peptide mixture, T-cell receptor or antigen-binding fragment thereof, T-cell, T-cell mixture, nucleic acid molecule(s), vector, host cell or the pharmaceutical composition may be used in combination with other forms of immunotherapy, including other cancer vaccines. In some embodiments, the peptide, peptide mixture, T-cell receptor or antigen-binding fragment thereof, T-cell, T-cell mixture, nucleic acid, vector, host cell or the pharmaceutical composition is used in combination with one or more cancer vaccines derived from a different cancer antigen.

Use

Peptides, peptide mixtures, T-cell receptors, T-cells, T-cell mixtures, nucleic acid molecules, vectors, host cells and pharmaceutical composition disclosed above are for use medicine, preferably in the treatment and/or prophylaxis of cancer, and in particular cancer associated with MSI. In some embodiments, the treatment and/or prophylaxis is of a cancer associated with a frameshift mutation, preferably a -1a frameshift mutation in one or more of TGFPR2, ASTE1 and TAFip. In particular, it is common for cancer patients who have a frameshift mutation to have more than one frameshift mutations, as the underlying cause of these cancers is failure of DNA mismatch repair (MMR). Preferably, the treatment and/or prophylaxis of cancer is in humans. In particular, about 15% of all CRCs, and about 44% of all MSI-H cancers, have a frameshift mutation in TGFPR2. In addition, TAFip, ASTE1 and TGFPR2 are three of the four most frequently mutated genes in MSI CRCs, and a frameshift mutation in each of these genes is independently found in 75% of MSI-H CRCs. Moreover, a frameshift mutation in ASTE1 is found about 45% of all MSI-H cancers. The treatment and/or prophylaxis of cancer may be in a Lynch syndrome patient. As discussed above, Lynch syndrome patients are at high risk of developing cancer, and 99% of hereditary CRCs (HNPCC) are MSI-H. Thus, the present invention provides an effective treatment and/or prophylactic for a large proportion of cancers.

The cancer may be colorectal cancer, stomach cancer or endometrial cancer, preferably MSI- colorectal cancer, MSI-stomach cancer or MSI-endometrial cancer. The colorectal cancer or MSI-colorectal cancer may be colon cancer or rectal cancer. The peptides, peptide mixtures, T- cell receptors, T-cells, T-cell mixtures, nucleic acid molecules, vectors and host cells may be used for the treatment and/or prophylaxis of more than one of these types of cancer. In particular, the peptides, peptide mixtures, T-cell receptors, T-cells, T-cell mixtures, nucleic acid molecules, vectors and host cells of the disclosures above can be used to treat all MSI- colorectal cancers and a large proportion of all MSI-H cancers, and can be used as a prophylactic vaccine for at least Lynch syndrome patients. Thus, the present invention provides an effective treatment and/or prophylactic for a large proportion of cancers, particularly colorectal cancer, stomach cancer and endometrial cancer, and more particularly, hereditary colorectal cancer.

In some embodiments, peptides, peptide mixtures, T-cell receptors, T-cells, T-cell mixtures, nucleic acid molecules, vectors and host cells are used for the prevention of cancer, preferably in Lynch syndrome patients.

In some embodiments, a peptide mixture comprising a first peptide which comprises the amino acid sequence of one of SEQ ID NOs: 8-18, a second peptide comprising the amino acid sequence of SEQ ID NO: 19 or 20, and a third peptide comprising the amino acid sequence of SEQ ID NO: 21 is particularly useful for the treatment and/or prevention of cancer, preferably the prevention of cancer. The treatment and/or prevention, and preferably prevention of cancer, may be in a Lynch syndrome patient.

In some embodiments, FMPV3 is particularly useful for the treatment and/or prevention of cancer, preferably the prevention of cancer. The treatment and/or prevention, and preferably prevention of cancer, may be in a Lynch syndrome patient.

The T-cell, or the T-cells in the T-cell mixture, for use in the treatment and/or prophylaxis of cancer may be autologous or allogenic. For example, heterologous T-cells may be administered to a patient where the T-cells are from a donor having the same or similar HLA repertoire as the patient.

The peptide, peptide mixture, vector, host cell or pharmaceutical composition of the invention may be administered to a subject by any suitable delivery technique known to those skilled in the art. For example, among other techniques, the peptide, peptide mixture or pharmaceutical composition may be administered to a subject by injection, in the form of a solution, in the form of liposomes or in dry form (for example, in the form of coated particles, etc). The host cell may be administered, for example, by transfusion. The vector may be administered, for example, by injection subcutaneously or into the tumour. In some embodiments, the peptide, peptide mixture or pharmaceutical composition may be administered in an amount, for example, of between 1 pg and 1g of each peptide once every three days, once a week, once a month, once every three months, once every four months or once every six months. In some embodiments, the net amount of each peptide per dose is 60nM. For example, for intradermal injection, each peptide may be present in a volume of 0.1ml at a concentration of 0.6mM.

In some embodiments, the peptide or peptide mixture is administered with an adjuvant or immune stimulator, such as GM-CSF. In embodiments using GM-CSF, this may be any GM- CSF, for example, glycosylated GM-CSF or non-glycosylated GM-CSF. GM-CSF may be administered in an amount of between 0.5 and 120 pg/ m ² , between 1 and 120 pg/ m ² , between 2 and 115 pg/ m ² , between 3 and 110 pg/ m ² , between 4 and 105 pg/ m ² , between 5 and 100 pg/ m ² , between 6 and 95 pg/ m ² , between 7 and 90 pg/ m ² , between 48 and 85 pg/ m ² , between 9 and 80 pg/ m ² , between 10 and 75 pg/ m ² , between 11 and 70 pg/ m ² , between 12 and 65 pg/ m ² , between 13 and 60 pg/ m ² , between 14 and 55 pg/ m ² , between 15 and 50 pg/ m ² , between 16 and 45 pg/ m ² , between 17 and 40 pg/ m ² , or between 18 and 40 pg/ m ² of body surface area. In some embodiments, GM-CSF is administered at a dosage of between 1 pg and 200 pg, between 5 pg and 175 pg, between 5 pg and 150 pg, between 5 pg and 125 pg, between 5 pg and 100 pg, between 10 pg and 100 pg, between 20 pg and 90 pg, between 25 pg and 80 pg, between 25 pg and 70 pg, between 25 pg and 65 pg, or between 30 pg and 60 pg, per dose. In some embodiments, non-glycosylated GM-CSF is administered at a dosage of 30pg per dose. In other embodiments, glycosylated GM-CSF is administered at a dosage of 60pg dose. In embodiments where GM-CSF is administered by intradermal injection, the dose may be a 0.1ml solution containing GM-CSF at a concentration of 0.3mg/ml or 0.6mg/ml. In some embodiments, the peptide, peptide mixture or pharmaceutical composition may be administered in an amount, for example, of between 1pg and 1g of each peptide once every three days, once a week, once a month, once every three months, once every four months or once every six months.

The T-cell receptors of the present invention may be transfected into T-cells of a patient having a HLA allele matching the HLA allele for which the T-cell receptor is specific using methods known in the art. In particular, T-cells are obtained from the patient, the T-cells are transfected with a vector encoding the T-cell receptors, and the transfected T-cells are re-introduced to the patient.

The T-cells and T-cell mixtures of the present invention may be administered by intra-venous injection and/or infusion, and may be administered in an amount, for example, of between 10 ⁶ and 10 ¹² of each T-cell specific for a peptide of the peptide mixture or peptide once every month, once every two months, once every three months, once every six months or once a year. Preferably, the dosage is administered once every month for between 2 and 5 months and is subsequently administered less frequently.

The nucleic acid and mixture of nucleic acids of the present invention may be administered by intra-muscular injection and/or subcutaneous injection. Once administered, the nucleic acid, or any or each of the nucleic acids in the mixture of nucleic acids is optionally transcribed, and then translated, into a peptide which elicits an immune response.

Administration of a peptide or a peptide mixture of the present invention to a subject, or expression of the peptide or peptide mixture by a subject, elicits an immune response to the peptide or peptide mixture, in particular a T-cell mediated immune response. The peptide, or each peptide of the peptide mixture, may be processed by an antigen-presenting cell (APC) and may be presented on an MHC molecule, op T-cells are activated by binding of the T-cell receptor to a peptide presented on a MHC molecule by the APC, thereby resulting in an immune response against tumour cells having a mutation corresponding to that present in the administered peptide(s). y<5 T-cells do not necessarily require antigen processing or presentation of the antigen by MHC molecules.

In another aspect of the invention, there is provided a peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, a mixture of nucleic acid molecules or a pharmaceutical composition for use in a method of diagnosis of cancer and the selection of an appropriate treatment. The method comprises the steps of (i) identifying whether a cancer patient is MSI-H and/or has Lynch syndrome and, if so, (ii) selecting a peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture or pharmaceutical composition according to the disclosures above. In some embodiments, the method further comprises, in step (i), testing whether the patient has a frameshift mutation in one or more of the TGFPR2, ASTE1 and TAFip protein and, if so, selecting a peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture or pharmaceutical composition according to the disclosures above. In some embodiment, the frameshift mutation is a -1a frameshift mutation. In some embodiments, the method further comprises (iii) administering the selected peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture or pharmaceutical composition to the patient.

In another aspect of the present invention, there is provided a method of treating and/or preventing cancer comprising administering a peptide, peptide mixture, T-cell receptor, T-cell, T- cell mixture, at least one nucleic acid molecule, nucleic acid molecule or pharmaceutical composition according to the disclosures above to a patient in need thereof. In some embodiments, the method is a method of treatment of cancer and comprises the steps of (i) identifying a cancer patient as MSI-H and/or having Lynch syndrome, and (ii) administering a peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture or pharmaceutical composition according to the disclosures above to the patient. In some embodiments, the method is a method of preventing cancer and comprises the steps of (i) identifying a patient at risk of developing cancer, preferably a Lynch syndrome patient, and (ii) administering a peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid molecule or pharmaceutical composition according to the disclosures above to the patient. Any of these methods may further comprise, in step (i), the step of identifying that the patient has a frameshift mutation in one or more of the TGFPR2, ASTE1 and TAFip protein. In some embodiments, the frameshift mutation is a -1a frameshift mutation.

In another aspect of the present invention, there is provided a method of selecting a peptide mixture, a peptide, at least one nucleic acid molecule, nucleic acid mixture, vector, host cell, T- cell receptor, T-cell, T-cell mixture or a pharmaceutical composition for administration to a patient, comprising (i) identifying a Lynch syndrome patient, and (ii) selecting a peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture or pharmaceutical composition according to the disclosures above. In another aspect of the present invention, the peptide mixture, peptide, at least one nucleic acid molecule, nucleic acid mixture, vector, host cell, T-cell receptor, T-cell, T-cell mixture or pharmaceutical composition is for use in the manufacture of a medicament for the treatment and/or prophylaxis of a disease or condition. Preferably, the disease or condition is cancer, and may be any of the above-discussed cancers.

Kit

In another aspect of the invention, there is provided a kit that includes a peptide, a peptide mixture, a T-cell receptor, a T-cell, a T-cell mixture, at least one nucleic acid molecule, a nucleic acid mixture, a vector, a host cell and/or a pharmaceutical composition according to the disclosures above. The peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid, nucleic acid mixture, vector and/or host cell as such may be present in the kit, or the peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture, vector and/or host cell may be present as a pharmaceutical formulation. In some embodiments, the peptide, peptide mixture, T-cell receptor, T-cell, T-cell mixture, at least one nucleic acid molecule, nucleic acid mixture, vector, host cell and/or pharmaceutical composition may be packaged, for example in a vial, bottle, flask, which may be further packaged, for example, within a box, envelope or bag. In some embodiments, the kit comprises a peptide mixture, a T-cell mixture and/or nucleic acid mixture wherein the peptides of the peptide mixture, the T-cells of the T-cell mixture and/or the nucleic acid molecules of the nucleic acid mixture are provided in separate containers, such that the peptides, T-cells and/or nucleic acid molecules are mixed by the user.

Examples

Example 1 - Immunogenicity of the TGFBR2 peptides i) Materials

Table 1 : Materials

Fresh buffy coats from four healthy donors were obtained from a blood bank. ii) First in vitro stimulation of PBMC and T-cell proliferation

Day 1 :

PBMC:

Peripheral blood mononuclear cells (PBMC) isolated from fresh buffy coats from four healthy donors were counted and suspended in DC medium to 15*10 ⁶ cells/ml, and subsequently diluted with DC-medium to 4*10 ⁶ cells/ml (Table 1).

Table 2: Cell suspension and dilution

DC- medium: 500 ml CellGro DC medium (CellGenix) + 0.63 ml of 40mg/ml Gensumycin + 5 ml

1M HEPES buffer + 4ml of 200mg/ml Mucomyst/NAC

In-vitro stimulation:

Four 24-well plates were used for each donor, with 4*10 ⁶ cells per well (each well has a volume of 1 ml).

Peptide cocktail: Solution of peptides fsp2+fsp4, containing 10 .M of each peptide. 40 .l peptide solution was added to each well. The plates were incubated in a cell incubator for 14 days (37 °C, 5% CO2). IL-2 and IL-7 were added on day 3. The cells were inspected daily.

Day 14 - T cell Proliferation:

Test peptides: fsp2+fsp4 (SEQ ID NOs: 10 and 12), fsp1 (SEQ ID NO: 9), fsp2 (SEQ ID NO: 10), fsp3 (SEQ ID NO: 11), fsp4 (SEQ ID NO: 12), fsp5 (SEQ ID NO: 8).

Positive control: SEC3

Negative controls: T cells, T cells+APC (without addition of test peptides)

Mock: DMSO in PBS

Plate set up for T cell proliferation:

Cells and reagents were added to plate wells (in triplicate) as described in Tables 3 and 4 below. The total volume added to each well was 0.20ml.

• T cells (PBMC): 50 000 cells /well (0.25*10 ⁶ cells/ml)

• APC: Irradiated (30Gy, 8 minutes) autologous feeder cells: 50 000 cells /well

• Peptide (fspx): 0.2nmol peptide/well (each peptide), concentration: 10 .M peptide, (fsp was dissolved in DMSO before dilution to correct concentration)

Table 3: Plate 1 (96 wells) set up: Table 4: Plate 2 (96 wells) set up:

The plates were incubated in a cell incubator for 48 hours (37 °C, 5% CO2).

Day 16.

After incubation for 48 hours, 20pl 3H-tThymidine solution (5pCi/ml) was added to each well and the plates were incubated for approximately 17 hours (37 °C, 5% CO2).

Day 17.

After 17 hours the cells were harvested (Unifilters) and dried on the filters at 45°C until completely dry. After covering the bottom of the Unifilters with adhesive covers (delivered with the Unifilters) 25 pl micro scintillation liquid was added to each well, the plate was covered with TopSeal and 3H-Thymidine uptake was measured as counts per minute (CPM) using a microplate scintillation counter.

Proliferation results:

The T cell proliferation results after the first round of in vitro stimulation with the cocktail of fsp2 and fsp4 peptides are presented as stimulation index (SI) in Figure 1. Sl= mean CPM(triplicates) of (T cells+APC+test peptide(s)) divided by mean CPM (triplicates) of (T cells+APC). Sl> 1 indicates an increase in T-cell proliferation and SI > 2 is a clear sign of immunogenicity.

Hi) In vitro re-stimulation of PBMC and T-cell proliferation

PBMCs harvested after the first in vitro stimulation were re-stimulated in vitro according to the protocol set out above, with 2x10 ⁶ cells per well. T-cell proliferation was tested according to the protocol set out above.

Proliferation results:

The T cell proliferation results after a second round of in vitro stimulation with the cocktail of fsp2 and fsp4 peptides are presented as stimulation index (SI) in Figure 2.

Thus, Figures 1 and 2 show that the peptides fsp2 and fsp4, having an amino acid substitution, are immunogenic and can activate T-cells, and that the activated T-cells are cross-reactive for peptides of the naturally occurring -1a frameshifted TGFP2 protein. In addition, Figures 1-3 show that fsp1 and fsp5, which are peptides of the naturally-occurring -1a frameshifted TGFP2 protein, stimulated T-cells induced from PMBCs and, therefore, are immunogenic. Consequently, the modified peptides fsp2 (SEQ ID NO. 10) and fsp4 (SEQ ID NO. 12), as well as unmodified peptides fsp1 (SEQ ID NO: 9) and fsp5 (SEQ ID NO: 8), can be used to stimulate induction of TGF R2 frameshift mutant-specific T-cells.

Example 2 - Immunogenicity of fsp6 and fsp6a

A similar protocol to that set out in Example 1 was used to test the immunogenicity of fsp6 (SEQ ID NOs: 13) and fsp7 (SEQ ID NO: 22). Fsp2 (SEQ ID NO: 10; 10pM) was used to induce T- cells from PMBCs isolated from fresh buffy coats from four healthy donors. At day 14 after induction, a T-cell proliferation assay was carried out as in Example 4, using fsp2 (SEQ ID NO: 10), fsp6 (SEQ ID NO: 13) and fsp7 (SEQ ID NO: 22) as test peptides. The T-cell proliferation results after one round of in vitro stimulation are presented as stimulation index (SI) in Figure 4. In particular, Figure 4 shows that fsp6 is capable of activating T-cells, such that fsp6 is immunogenic and can be used as a vaccine or treatment against cancer. Figure 4 also shows that T-cells induced by fsp2 (SEQ ID NO: 10) are cross-reactive for peptides of the naturally- occurring TGFPR2 -1a frameshift protein which are shorter than fsp2 (SEQ ID NO: 10). It is also expected, in view of the results shown in Figures 2 and 3, that a peptide having the sequence of fsp6 (SEQ ID NO: 13) but having a C-to-G amino acid substitution corresponding to that in fsp2 is also immunogenic and is useful as a vaccine or treatment against cancer. In particular, as mentioned in Example 1 , Figure 3 shows that T-cells induced by fsp2 (SEQ ID NO: 10), which has a C-to-G amino acid substitution, are cross-reactive for peptides of the naturally-occurring TGFPR2 -1a frameshift mutant protein, such that the C-to-G amino acid substitution is immunologically acceptable. Thus, it is expected that fsp6a (SEQ ID NO: 14), which is identical to fsp6 (SEQ ID NO: 13) except for the same C-to-G amino acid substitution as fsp2 (SEQ ID NO: 10), will also be immunogenic.

Furthermore, Figure 4 shows that fsp6 (SEQ ID NO: 13) is less immunogenic than fsp2 (SEQ ID NO: 10), but that both fsp6 and fsp2 are much more immunogenic than fsp7 (SEQ ID NO: 21). Fsp6 has the same amino acid sequence as fsp2, except that fsp6 is truncated at the C- terminus compared to fsp2 and does not have a C-to-G amino acid substitution. Fsp7 has the same amino acid sequence as fsp2 but is truncated at the N-terminus compared to fsp2. In view of the difference in immunogenicity between these three peptides, shown in Figure 4, it is expected that at least one additional amino acid at the C-terminus of fsp6 is required in order to retain the immunogenicity of fsp2. In addition, it is expected that at least one additional amino acid at the N-terminus of fsp7 is required in order to increase its immunogenicity and for the peptide to comprise immunologically effective epitopes. Consequently, it is expected that fspla (LVRLSSCVP; SEQ ID NO: 15) is immunogenic, or is a significant element of an immunogenic peptide, as this peptide comprises a sequence shared by fsp6 and fsp7, with the addition of one amino acid at the C-terminus compared to fsp6 and one amino acid at the N-terminus compared to fsp7. Furthermore, as the C-to-G amino acid substitution has been shown to be immunologically acceptable, it is expected that fspla having a C-to-G amino acid substitution (i.e. fsplb; SEQ ID NO: 16) will also be immunogenic. of peptides and peptide mixtures i) Equipment

• Heraeus megafuge 2.0

• KOJAIR laminar flow hood KR-210 K-Safety

• CO2 incubator, Forma Scientific Model 3111

• FACSCanto ii) Reagents

• CellGro DC medium (Cat. no. 0020801-0500, CellGenix GmbH, Freiburg, Germany)

• HEPES 1M (Fischer scientific)

• Mucomyst/NAC (Meda AS, Asker, Norway)

• Gensumycin (Gibco, Life Technologies)

• IL-2 • rhlL-7

• SEC-3 superantigen 10mg/ml stock (Toxin Technology Inc, USA)

• Microplate 96-well, round bottomed (VWR International AS, Oslo, Norway)

• Topseal-A (Cat. No. 6005185, Nerliens Meszansky, Oslo, Norway)

• Microscient-0 scintillation liquid (Nerliens Meszansky, Oslo, Norway)

• 3H-Thymidine (Motebello Diagnostics, Oslo, Norway)

• RPMI-1640 with L-gutamin(Gibco, Life Technologies)

• Albunorm 200 g/l (20%) (Octapharma)

• Dimethylsulfoxide (DMSO) (Sigma Aldrich)

• Complete CellGro DC medium used for cell cultures

The following was added to 500ml of CellGro DC medium:

1. Gensumycin; 630 pL of 40 mg/ml stock solution (final concentration 0.05mg/ml)

2. HEPES buffer; 5 ml of 1M stock stock solution (final concentration 0.01 M)

3. Mucomyst/NAC; 4ml of 200 mg/ml stock solution (final concentration 1.6ml/ml)

Hi) Peptide stimulation of PBMC bulk cultures

PBMCs isolated from buffy coats from four healthy donors (obtained from a blood bank) were suspended in complete CellGro DC medium to 15*10 ⁶ cells/ml and diluted to 4*10 ⁶ cells/ml (Table 5).

Table 5:

* a stock solution of 166.67|j.M/each peptide (fsp2, fsp8 and fsp9) was added to the wells, giving a final concentration of =10|j.M/each peptide

On day 1, 1 ml of PBMC suspension (4x10 ⁶ cells/ml) from each donor was transferred to wells of 24-well plates (4*10 ⁶ cells per well) and 60pl of the peptide cocktail (fsp2+fsp8+fsp9) stock solution (166.67|jM/each peptide) was added to each well. The plates were incubated in a cell incubator for 14 days. IL-2 and IL-7 was added on day 3 (0.50ml DC medium containing 60 U/ml IL-2 and 15 ng/ml IL-7). The cells were inspected daily and DC medium with cytokines (IL- 2, IL7) was refreshed according to in house laboratory routines.

The in vitro stimulation of bulk cultures was repeated a further two times (i.e. a total of three stimulations) using PBMCs harvested after the preceding round of in vitro stimulation. Peptide specific T-cell proliferation was tested on day 14, after each round of stimulation, such that T- cell proliferation was tested on days 14, 28 and 42 after the first round of stimulation. iv) Three-day T-cell proliferation assay

The cells from the bulk cultures were harvested (5 minutes at 300xg centrifugation) and resuspended in DC medium (5ml). An aliquot of the 5ml resuspension was diluted 5 times and the T-cells counted in order to calculate the volume required to provide 5x10 ⁴ cells per well for the proliferation assay. T-cells from each donor were transferred (triplicates) to wells of 96-well plates (5x10 ⁴ cells per well) together with autologous, irradiated (30 Gy for 8 minutes) PBMCs (5x10 ⁴ cells per well) and test peptide(s) (final concentration 10 .M/each peptide). Negative controls were wells without test peptide(s) and positive controls were wells with SEC-3 (0.1 .g/ml) without test peptide(s). The cells (plates) were incubated for 48 hours (37°C I 5% CO2). After 48 hours, 20 pL of 3H-Thymidine (3.7 x 104 Bq) was added to the cells and incubation was continued for 17 hours. The cells were harvested (Unifilters using the Filtermate 196 Harvester) and dried on the filters for approx. 4.5 hours at 45°C. The cells were counted (CPM) by using the standard in-house laboratory protocol (TopCount Packard microplate scintillation beta counter and run programme). v) Peptide-specific T-cell proliferation

One stimulation:

Peptide-specific T-cell proliferation was measured after 14 days of stimulation of PBMC bulk cultures with a peptide cocktail containing fsp2 (SEQ ID NO: 10), fsp8 (SEQ ID NO: 19) and fsp9 (SEQ ID NO: 23) (10 .M each peptide). Proliferation induced by each of the single peptides and the peptide cocktail was tested at a concentration of 10 .M (each peptide).

Two stimulations:

Peptide-specific T-cell proliferation was measured after 14 days of re-stimulation of PBMC with a peptide cocktail containing fsp2, fsp8 and fsp9 (10 .M each peptide). T-cell proliferation induced by each of the single peptides and the peptide cocktail was tested. The single peptides were tested at a concentration of 10 .M. The peptide cocktail was tested using two different amounts of each peptide in the cocktail, namely, a peptide cocktail containing 10 .M each peptide and a peptide cocktail containing 3.33 .M each peptide.

Three stimulations:

Peptide-specific T-cell proliferation was measured after 14 days of a further re-stimulation of PBMC with a peptide cocktail containing fsp2, fsp8 and fsp9 (10 .M each peptide). T-cell proliferation induced by each of the single peptides and the peptide cocktail was tested. The single peptides were tested at a concentration of 10 .M. The peptide cocktail was tested using two different amounts of each peptide in the cocktail, namely, a peptide cocktail containing 10 .M each peptide and a peptide cocktail containing 3.33 .M each peptide.

The results of the peptide-specific T-cell proliferation assays are shown in Figures 5-9 . In particular, an increase in the SI value compared to the control shows that the peptide cocktail or specific peptide is capable of inducing a T-cell response, while a Sl> 2 is a clear signal of immunogenicity. Figure 5 shoes that after two rounds of stimulation with the peptide cocktail, T- cells were induced against the peptide cocktail in three out of four donors. Figure 6 shows that the T-cell response to the peptide cocktail after three rounds of stimulation was stronger than after 2 rounds of stimulation. Figures 7-9 show the T-cell response to each of the peptide cocktail, fsp2, fsp8 and fsp9, in three donors, and shows that all of these peptides and peptide mixtures are able to induce a T-cell response. More particularly, fsp2 has a SI greater than 2 in all three donors, fsp8 and fsp9 each has a SI greater than 2 in two out of three donors, and the peptide cocktail has a SI greater than 2 in all three donors. This indicates that each of the peptides is immunogenic, even when administered as a peptide cocktail. Furthermore, as each of fsp2, fsp8 and fsp9 is longer than HLA class-l epitopes (9-mers) and HLA class-ll epitopes (15-mers), and were designed to include more than one epitope, the peptides encompass fragments which are expected to be immunogenic.

Example 4

Using a similar procedure to that used in Examples 1 and 3 above, PMBCs from four healthy donors were stimulated in vitro with a peptide mixture containing equimolar amounts (10uM) of fsp17 (SEQ ID NO: 17), fsp15 (SEQ ID NO: 20) and fsp16 (SEQ ID NO: 24). These peptides have the non-chiral amino acid glycine at their C-terminal, which can serve as a linker for conjugation of the peptides to other molecules. It is expected that this C-terminal glycine will not create any new T-cell epitopes which will change the specificity of the induced T-cells. After one round (14 days) of in vitro stimulation, T-cells were harvested and tested for recognition of the peptide mixture or individual peptides, using a concentration of 10pM of each peptide. T-cell proliferation was measured as counts per minute (CPM) after uptake of ³ H- thymidine in a standard T cell proliferation assay.

The proliferation test results showed that T-cells are induced by fsp15 (SEQ ID NO: 20; Figure 10).

The PMBCs from the four healthy donors underwent a second round of in vitro stimulation, and T-cells were again harvested and tested for proliferation against the peptide mixture and the individual peptides. The results show that T-cells were induced by the peptide mixture (fsp17 (SEQ ID NO: 17), fsp15 (SEQ ID NO: 20) and fsp16 (SEQ ID NO: 24), and by fsp15 (SEQ ID NO: 20) and fsp17 (SEQ ID NO: 17), individually (Figure 11).

Example 5 - fsp18

Clusters (nested epitopes) of potential HLA class II T-cell epitopes (15-mers) of TGFPR2 were identified using the online algorithm SYFPEITHI. A predicted nested epitope peptide was defined, and potential HLA class I epitopes (9-mers) were predicted using SYFPEITHI and a SYFPEITHI cut off score of > 20. All HLA class I and HLA class-ll alleles provided for by SYFPEITHI were included in the searches. Candidate peptide fsp8 was designed based on an overall consideration of:

• Total HLA-coverage with main focus on H LA-class II

• Prevalence of the various HLA alleles in the general population

• A representative peptide of each protein for in vitro testing was defined

• Chemical considerations: try to avoid multiple cysteine residues, potential issues for synthesis, solubility, and stability of the potential candidate peptides

The predicted HLA class II epitopes, predicted nested epitope peptide and HLA class I epitopes, and candidate fsp9 peptide are shown in Table 6 below. In particular, Table 6 shows the epitope prediction score for each predicted HLA class II epitope in parentheses in column 3 thereof.

Surprisingly, the SYFPEITHI algorithm predictions showed that the HLA class II epitope of SEQ ID NO: 35 has particularly good SYFPEITHI prediction scores (HLA-DRB1*1101: score 28), HLA-DRB1*1501 : score 24). In particular, SEQ ID NO: 35 had the two highest prediction scores across all predicted HLA class II epitopes, and was the only predicted epitope to have a prediction score of 24 or above, as shown in Table 6. Thus, SEQ ID NO: 35 is expected to be the dominant immunogenic epitope that can be processed from the TAFip target sequence, and fsp18 was therefore designed to encompass the epitope of SEQ ID NO: 35.

able 6:

Example 6

A peptide referred to as fsp18 and having the amino acid sequence of SEQ ID NO: 21 was synthesised and purified using the method shown in Figure 15. In more detail, the peptide was prepared by solid phase peptide synthesis (SPPS) by using FMOC chemistry. The crude peptide was analysed by LIPLC, and showed a purity of around 44% (Figure 16). The peptide was dissolved and purified via preparative RP-HPLC, and isolated via intermediate lyophilisation. The purified peptide was analysed by HPLC and showed a purity of around 93.2% (Figure 17). An fsp18 acetate salt was then produced using ion exchange (Amberlite I Exresin) and submitted to final isolation via lyophilisation. The resulting fsp18 acetate salt had a purity of around 90.3% and Peak Purity analysis showed no impurities >0.5% below the main peak (Figure 18).

Example 7

The objective of this toxicity study, conducted according to Good Laboratory Practices (GLP), was to assess the toxicity and the tolerability of the mixture of fsp2 (SEQ ID NO: 10) lyophilizate, fsp8 (SEQ ID NO: 19) acetate salt and fsp18 (SEQ ID NO: 21) acetate salt (this mixture is referred to herein as “peptide mixture”) in combination with the adjuvant Molgramostim, Recombinant Human Granulocyte Macrophage Colony Stimulating Factor (GM- CSF) in the New Zealand rabbit following 4 intradermal administrations, and to assess the onset and the reversibility up to 9 days after the first administration.

Peptide mixture and its adjuvant was given to rabbits (3/sex) at 0.49 mg/dose (0.06|jmol each peptide) (as parent) and 0.03 mg/dose, respectively, 15 minutes apart in four different administrations (Days 1 , 3, 5 and 8) by intradermal injections. Each injection site was used only once in order to assess the onset and the reversibility of any effect between 24 hours and 9 days from the administration.

One additional group of 3/sex received fsp8 (SEQ ID NO: 19) acetate salt (“reference item”) and its adjuvant at the doses of 0.17 mg/dose (0.06|jmol peptide), and 0.03 mg/dose, respectively, with the same dosing scheme and a last group of 3/sex received the vehicle (sterile water for injection) alone twice, 15 minutes apart, and acted as controls.

Dose volumes administered were 0.10 mL/dose/site. The following endpoints/parameters were evaluated: body weight, clinical observations, injection site observations, haematology, clinical chemistry, organ weights, gross and histopathology.

One male given the reference item and its adjuvant died during the bleeding procedures on Day 9. The premature demise was considered not related to the reference item administration.

Local effects at injection sites:

• Slight reddening in all groups, including vehicle, in all injection sites, with a higher incidence in animals given test item/adjuvant. Slight fibrotic induration in animals treated with test item/adjuvant and reference item/adjuvant, with a higher incidence in animals given the test item/adjuvant. Sporadic or single occurrence of slight swelling, slight discoloration and slight oedema in animals given test item/adjuvant and reference item/adjuvant.

Histopathology findings at injection sites, considering major effect at 24 hours and after 4 days from the administration of test item/adjuvant and reference item/adjuvant, without evidence of differences in severity:

• Minimal to moderate, mixed cell inflammatory cell infiltration, accounting for the macroscopic red, diffuse, discolouration in the subcutis and/or thickening of the subcutis. A single instance of granuloma (mild) in the subcutis, in a female treated with test item/adjuvant in the injection site 4.

Noteworthy test item-related systemic findings were observed in animals given peptide mixture and its adjuvant GM-CSF and these included: changes in kidney, liver, spleen and thymus weights and stress-related macroscopic focal red area in the mucosa of the stomach in one female. Reference item-related systemic findings were observed in animals given fsp8 and its adjuvant GM-CSF, including changes in liver, spleen, ovary and thymus weights.

In conclusion, the peptide mixture and its adjuvant GM-CSF when administered to New Zealand rabbits at doses of 0.49 mg/dose and 0.03 mg/dose, respectively, by four single intradermal administrations, was tolerated since the treatment did not cause local nor systemic adverse effects. No relevant differences were recorded between animals received the peptide mixture/adjuvant or fsp8 acetate salt/adjuvant. Sequences

Table 7