Patent Application
20220233660
The instant application contains a Sequence Listing which has been filed electronically in ASCII format and is hereby incorporated by reference in its entirety. Said ASCII copy, created Apr. 20, 2021, is named TBL_005_SL.txt and is 7,856 bytes in size.
Provided herein are methods for determining the risk that a subject will develop a cancer based on their HLA class I genotype. Further provided herein are methods of treating cancer, particularly prophylactic treatment of subjects that have determined to have an elevated risk of developing a cancer.
Screening, where possible, and early diagnosis are critically important to prevent metastatic disease and improve prognosis for many cancers.
Heritable mutations can increase the risk of developing cancers, but known genetic factors do not fully account for the genetic contribution to cancer development risk. For example, mutations in BRCA1, BRCA2 have been identified in 5% of breast cancer cases in the general population but close to 50% of these cases developed breast cancer. Over the last decade, efforts to explain the missing heritability of developing cancer have focused on discovery of high-risk genes and identification of common genetic variants.
There remains, however, a need in the art to better identify individuals who are at elevated genetic risk of developing a cancer.
Provided herein are methods relating to a subject's human leukocyte antigen (HLA) class I genotype as a predictor for cancer development.
In antigen presenting cells (APC) protein antigens, including tumour associated antigens (TAA), are processed into peptides. These peptides bind to HLA molecules and are presented on the cell surface as peptide-HLA complexes to T cells. Different individuals express different HLA molecules, and different HLA molecules present different peptides. A TAA epitope that binds to a single HLA class I allele expressed in a subject is essential, but not sufficient to induce tumor specific T cell responses. Instead tumour specific T cell responses are optimally activated when an epitope of the TAA is recognised and presented by the HLA molecules encoded by at least three HLA class I genes (referred to herein as a HLA triplet or “HLAT”) of an individual (PCT/EP2018/055231, PCT/EP2018/055232, PCT/EP2018/055230, EP 3370065 and EP 3369431).
The inventors have developed a binary classifier that is able to separate subjects having cancer from a background population. Using this classifier, the inventors were able to demonstrate a clear association between HLA genotype and cancer risk. These findings confirm the central role of tumor specific T cell responses in the control of tumor growth and mean that HLA genotype analysis may be used to improve diagnostic tests for the early identification of subjects at a high risk of developing cancer.
Accordingly, in a first aspect the disclosure provides a method for determining the risk that a human subject will develop a cancer, the method comprising quantifying the HLA triplets (HLAT) of the subject that are capable of binding to T cell epitopes in the amino acid sequence of tumor associated antigens (TAAs), wherein each HLA of a HLAT is capable of binding to the same T cell epitope, and determining the risk that the subject will develop a cancer, wherein, with respect to a TAA, a lower number of HLATs capable of binding to T cell epitopes of the TAA corresponds to a higher risk that the subject will develop cancer.
The findings described herein also suggest that the risk of cancer can be reduced by using vaccines that are personalised to effectively activate a subject's immune system to kill tumor cells.
Accordingly, in a further aspect the disclosure provides a method of treating cancer in a subject, wherein the subject has been determined to have an elevated risk of developing cancer using the method above, and wherein the method of treatment comprises administering to the subject one or more peptides or one of more polynucleic acids or vectors that encode one or more peptides, that comprise an amino acid sequence that (i) is a fragment of a TAA; and (ii) comprises a T cell epitope capable of binding to HLAT of the subject.
In further aspects, the disclosure provides
In a further aspect the disclosure provides a system for determining the risk that a human subject will develop a cancer, the system comprising:
The methods and compositions of the present disclosure will now be described in more detail, by way of example and not limitation, and by reference to the accompanying drawings. Many equivalent modifications and variations will be apparent, to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the disclosure set forth are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the scope of the disclosure. All documents cited herein, whether supra or infra, are expressly incorporated by reference in their entirety.
The present disclosure includes the combination of the aspects and preferred features described except where such a combination is clearly impermissible or is stated to be expressly avoided. As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to “a peptide” includes two or more such peptides.
Section headings are used herein for convenience only and are not to be construed as limiting in any way.
ROC curve of HLA restricted PEPI biomarkers.
ROC curve of ≥1 PEPI3+ Test for the determination of the diagnostic accuracy. AUC=0.73 classifies a fair diagnostic value for the PEPI biomarker.
The average total HLAT Score of 48 TSAs in the different ethnic populations. Ethnic groups in far East-Asia and in the Pacific region clearly have higher HLAT numbers than the rest of the word. Ethnic groups that can be associated to countries are highlighted with black. The encoding on they axis: 1: Irish, 2: North America (Eu), 3: Czech, 4: Finn, 5: Georgian, 6: Mexican, 7: Ugandan, 8: North America (Hi), 9: New Delhi, 10: Kurdish, 11: Bulgarian, 12: Brazilian (Af, Eu), 13: Arab Druze, 14: North America (Af), 15: Tamil, 16: Amerindian, 17: Zambian, 18: Kenyan, 19: Tuva, 20: Guarani-Nandewa, 21: Kenyan Lowlander, 22: Shona, 23: Guarani-Kaiowa, 24: Zulu, 25: Doggon, 26: Saisiat, 27: Israeli Jews, 28: Canoncito, 29: North America (As), 30: Korean, 31: Groote Eylandt, 32: Toroko, 33: Siraya, 34: Cape York, 35: Okinawan, 36: Bari, 37: Kenyan Highlander, 38: Hakka, 39: Atayal, 40: Chinese, 41: Filipino, 42: Minnan, 43: Yupik, 44: Kimberley, 45: Javanese Indonesian, 46: Ivatan, 47: Thai, 48: Malay, 49: Tsou, 50: Ami, 51: Bunun, 52: Yuendumu, 53: Pazeh, 54: Thao, 55: American Samoa, 56: Rukai, 57: Paiwan, 58: Puyuma, 59: Yami
The incidence rate in countries with low HLAT Score (s<75) and with high HLAT Score (s>75). The averages are indicated with a horizontal black bar. Standard errors are indicated with vertical bars. The difference between the incidence rates are very significant (p<0.0001).
ROC curve of the immunological predictor (HLAT Score) classifying melanoma patients compared to the general populations. AUC=0.645; the solid black line is the ROC curve, the x=y line is indicated with dotted grey for sake of comparison.
The relative immunological risk of developing melanoma in five, equally large subpopulations. The HLAT Score ranges defining the subpopulations are presented on the horizontal axis. The black bars indicate the 95% confidence intervals. The difference between the first and last subgroup is significant (p=0.001).
The relative immunological risk of developing a cancer in five, equally large subpopulations. The HLAT Score ranges defining the subpopulations are presented on the horizontal axis. The black bars indicate the 95% confidence intervals. A. non-small cell lung cancer; B. renal cell carcinoma; C. colorectal cancer.
The relative risk (RR) of developing melanoma in five equal-size subgroups. The HLA-score (s) ranges defining the subgroups are shown on the x-axis. The black bars indicate the 95% confidence intervals. The difference between the first and last subgroups is significant (p<0.05).
Positive correlation between the number of antigens (n=7) resulting in vaccine-specific T cell responses (in 10 patients) and HLAT Score calculated for the panel of 48 TSAs.
The mean HLA-score in 59 different countries and ethnic populations. Ethnic groups that can be associated with countries as the country's dominant ethnicity are highlighted in black. The ethnicities encoded on the y axis: 1, Irish; 2, North America (Eu); 3, Czech; 4, Finnish; 5, Brazilian (Af, Eu); 6, Georgian; 7, Arab Druze; 8, Guarani-Kaiowa; 9, Ugandan; 10, North America (Hi); 11, New Delhi; 12, Bulgarian; 13, North America (Af); 14, Guarani-Nandewa; 15, Kurdish; 16, Israeli Jews; 17, Mexican; 18, Tamil; 19, Kenyan; 20, Kenyan Lowlander; 21, Zambian; 22, Doggon; 23, Amerindian; 24, Shona; 25, Kenyan Highlander; 26, Zulu; 27, Canoncito; 28, Tuva; 29, Saisiat; 30, Javanese Indonesian; 31, Filipino; 32, North America (As); 33, Cape York; 34, Malay; 35, Korean; 36, Thai; 37, Hakka; 38, Okinawan; 39, Chinese; 40, Groote Eylandt; 41, Minnan; 42, Ivatan; 43, Bari; 44, Kimberley (Australia); 45, Toroko; 46, Yuendumu; 47, Atayal; 48, Siraya; 49, American Samoa; 50, Yupik; 51, Pazeh; 52, Bunun; 53, Yami; 54, Tsou; 55, Ami; 56, Thao; 57, Rukai; 58, Paiwan; 59, Puyuma. Here Eu denotes European, non-Hispanic, Hs denotes Hispanic, Af means African and As means Asian.
Correlation between the melanoma incidence rate and mean HLA-scores in ethnic populations. The correlation is significant (p<0.001, transformed t score is 4.25, df=18). ASRW: age-standardized rate by world standard population.
Single HLA allele or non-complete HLA genotype has a limitation in genotype-based separation of UNPC population from non-UNPC population. A*02:01/B*18:01 AUC=0.556 (not significant).
OBERTO trial design (NCT03391232)
Antigen expression in CRC cohort of OBERTO trial (n=10). A: Expression frequencies of PolyPEPI1018 source antigens determined based on 2391 biopsies. B: PolyPEPI1018 vaccine design specified as 3 out of 7 TSAs are expressed in CRC tumors with above 95% probability. C: In average, 4 out of the 10 patients had pre-existing immune responses against each target antigens, referring to the real expression of the TSAs in the tumors of the patients. D: 7 out of the 10 patients had pre-existing immune responses against minimum of 1 TSA, in average against 3 different TSAs.
Immunogenicity of PolyPEPI1018 in CRC patients confirms proper target antigen and target peptide selection. Upper part: target peptide selection and peptide design of PolyPEPI1018 vaccine composition. Two 15mers from CRC specific CTA (TSA) selected to contain 9mer PEPI3+ predominant in representative Model population. Table: PolyPEPI1018 vaccine has been retrospectively tested during a preclinical study in a CRC cohort and was proven to be immunogenic in all tested individuals for at least one antigen by generating PEPI3+s. Clinical immune responses were measured specific for at least one antigen in 90% of patients, and multi-antigen immune responses were also found in 90% of patients against at least 2, and in 80% of patients against at least 3 antigens as tested with IFNy fluorospot assay specifically measured for the vaccine-comprising peptides.
Clinical response for PolyPEPI1018 treatment. A: Swimmer plot of clinical responses of OBERTO trial (NCT03391232). B: Association progression free survival (PFS) and AGP count. C: Association tumour volume and AGP count.
Probability of vaccine antigen expression in the Patient-A's tumor cells. There is over 95% probability that 5 out of the 13 target antigens in the vaccine regimen is expressed in the patient's tumor. Consequently, the 13 peptide vaccines together can induce immune responses against at least 5 ovarian cancer antigens with 95% probability (AGP95). It has 84% probability that each peptide will induce immune responses in the Patient-A. AGP50 is the mean (expected value)=7.9 (it is a measure of the effectiveness of the vaccine in attacking the tumor of Patient-A).
Treatment schedule of Patient-A.
T cell responses of patient-A. A. Left: Vaccine peptide-specific T cell responses (20-mers). right: CD8+ cytotoxic T cell responses (9-mers). Predicted T cell responses are confirmed by bioassay.
MRI findings of Patient-A treated with personalised (PIT) vaccine. This late stage, heavily pretreated ovarian cancer patient had an unexpected objective response after the PIT vaccine treatment. These MRI findings suggest that PIT vaccine in combination with chemotherapy significantly reduced her tumor burden.
Probability of vaccine antigen expression in the Patient-B's tumor cells and treatment schedule of Patent-B. A: There is over 95% probability that 4 out of the 13 target antigens in the vaccine is expressed in the patient's tumor. B: Consequently, the 12 peptide vaccines together can induce immune responses against at least 4 breast cancer antigens with 95% probability (AGP95). It has 84% probability that each peptide will induce immune responses in the Patient-B. AGP50=6.45; it is a measure of the effectiveness of the vaccine in attacking the tumor of Patient-B. C: Treatment schedule of Patient-B.
T cell responses of Patient-A. Left: Vaccine peptide-specific T cell responses (20-mers) of P. Right: Kinetic of vaccine-specific CD8+ cytotoxic T cell responses (9-mers). Predicted T cell responses are confirmed by bioassay.
Treatment schedule of Patient-C.
T cell responses of Patient-C. A: Vaccine peptide-specific T cell responses (20-mers). B: Vaccine peptide-specific CD8+ T cell responses (9-mers). C-D: Kinetics of vaccine-specific CD4+ T cells and CD8+ cytotoxic T cell responses (9-mers), respectively. Long lasting immune responses both CD4 and CD 8 T cell specific are present after 14 months.
Treatment schedule of Patient-D.
Immune responses of Patient-D for PIT treatment. A: CD4+ specific T cell responses (20mer) and B: CD8+ T cell specific T cell responses (9mer). 0.5-4 months refer to the timespan following the last vaccination until PBMC sample collection.
SEQ ID Nos: 1-13 set forth sequences of personalized vaccine of Patient-A and are described in Table 23.
SEQ ID Nos: 14-25 set forth sequences of personalized vaccine of Patient-B and are described in Table 25.
SEQ ID No: 26 sets forth the 30 amino acid CRC P3 peptide,
HLAs are encoded by the most polymorphic genes of the human genome. Each person has a maternal and a paternal allele for the three HLA class I molecules (HLA-A*, HLA-B*, HLA-C*) and four HLA class II molecules (HLA-DP*, HLA-DQ*, HLA-DRB1*, HLA-DRB3*/4*/5*). Practically, each person expresses a different combination of 6 HLA class I and 8 HLA class II molecules that present different epitopes from the same protein antigen.
The nomenclature used to designate the amino acid sequence of the HLA molecule is as follows: gene name*allele:protein number, which, for instance, can look like: HLA-A*02:25. In this example, “02” refers to the allele. In most instances, alleles are defined by serotypes—meaning that the proteins of a given allele will not react with each other in serological assays. Protein numbers (“25” in the example above) are assigned consecutively as the protein is discovered. A new protein number is assigned for any protein with a different amino acid sequence determining the binding specificity to non-self antigenic peptides (e.g. even a one amino acid change in sequence is considered a different protein number). Further information on the nucleic acid sequence of a given locus may be appended to the HLA nomenclature, but such information is not required for the methods described herein.
The HLA class I genotype or HLA class II genotype of an individual may refer to the actual amino acid sequence of each class I or class II HLA of an individual, or may refer to the nomenclature, as described above, that designates, minimally, the allele and protein number of each HLA gene. In some embodiments, the HLA genotype of an individual is obtained or determined by assaying a biological sample from the individual. The biological sample typically contains subject DNA. The biological sample may be, for example, a blood, serum, plasma, saliva, urine, expiration, cell or tissue sample. In some embodiments the biological sample is a saliva sample. In some embodiments the biological sample is a buccal swab sample. An HLA genotype may be obtained or determined using any suitable method. For example, the sequence may be determined via sequencing the HLA gene loci using methods and protocols known in the art. In some embodiments, the HLA genotype is determined using sequence specific primer (SSP) technologies. In some embodiments, the HLA genotype is determined using sequence specific oligonucleotide (SSO) technologies. In some embodiments, the HLA genotype is determined using sequence based typing (SBT) technologies. In some embodiments, the HLA genotype is determined using next generation sequencing. Alternatively, the HLA set of an individual may be stored in a database and accessed using methods known in the art.
A given HLA of a subject will only present to T cells a limited number of different peptides produced by the processing of protein antigens in an APC. As used herein, “display” or “present”, when used in relation to HLA, references the binding between a peptide (epitope) and an HLA. In this regard, to “display” or “present” a peptide is synonymous with “binding” a peptide.
As used herein, the term “epitope” or “T cell epitope” refers to a sequence of contiguous amino acids contained within a protein antigen that possesses a binding affinity for (is capable of binding to) one or more HLAs. An epitope is HLA- and antigen-specific (HLA-epitope pairs, predicted with known methods), but not subject specific.
The term “personal epitope”, or “PEPI” as used herein distinguishes a subject-specific epitope from an HLA specific epitope. A “PEPI” is a fragment of a polypeptide consisting of a sequence of contiguous amino acids of the polypeptide that is a T cell epitope capable of binding to one or more HLA class I molecules of a specific human subject. In other words a “PEPI” is a T cell epitope that is recognised by the HLA class I set of a specific individual. In contrast to an “epitope”, PEPIs are specific to an individual because different individuals have different HLA molecules which each bind to different T cell epitopes. In appropriate cases a “PEPI” may also refer to a fragment of a polypeptide consisting of a sequence of contiguous amino acids of the polypeptide that is a T cell epitope capable of binding to one or more HLA class II molecules of a specific human subject.
“PEPI1” as used herein refers to a peptide, or a fragment of a polypeptide, that can bind to one HLA class I molecule (or, in specific contexts, HLA class II molecule) of an individual. “PEPI1+” refers to a peptide, or a fragment of a polypeptide, that can bind to one or more HLA class I molecule of an individual.
“PEPI2” refers to a peptide, or a fragment of a polypeptide, that can bind to two HLA class I (or II) molecules of an individual. “PEPI2+” refers to a peptide, or a fragment of a polypeptide, that can bind to two or more HLA class I (or II) molecules of an individual, i.e. a fragment identified according to a method disclosed herein.
“PEPI3” refers to a peptide, or a fragment of a polypeptide, that can bind to three HLA class I (or II) molecules of an individual. “PEPI3+” refers to a peptide, or a fragment of a polypeptide, that can bind to three or more HLA class I (or II) molecules of an individual.
“PEPI4” refers to a peptide, or a fragment of a polypeptide, that can bind to four HLA class I (or II) molecules of an individual. “PEPI4+” refers to a peptide, or a fragment of a polypeptide, that can bind to four or more HLA class I (or II) molecules of an individual.
“PEPI5” refers to a peptide, or a fragment of a polypeptide, that can bind to five HLA class I (or II) molecules of an individual. “PEPI5+” refers to a peptide, or a fragment of a polypeptide, that can bind to five or more HLA class I (or II) molecules of an individual.
“PEPI6” refers to a peptide, or a fragment of a polypeptide, that can bind to all six HLA class I (or six HLA class II) molecules of an individual.
Generally speaking, epitopes presented by HLA class I molecules are about nine amino acids long. For the purposes of this disclosure, however, an epitope may be more or less than nine amino acids long, as long as the epitope is capable of binding HLA. For example, an epitope that is capable of being presented by (binding to) one or more HLA class I molecules may be between 7, or 8 or 9 and 9 or 10 or 11 amino acids long.
Using techniques known in the art, it is possible to determine the epitopes that will bind to a known HLA. Any suitable method may be used, provided that the same method is used to determine multiple HLA-epitope binding pairs that are directly compared. For example, biochemical analysis may be used. It is also possible to use lists of epitopes known to be bound by a given HLA. It is also possible to use predictive or modelling software to determine which epitopes may be bound by a given HLA. Examples are provided in Table 1. In some cases a T cell epitope is capable of binding to a given HLA if it has an IC50 or predicted IC50 of less than 5000 nM, less than 2000 nM, less than 1000 nM, or less than 500 nM.
HLA molecules regulate T cell responses. Until recently, the triggering of an immune response to individual epitopes was thought to be determined by recognition of the epitope by the product of single HLA allele, i.e. HLA-restricted epitopes. However, HLA-restricted epitopes induce T cell responses in only a fraction of individuals. Peptides that activate a T cell response in one individual are inactive in others despite HLA allele matching. Therefore, it was previously unknown how an individual's HLA molecules present the antigen-derived epitopes that positively activate T cell responses.
As described herein multiple HLA expressed by an individual need to present the same peptide in order to trigger a T cell response. Therefore the fragments of a polypeptide antigen (epitopes) that are immunogenic for a specific individual (PEPIs) are those that can bind to multiple class I (activate cytotoxic T cells) or class II (activate helper T cells) HLAs expressed by that individual. This discovery is described in PCT/EP2018/055231, PCT/EP2018/055232, PCT/EP2018/055230, EP 3370065 and EP 3369431
A “HLA triplet” or “HLAT” or “any combination HLAT” as referred to herein is any combination of three out of the six HLA class I alleles that are expressed by a human subject. An HLAT is capable of binding to a specific PEPI if all three HLA alleles of the triplet is capable of binding to the PEPI. The “HLAT number” is the total number of HLAT, made up of any combination of three HLA alleles of a subject, that are capable of binding to one or more defined polypeptides or polypeptide fragments, for example one or more antigen or a PEPI. For example, if three out of the six HLA class I alleles of a subject are able to bind to a specific PEPI then the HLAT number is one. If four out of the six HLA class I alleles of a subject are able to bind to a specific PEPI then the HLAT number is four (four combinations of any three out of four binding HLA alleles). If five out of the six HLA class I alleles of a subject are able to bind to a specific PEPI then the HLAT number is ten (ten combinations of any three out of five binding HLA alleles). If three out of the six HLA class I alleles of a subject are able to bind to a first PEPI in a polypeptide, and the same or a different combination of three out of the six HLA class I alleles of the subject are able to bind to a second PEPI in a polypeptide, then the HLAT number is two, and so on.
Some subjects may have two HLA alleles that encode the same HLA molecule (for example, two copies for HLA-A*02:25 in case of homozygosity). The HLA molecules encoded by these alleles bind all of the same T cell epitopes. For the purposes of this disclosure the HLA that are encoded by different alleles are different HLA, even if the two alleles are the same. “In other words, “binding to at least three HLA molecules of the subject” and the like could otherwise be expressed as “binding to the HLA molecules encoded by at least three HLA alleles of the subject”.
Provided herein are methods for determining the risk that a subject will develop a cancer based on their HLA class I genotype and its ability to recognise tumor-associated antigens. Because of the way that HLAT regulate T cell responses, the class I HLA genotype of a subject may represent an inherent genetic cancer risk determining factor: some subjects who inherited certain HLA genes from parents can mount broad T cell responses that effectively kill tumor cells; others with HLA genes that can recognize only few tumor antigens have poor defence against tumor cells. Based on the 6 inherited HLA alleles, the parents and the offspring have different HLA allele set. Since HLAT binding PEPIs induce T cell responses in a subject, tumor specific T cell responses of the parents are not directly inherited to the offspring.
According to the present disclosure, the presence in a TAA of an amino acid sequence that is a T cell epitope (PEPI) capable of binding to a HLAT of a subject indicates that expression of the TAA in the subject will elicit a T cell response. The greater number of HLAT that are capable of binding to epitopes of the TAA, the more effective the T cell response of the subject to expression of the TAA, and the more effective the subject will be at killing cancer cells that express the TAA. Conversely a lower number of HLAT that are capable of binding to epitopes of a TAA, the less effective the T cell response of the subject to expression of the TAA, and the less effective the subject will be at killing cancer cells that express the TAA. Tumours only arise in a subject when cancer cells that express TAAs are not detected and killed by the immune responses of the subject. Accordingly HLA genotype may represent either a genetic risk or a protective factor to the development of cancer in a subject. A higher number of HLATs capable of binding to T cell epitopes of a TAA may correspond to a lower risk that the subject will develop a tumor (cancer) that expresses the TAA. A lower number of HLATs capable of binding to T cell epitopes of a TAA may correspond to a higher risk that the subject will develop a tumor (cancer) that expresses the TAA.
In some cases the cancer is a particular type of cancer or cancer of a particular cell type of tissue. In some cases the cancer is a solid tumour. In some cases the cancer is a carcinoma, sarcoma, lymphoma, leukemia, germ cell tumor, or blastoma. The cancer may be a hormone related or dependent cancer (e.g., an estrogen or androgen related cancer) or a non-hormone related or dependent cancer. The tumor may be malignant or benign. The cancer may be metastatic or non-metastatic. The cancer may or may not be associated with a viral infection or viral oncogenes. In some cases the cancer is one or more selected from melanoma, lung cancer, renal cell cancer, colorectal cancer, bladder cancer, glioma, head and neck cancer, ovarian cancer, non-melanoma skin cancer, prostate cancer, kidney cancer, stomach cancer, liver cancer, cervix uteri cancer, oesophagus cancer, non-Hodgkin lymphoma, leukemia, pancreatic cancer, corpus uteri cancer, lip cancer, oral cavity cancer, thyroid cancer, brain cancer, nervous system cancer, gallbladder cancer, larynx cancer, pharynx cancer, myeloma, nasopharynx cancer, Hodgkin lymphoma, testis cancer, breast cancer, gastric cancer, bladder cancer, colorectal cancer, renal cell cancer, hepatocellular cancer, pediactric cancer and Kaposi sarcoma.
In other cases the method may be used to determine the risk that a subject will develop any cancer, or any combination of the cancers disclosed herein.
In other cases the method may be used to determine the risk that the subject will develop a cancer that expresses one or more specific TAAs. Suitable TAAs may be selected for use in the methods of the disclosure as further described below.
The terms “T cell response” and “immune response” are used herein interchangeably, and refer to the activation of T cells and/or the induction of one or more effector functions following recognition of one or more HLA-epitope binding pairs. In some cases an “immune response” includes an antibody response, because HLA class II molecules stimulate helper responses that are involved in inducing both long lasting CTL responses and antibody responses. Effector functions include cytotoxicity, cytokine production and proliferation.
The methods of the present disclosure may be used to determine an immunological risk of developing a cancer. Specifically the methods described herein may be used to determine a subject's ability to recognise and mount an immune response against TAAs or cancer cells that express those TAAs. Many other factors may contribute to a subject's overall risk of developing a cancer. Accordingly in some cases the methods disclosed herein may be combined with other risk determinants or incorporated into broader models for cancer risk prediction. For example a method of the present disclosure further comprises, in some embodiments, determining other cancer risk factors such as environmental factors, lifestyle factors, other genetic risk factors and any other factors that contribute to the subject's overall risk of developing cancer.
Not all the HLATs of a subject and/or that not all TAAs may play an equally important role in the immunological control of cancers. Therefore in some cases in accordance with the present disclosure a different weighting may be applied to different HLA alleles (for example using the “HLA-score” based method described in Examples 7 to 9 herein), to different HLAT, and/or to the HLAT that are capable of binding to the T cell epitopes of different TAAs (for example using the “HLAT-score” based method described in Examples 5 and 6 herein). The HLAT Score and HLA-score based methods exemplifying the invention differ in the technical computation, but in both cases a subject has a larger score if his/her predicted ability to generate immune response against TSAs is better. Both methods use a statistical learning algorithm. In case of the HLAT scores, the learning algorithm assigns weights to TSAs based on how important are the immune responses against them to fight against certain cancers. Then the final HLAT score is the weighted sums of HLA triplets that a subject can generate against the TSAs. In case of the HLA score, the learning algorithm assigns scores to individual HLA alleles based on how well HLATs can be generated against TSAs in a subject possessing that HLA allele. Then the final HLA score of a subject is the sum of the HLA alleles' weights he/she possesses.
In some cases the weighting to be applied may be determined empirically. For example in some cases the weighting applied to the HLAT that are capable of binding to the T cell epitope of a particular TAA may be determined by, based on or correlate to the capacity of each TAA to independently separate subjects having (the) cancer from subjects not having (the) cancer or from a background population of subjects including subjects having (the) cancer, using the methods described herein.
Alternatively or in addition the weighting applied to the HLAT that are capable of binding to the T cell epitope of a particular TAA may be determined by, based on, or correlate to frequency at which the TAA is expressed in a cancer or cancer type. Expression frequencies for TAAs in different cancers can be determined from published figures and scientific publications.
In some cases, the weighting applied to a particular HLAT may be determined by, based on, or correlate to the frequency with which the HLAT is present in subjects having cancer, or a subject and/or disease-matched subpopulation of subjects having cancer.
In some cases the weighting applied to the HLAT that are capable of binding to the T cell epitope of each TAA is defined as or using the following weight (w(c)):
where t(c) denotes the p-value of the one sided t-test on the HLAT score of the TAA c of the populations with and without cancer and B is the Bonferroni correction (number of TAAs). This weighting is used for the HLAT-score based method described herein.
In some cases the significance score (weighting) of an HLA allele (h) is defined as
where u(h) is the p-value of the two-sided u-test for allele h determining whether or not the number of HLATs are different in two subsets of individuals: one subset in which the individuals have HLA h, and one subset in which the individuals do not have HLA h. B is the Bonferroni correction, and sign(h) is +1 if the average number of HLATs is larger in the subpopulation having the h allele than in the subpopulation not having h, and −1 otherwise. This weighting is used for the HLA-score based method described herein.
In some cases, the initial weighting may be further optimised using any suitable method as known to those skilled in the art. In some cases the sum of these significance scores is used to determine the risk that the subject will develop cancer correlates to the risk that the subject will develop cancer.
For example, in some cases the risk that the subject will develop cancer correlates to or the risk that the subject will develop cancer is determined using the following HLAT Score (s(x)):
where C is the set of the TAAs, c is a particular TAA, w(c) is the weight of TAA c, and p(x,c) is the HLAT number of the TAA c in subject x.
The HLAT Score based method and HLA-score based method described in the Examples herein are two examples of methods in accordance with the invention. Further scoring schemes can be developed by using the individuals' HLA class I genotype data. The concrete score to be used depends on the indication and the a priori data. In some cases, the choice will be made based on the performance of the different computations on available test datasets. The performance might be evaluated by the AUC value (the area under the ROC curve) or by any other goodness of performance score known by those skilled in the art.
Cancer- or tumor-associated antigen (TAAs) are proteins expressed in cancer or tumor cells. Examples of TAAs include new antigens (neoantigens, which are expressed during tumorigenesis and altered from the analogous protein in a normal or healthy cell), products of oncogenes and tumor suppressor genes, overexpressed or aberrantly expressed cellular proteins (e.g. HER2, MUC1), antigens produced by oncogenic viruses (e.g. EBV, HPV, HCV, HBV, HTLV), cancer testis antigens (CTA, e.g. MAGE family, NY-ESO), cell-type-specific differentiation antigens (e.g. MART-1) and Tumor Specific Antigen (TSA). A TSA is an antigen produced by a particular type of tumor that does not appear on normal cells of the tissue in which the tumor developed. TSAs include shared antigens, neoantigens, and unique antigens. TAA sequences may be found experimentally, or in published scientific papers, or through publicly available databases, such as the database of the Ludwig Institute for Cancer Research (cta.lncc.br/), Cancer Immunity database (cancerimmunity.org/peptide/) and the TANTIGEN Tumor T cell antigen database (cvc.dfci.harvard.edu/tadb/). Exemplary TAAs are listed in Tables 2 and 11.
ACRBP Q8NEB7.1*
ACTL8 Q9H568.1*
ADAM2 Q99965.1*
ADAM29 Q9UKF5.1*
AKAP-3 O75969.1*
AKAP-4 Q5JQC9.1*
ANKRD45 Q5TZF3.1*
ARMC3 B4DXS3.1*
BAGE-1 Q13072.1*
BAGE-2 Q86Y30.1*
BAGE-3 Q86Y29.1*
BAGE-4 Q86Y28.1
BAGE-5 Q86Y27.1*
BRDT Q58F21.1*
C15orf60 Q7Z4M0.1*
CABYR O75952.1*
CAGE1 Q8CT20.1*
CASC5 Q8NG31.1*
CCDC110 Q8TBZ0.1*
CCDC33 Q8N5R6.1*
CCDC36 Q8IYA8.1*
CCDC62 Q6P9F0.1*
CCDC83 Q8IWF9.1*
CCNA1 P78396.1*
CDCA1 Q9BZD4.1*
CEP290 O15078.1*
CEP55 Q53EZ4.1*
COX6B2 Q6YFQ2.1*
CPXCR1 Q8N123.1*
CRISP2 P16562.1*
CT45 Q5HYN5.1*
CT45A2 Q5DJT8.1*
CT45A3 Q8NHU0.1*
CT45A4 Q8N7B7.1*
CT45A5 Q6NSH3.1*
CT45A6 P0DMU7.1*
CT46 Q86X24.1*
CT47 Q5JQC4.1*
CT47B1 P0C2P7.1*
CTAGE2 Q96RT6.1*
cTAGE5 O15320.1*
CTCFL Q8NI51.1*
CTNNA2 P26232.1*
CTSP1 A0RZH4.1*
CXorf48 Q8WUE5.1*
CXorf61 Q5H943.1*
CSAG1 Q6PB30.1*
DCAF12 Q5T6F0.1*
DKKL1 Q9UK85.1*
DMRT1 Q9Y5R6.1*
DNAJB8 Q8NHS0.1*
DPPA2 Q7Z7J5.1*
DRG1 Q9Y295.1*
EDAG Q9BXL5.1*
ELOVL4 Q9GZR5.1*
FAM133A Q8N9E0.1*
FAM46D Q8NEK8.1*
FATE1 Q969F0.1*
FBXO39 Q8N4B4.1*
FMR1NB Q8N0W7.1 *
FTHL17 Q9BXU8.1*
GAGE-1 Q13065.1
GAGE12B/C/D/E A1L429.1
GAGE12F P0CL80.1
GAGE12G P0CL81.1
GAGE12H A6NDE8.1
GAGE12I P0CL82.1
GAGE12J A6NER3.1
GAGE-2 Q6NT46.1
GAGE-3 Q13067.1
GAGE-4 Q13068.1
GAGE-5 Q13069.1
GAGE-6 Q13070.1
GAGE-7 O76087.1
GAGE-8 Q9UEU5.1
GPAT2 Q6NUI2.1*
GPATCH2 Q9NW75.1*
HAGE Q9NXZ2.1*
HOM-TES-85 Q9P127.1*
HORMAD1 Q86X24.1*
HORMAD2 Q8N7B1.1*
HSPB9 Q9BQS6.1*
IGFS11 Q5DX21.1*
IL13RA2 Q14627.1*
IMP-3 Q9NV31.1*
JARID1B Q9UGL1.1*
KIAA0100 Q14667.1*
Lage-1 O75638.1*
LDHC P07864.1*
LEMD1 Q68G75.1*
LIPI Q6XZB0.1*
LOC647107 Q8TAI5.1*
LY6K Q17RY6.1*
LYPD6B Q8NI32.1*
MAEL Q96JY0.1*
MAGE-A1 P43355.1*
MAGE-A10 P43363.1*
MAGE-A11 P43364.1*
MAGE-A12 P43365.1*
MAGE-A2 P43356.1*
MAGE-A2B Q6P448.1*
MAGE-A3 P43357.1*
MAGE-A4 P43358.1*
MAGE-A5 P43359.1*
MAGE-A6 P43360.1*
MAGE-A8 P43361.1*
MAGE-A9 P43362.1*
MAGE-B1 P43366.1*
MAGE-B2 015479.1*
MAGE-B3 O15480.1*
MAGE-B4 O15481.1*
MAGE-B5 Q9BZ81.1*
MAGE-B6 Q8N7X4.1*
MAGE-C1 O60732.1*
MAGE-C2 Q9UBF1.1*
MAGE-C3 Q8TD91.1*
MCAK Q99661.1*
MORC1 Q86VD1.1*
MPHOSPH1 Q96Q89.1*
NA88-A P0C5K6.1*
NLRP4 Q96MN2.1*
NOL4 O94818.1*
NR6A1 Q15406.1*
NXF2 Q9GZY0.1*
NXF2B Q5JRM6.1*
NY-ESO-1 P78358.1*
ODF1 Q14990.1*
ODF2 Q5BJF6.1*
ODF3 Q96PU9.1*
ODF4 Q2M2E3.1*
OIP5 O43482.1*
OTOA Q05BM7.1*
PAGE1 O75459.1*
PAGE2 Q7Z2X2.1*
PAGE2B Q5JRK9.1*
PAGE3 Q5JUK9.1*
PAGE4 O60829.1*
PAGE5 Q96GU1.1*
PASD1 Q8IV76.1*
PBK Q96KB5.1*
PEPP2 Q9HAU0.1*
PIWIL1 Q96J94.1*
PIWIL2 Q8TC59.1*
PLAC1 Q9HBJ0.1*
POYEA Q6S8J7.1*
POTEB Q6S5H4.1*
POTEC B2RU33.1*
POTED Q86YR6.1*
POYEE Q6S8J3.1*
POTEG Q6S5H5.1*
POTEH Q6S545.1*
PRAME P78395.1*
PRM1 P04553.1*
PRM2 P04554.1*
PRSS54 Q6PEW0.1*
PRSS55 Q6UWB4.1*
PTPN20A Q4JDL3.1*
RBM46 Q8TBY0.1*
RGS22 Q8NE09.1*
ROPN1A Q9HAT0.1*
RQCD1 Q92600.1*
SAGE1 Q9NXZ1.1*
SEMG1 P04279.1*
SLC06A1 Q86UG4.1*
SPA17 Q15506.1*
SPACA3 Q8IXA5.1*
SPAG1 Q07617.1*
SPAG17 Q6Q759.1*
SPAG4 Q9NPE6.1*
SPAG6 O75602.1*
SPAG8 Q99932.1*
SPAG9 O60271.1*
SPANXA1 Q9NS26.1*
SPANXB Q9NS25.1*
SPANXC Q9NY87.1*
SPANXD Q9BXN6.1*
SPANXE Q8TAD1.1*
SPANXN1 Q5VSR9.1*
SPANXN2 Q5MJ10.1*
SPANXN3 Q5MJ09.1*
SPANXN4 Q5MJ08.1*
SPANXN5 Q5MJ07.1*
SPATA19 Q7Z5L4.1*
SPEF2 Q9C093.1*
SPINLW1 O95925.1*
SPO11 Q9Y5K1.1*
SSX-1 Q16384.1*
SSX-2 Q16385.1*
SSX-3 Q99909.1*
SSX-4 O60224.1*
SSX-5 060225.1*
SSX-6 Q7RTT6.1*
SSX-7 Q7RTT5.1*
SSX-9 Q7RTT3.1*
SYCP1 Q15431.1
TAF7L Q5H9L4.1*
TAG-1 Q02246.1*
TDRD1 Q9BXT4.1*
TDRD4 Q9BXT8.1*
TDRD6 O60522.1*
TEKT5 Q96M29.1*
TEX101 Q9BY14.1*
TEX14 Q8IWB6.1*
TEX15 Q9BXT5.1*
TEX38 Q6PEX7.1*
TFDP3 Q5H9I0.1*
THEG Q9P2T0.1*
TMEFF1 Q8IYR6.1*
TMEFF2 Q9UIK5.1*
TMEM108 Q6UXF1.1*
TMPRSS12 Q86WS5.1*
TPPP2 P59282.1*
TPTE P56180.1*
TRAG-3 Q9Y5P2.1*
TSGA10 Q9BZW7.1*
TSPY1 Q01534.1*
TSPY2 A6NKD2.1*
TSPY3 Q6B019.1*
TSSK6 Q9BXA6.1*
TTK P33981.1*
TULP2 O00295.1*
XAGE-1 Q9HD64.1*
XAGE-2 Q96GT9.1*
XAGE-3 Q8WTP9.1*
XAGE-5 Q8WWM1.1*
ZNF165 P49910.1*
ZNF645 Q8N7E2.1*
In some cases the methods described herein are used to determine the risk that a subject will develop a cancer that expresses one or more specific TAAs. In other cases the method is used to determine the risk that that a subject will develop any cancer or a particular type of cancer. Different TAAs may in some cases be associated with different types of cancer, but not every cancer of a particular type will express the same combination of TAAs. Therefore in some cases the epitope-binding HLAT is quantified in multiple TAAs, in some cases at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 25, 30, 35, 40, 45 or more TAA. In general fewer TAAs may be used if the TAAs are expressed in a higher proportion of cancers or cancer patients or cancers of a selected type. More TAAs may be used if the TAAs are expressed in a lower proportion of cancers or cancer patients or cancers of a selected type. In some cases a set of TAAs may be used that together are expressed or over-expressed in a minimum proportion of cancers, cancer patients, or cancers of a selected type, for example 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98% or more. Expression frequencies for TAAs in different cancers can be determined from published figures and scientific publications.
A TAA selected for use in accordance with the present disclosure is typically one that is expressed or over-expressed in a high proportion of cancers or cancers of a particular type. In some cases one or more or each of the TAAs may be expressed or over-expressed in at least 1%, 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or the cancers, or in the cancers of a disease and/or subject-matched human population. For example the subject may be matched by ethnicity, geographical location, gender, age, disease, disease type or stage, genotype, the expression of one or more biomarkers or the like, or any combination thereof.
In some cases one or more or each of the TAAs is a tumor specific antigen (TSA) or a cancer testis antigens (CTA). CTA are not typically expressed beyond embryonic development in healthy cells. In healthy adults, CTA expression is limited to male germ cells that do not express HLAs and cannot present antigens to T cells. Therefore, CTAs are considered expressional neoantigens when expressed in cancer cells. CTA expression is (i) specific for tumor cells, (ii) more frequent in metastases than in primary tumors and (iii) conserved among metastases of the same patient (Gajewski ed. Targeted Therapeutics in Melanoma. Springer New York. 2012).
In some cases the method comprises the step of selecting and/or identifying suitable TAAs or a suitable set of TAAs for use in the method disclosed herein.
In some cases the methods described herein comprise the selection, preparation and/or administration of a treatment for a cancer in a subject. The subject may have been determined to have an elevated risk of developing the cancer using a method as described herein. A “treatment” as used herein is any action taken to prevent or delay the onset of cancer, to ameliorate one or more symptom or complication, to induce or prolong remission, to delay a relapse, recurrence or deterioration, or otherwise improve or stabilise the disease status of or cancer risk to the subject. Typically the treatment will be a prophylactic treatment intended to delay or prevent onset of cancer or any symptom or complication associated with cancer. The treatment may be immunotherapy or vaccination.
The term “treatment” as used herein may in some cases encompass recommendations concerning the behaviour, environmental exposure or lifestyle of the subject that are intended to reduce the risk that the subject will develop cancer or any symptom or complication associated with the cancer. For example, for a subject that is determined to have an elevated risk of developing melanoma the treatment may include recommending a reduction in exposure of the subject to UV radiation. This may, for example, include avoiding artificial UV sources, reducing sun exposure or avoiding sun exposure at certain times of the day, applying sunscreen that provides suitable protection, wearing protective clothing, avoiding burning, and/or taking vitamin D. In other example the treatment may include recommendations related to diet, including the use of dietary supplements (for example anti-oxidant supplements, or increased calcium intake), drug use (including reducing tobacco and/or alcohol consumption), exercise, or exposure to potential carcinogens, infectious agents and/or radiation.
In other cases the treatment may include additional or increased frequency of screenings or examinations intended to achieve early diagnosis of cancer. In other cases the treatment may include the administration of anti-inflammatory medications, such as aspirin or non-steroidal anti-inflammatory drugs, or avoiding or reducing the administration of immunosuppressive drugs. In some cases the treatment may include increased attention to the management of other conditions that are potential risk factors, such as obesity, or conditions that are associated with chronic inflammation such as ulcerative colitis and Crohn's disease.
In other cases the treatment may be any known therapeutic or prophylactic treatment for cancer, such as surgery, chemotherapy, cytotoxic or non-cytotoxic chemotherapy, radiation therapy, targeted therapy, hormone therapy, or the administration of targeted small-molecule drugs or antibodies, e.g. monoclonal antibodies or co-stimulatory antibodies and including any cancer treatment described herein.
Treatments that are intended to enhance a subject's immune response to cancer cells are likely to be particularly effective in preventing or delaying the development of cancer in a subject that is determined to have an elevated risk of cancer using a method described herein. Accordingly in some cases the treatment may be immunotherapy or checkpoint blockade therapy or checkpoint inhibitor therapy. In some cases the method comprises administering to the subject one or more peptides or one of more polynucleic acids or vectors that encode one or more peptides as described below, that comprise an amino acid sequence that is (i) a fragment of an antigen that is associated with expression in the cancer; and (ii) a T cell epitope capable of binding to HLAT of the subject.
According to the present disclosure, the ability of HLAT of a subject to recognise TAAs is predictive of the subject's risk of developing cancer. It follows that a subject's risk of developing cancer may be reduced by stimulating the subject's immune responses using peptides that correspond to the epitopes of TAAs that are recognised by HLAT of the subject.
Accordingly in some cases the disclosure relates to a method of prophylactic treatment of cancer, wherein the method comprises administering to the subject one or more peptides, or one of more polynucleic acids or vectors that encode one or more peptides, that comprise an amino acid sequence that is (i) a fragment of a TAA; and (ii) a T cell epitope capable of binding to HLAT of the subject (i.e. a PEPI3+). In some cases the subject has been determined to be at elevated risk of developing a cancer using a method described herein.
One or more suitable TAA(s) and suitable epitopes in the TAA that bind to HLAT of the subject may be selected as described herein. In some cases the method may comprise the step of identifying and/or selecting suitable TAAs, epitopes and/or peptides. Typically one or more of each TAA will be a TAA that is frequently expressed in cancer cells.
In some cases the subject is determined to be at elevated risk of developing a cancer in which cancer cells express a specific TAA. This may be the case if the TAA comprises few epitopes that are PEPI3+ for the specific subject, or the epitopes of the TAA are recognised by few HLAT of the subject. The treatment for the subject may comprise administration of a peptide comprising an amino acid sequence that (i) is a fragment of that TAA and (ii) comprises a T cell epitope capable of binding to one or more HLAT of the subject.
In other cases the subject is determined to be at elevated risk of developing one or more particular types of cancer, for example any of the types of cancer disclosed herein. The treatment for the subject may comprise administration of a peptide comprising an amino acid sequence that (i) is a fragment a TAA that is associated with expression in that cancer type and (ii) comprises a T cell epitope capable of binding to one or more HLAT of the subject.
In some cases the TAA is one that is recognised by few HLAT of the subject. Such treatment will enhance the T cell responses against the TAA. In other cases the TAA may be one that is recognised by multiple HLAT. The subject will generally already be capable of mounting a broad T cell response against such a TAA. This may in particular help to kill cancer cells that frequently co-express the target TAA with other TAAs that might be less well recognised by the HLAT of the subject.
The peptides may be engineered or non-naturally occurring. The fragment and/or the peptide may be up to 50, 45, 40, 35, 30, 25, 20, 15, 14, 13, 12, 11, 10 or 9 amino acids in length. Typically the peptide may be 15 or 20 to 30 or 35 amino acids in length. In some cases the amino acid sequence that corresponds to a fragment of a TAA is flanked at the N and/or C terminus by additional amino acids that are not part of the consecutive sequence of the TAA. In some cases the sequence is flanked by up to 41 or 35 or 30 or 25 or 20 or 15 or 10, or 9 or 8 or 7 or 6 or 5 or 4 or 3 or 2 or 1 additional amino acid at the N and/or C terminus. In other cases each peptide may either consist of a fragment of a TAA, or consist of two or more such fragments arranged end to end (arranged sequentially in the peptide end to end) or overlapping in a single peptide.
In some cases the method of treatment comprises administering to the subject one or more peptides, or one or more nucleic acids or vectors that encode one or more peptides, that comprise at least 2, or 3, or 4, or 5, or 6, or 7, or 8, or 9, or 10, or 11, or 12, or 13, or 14, or 15, or 20, or 25, or 30, or 35, or 40, or 45, or 50 or more different T cell epitopes (PEPIs) that are each (i) comprised in a fragment of a TAA and (ii) capable of binding to HLAT of the subject. In some cases two or more of the PEPIs is comprised in fragments of at least 2, or 3, or 4, or 5, or 6, or 7, or 8, or 9, or 10, or 11, or 12 or more different TAAs. In some cases one or more or each of the TAAs is a TSA and/or CTA.
In some cases one or more of the peptides fragments comprises an amino acid sequence that is a T cell epitope capable of binding to at least three, or at least four HLA class II alleles of the subject. Such a treatment may elicit both a CD8+ T cell response and a CD4+ T cell response in the subject receiving the treatment.
In some cases the method of treatment comprises administering to the subject any one or more of the peptides, or one or more nucleic acids or vectors encoding one of more of the peptides, or administering any of the pharmaceutical compositions as described in any one of PCT/EP2018/055231, PCT/EP2018/055232, PCT/EP2018/055230, EP 3370065 and EP 3369431. In some specific cases the treatment is for the prevention of breast cancer, ovarian cancer or colorectal cancer and comprises administration of a compositions described in PCT/EP2018/055230 and/or EP 3369431.
As used herein, the term “polypeptide” refers to a full-length protein, a portion of a protein, or a peptide characterized as a string of amino acids. The term “peptide” refers to a short polypeptide. The terms “fragment” or “fragment of a polypeptide” as used herein refer to a string of amino acids or an amino acid sequence typically of reduced length relative to the or a reference polypeptide and comprising, over the common portion, an amino acid sequence identical to the reference polypeptide. Such a fragment according to the disclosure may be, where appropriate, included in a larger polypeptide of which it is a constituent. In some cases the fragment may comprise the full length of the polypeptide, for example where the whole polypeptide, such as a 9 amino acid peptide, is a single T cell epitope. In some cases a peptide or a fragment of a polypeptide may be between 7, or 8, or 9, or 10, or 11, or 12, or 13, or 14, or 15 and 10, or 11, or 12, or 13, or 14, or 15, or 20, or 25, or 30, or 35, or 40, or 45, or 50 amino acids in length.
In some cases the disclosure relates to a method of treatment comprising administering to a subject one or more peptides as described herein. The one or more peptides may be administered to the subject together or sequentially. For example the treatment may comprise administration of a number of peptides over a period of, for example, up to a year. In some cases a treatment cycle may also be repeated, to boost the immune response.
In addition to the one or more peptides, a pharmaceutical composition for administration to the subject may comprise a pharmaceutically acceptable excipient, carrier, diluent, buffer, stabiliser, preservative, adjuvant or other materials well known to those skilled in the art. Such materials are preferably non-toxic and preferably do not interfere with the pharmaceutical activity of the active ingredient(s). The pharmaceutical carrier or diluent may be, for example, water containing solutions. The precise nature of the carrier or other material may depend on the route of administration, e.g. oral, intravenous, cutaneous or subcutaneous, nasal, intramuscular, intradermal, and intraperitoneal routes.
In order to increase the immunogenicity of the composition, the pharmacological compositions may comprise one or more adjuvants and/or cytokines.
Suitable adjuvants include an aluminum salt such as aluminum hydroxide or aluminum phosphate, but may also be a salt of calcium, iron or zinc, or may be an insoluble suspension of acylated tyrosine, or acylated sugars, or may be cationically or anionically derivatised saccharides, polyphosphazenes, biodegradable microspheres, monophosphoryl lipid A (MPL), lipid A derivatives (e.g. of reduced toxicity), 3-O-deacylated MPL [3D-MPL], quil A, Saponin, QS21, Freund's Incomplete Adjuvant (Difco Laboratories, Detroit, Mich.), Merck Adjuvant 65 (Merck and Company, Inc., Rahway, N.J.), AS-2 (Smith-Kline Beecham, Philadelphia, Pa.), CpG oligonucleotides, bioadhesives and mucoadhesives, microparticles, liposomes, polyoxyethylene ether formulations, polyoxyethylene ester formulations, muramyl peptides or imidazoquinolone compounds (e.g. imiquamod and its homologues). Human immunomodulators suitable for use as adjuvants in the disclosure include cytokines such as interleukins (e.g. IL-1, IL-2, IL-4, IL-5, IL-6, IL-7, IL-12, etc), macrophage colony stimulating factor (M-CSF), tumour necrosis factor (TNF), granulocyte, macrophage colony stimulating factor (GM-CSF) may also be used as adjuvants.
In some embodiments, the compositions comprise an adjuvant selected from the group consisting of Montanide ISA-51 (Seppic, Inc., Fairfield, N.J., United States of America), QS-21 (Aquila Biopharmaceuticals, Inc., Lexington, Mass., United States of America), GM-CSF, cyclophosamide, bacillus Calmette-Guerin (BCG), Corynbacterium parvum, levamisole, azimezone, isoprinisone, dinitrochlorobenezene (DNCB), keyhole limpet hemocyanins (KLH), Freunds adjuvant (complete and incomplete), mineral gels, aluminum hydroxide (Alum), lysolecithin, pluronic polyols, polyanions, peptides, oil emulsions, dinitrophenol, diphtheria toxin (DT).
Examples of suitable compositions of polypeptide fragments and methods of administration are provided in Esseku and Adeyeye (2011) and Van den Mooter G. (2006). Vaccine and immunotherapy composition preparation is generally described in Vaccine Design (“The subunit and adjuvant approach” (eds Powell M. F. & Newman M. J. (1995) Plenum Press New York). Encapsulation within liposomes, which is also envisaged, is described by Fullerton, U.S. Pat. No. 4,235,877.
The method of treatment may comprise administering to the subject a pharmaceutical composition comprising one or more peptides as described herein as active ingredients. The term “active ingredient” as used herein refers to a peptide that is intended to induce an immune response in a subject to which the pharmaceutical composition may be administered. The active ingredient peptide may in some cases be a peptide product of a vaccine or immunotherapy composition that is produced in vivo after administration to a subject. For a DNA or RNA immunotherapy composition, the peptide may be produced in vivo by the cells of a subject to whom the composition is administered. For a cell-based composition, the polypeptide may be processed and/or presented by cells of the composition, for example autologous dendritic cells or antigen presenting cells pulsed with the polypeptide or comprising an expression construct encoding the polypeptide.
In some embodiments, the compositions disclosed herein may be prepared as a nucleic acid vaccine. In some embodiments, the nucleic acid vaccine is a DNA vaccine. In some embodiments, DNA vaccines, or gene vaccines, comprise a plasmid with a promoter and appropriate transcription and translation control elements and a nucleic acid sequence encoding one or more polypeptides of the disclosure. In some embodiments, the plasmids also include sequences to enhance, for example, expression levels, intracellular targeting, or proteasomal processing. In some embodiments, DNA vaccines comprise a viral vector containing a nucleic acid sequence encoding one or more polypeptides of the disclosure. In additional aspects, the compositions disclosed herein comprise one or more nucleic acids encoding peptides determined to have immunoreactivity with a biological sample. For example, in some embodiments, the compositions comprise one or more nucleotide sequences encoding 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or more peptides comprising a fragment that is a T cell epitope capable of binding to at least three HLA class I molecules of a patient. In some embodiments the DNA or gene vaccine also encodes immunomodulatory molecules to manipulate the resulting immune responses, such as enhancing the potency of the vaccine, stimulating the immune system or reducing immunosuppression. Strategies for enhancing the immunogenicity of DNA or gene vaccines include encoding of xenogeneic versions of antigens, fusion of antigens to molecules that activate T cells or trigger associative recognition, priming with DNA vectors followed by boosting with viral vector, and utilization of immunomodulatory molecules. In some embodiments, the DNA vaccine is introduced by a needle, a gene gun, an aerosol injector, with patches, via microneedles, by abrasion, among other forms. In some forms the DNA vaccine is incorporated into liposomes or other forms of nanobodies. In some embodiments, the DNA vaccine includes a delivery system selected from the group consisting of a transfection agent; protamine; a protamine liposome; a polysaccharide particle; a cationic nanoemulsion; a cationic polymer; a cationic polymer liposome; a cationic nanoparticle; a cationic lipid and cholesterol nanoparticle; a cationic lipid, cholesterol, and PEG nanoparticle; a dendrimer nanoparticle. In some embodiments, the DNA vaccines is administered by inhalation or ingestion. In some embodiments, the DNA vaccine is introduced into the blood, the thymus, the pancreas, the skin, the muscle, a tumor, or other sites.
In some embodiments, the compositions disclosed herein are prepared as an RNA vaccine. In some embodiments, the RNA is non-replicating mRNA or virally derived, self-amplifying RNA. In some embodiments, the non-replicating mRNA encodes the peptides disclosed herein and contains 5′ and 3′ untranslated regions (UTRs). In some embodiments, the virally derived, self-amplifying RNA encodes not only the peptides disclosed herein but also the viral replication machinery that enables intracellular RNA amplification and abundant protein expression. In some embodiments, the RNA is directly introduced into the individual. In some embodiments, the RNA is chemically synthesized or transcribed in vitro. In some embodiments, the mRNA is produced from a linear DNA template using a T7, a T3, or an Sp6 phage RNA polymerase, and the resulting product contains an open reading frame that encodes the peptides disclosed herein, flanking UTRs, a 5′ cap, and a poly(A) tail. In some embodiments, various versions of 5′ caps are added during or after the transcription reaction using a vaccinia virus capping enzyme or by incorporating synthetic cap or anti-reverse cap analogues. In some embodiments, an optimal length of the poly(A) tail is added to mRNA either directly from the encoding DNA template or by using poly(A) polymerase. The RNA encodes one or more peptides comprising a fragment that is a T cell epitope capable of binding to at least three HLA class I molecules of a patient. In some embodiments, the RNA includes signals to enhance stability and translation. In some embodiments, the RNA also includes unnatural nucleotides to increase the half-life or modified nucleosides to change the immunostimulatory profile. In some embodiments, the RNAs is introduced by a needle, a gene gun, an aerosol injector, with patches, via microneedles, by abrasion, among other forms. In some forms the RNA vaccine is incorporated into liposomes or other forms of nanobodies that facilitate cellular uptake of RNA and protect it from degradation. In some embodiments, the RNA vaccine includes a delivery system selected from the group consisting of a transfection agent; protamine; a protamine liposome; a polysaccharide particle; a cationic nanoemulsion; a cationic polymer; a cationic polymer liposome; a cationic nanoparticle; a cationic lipid and cholesterol nanoparticle; a cationic lipid, cholesterol, and PEG nanoparticle; a dendrimer nanoparticle; and/or naked mRNA; naked mRNA with in vivo electroporation; protamine-complexed mRNA; mRNA associated with a positively charged oil-in-water cationic nanoemulsion; mRNA associated with a chemically modified dendrimer and complexed with polyethylene glycol (PEG)-lipid; protamine-complexed mRNA in a PEG-lipid nanoparticle; mRNA associated with a cationic polymer such as polyethylenimine (PEI); mRNA associated with a cationic polymer such as PEI and a lipid component; mRNA associated with a polysaccharide (for example, chitosan) particle or gel; mRNA in a cationic lipid nanoparticle (for example, 1,2-dioleoyloxy-3-trimethylammoniumpropane (DOTAP) or dioleoylphosphatidylethanolamine (DOPE) lipids); mRNA complexed with cationic lipids and cholesterol; or mRNA complexed with cationic lipids, cholesterol and PEG-lipid. In some embodiments, the RNA vaccine is administered by inhalation or ingestion. In some embodiments, the RNA is introduced into the blood, the thymus, the pancreas, the skin, the muscle, a tumor, or other sites, and/or by an intradermal, intramuscular, subcutaneous, intranasal, intranodal, intravenous, intrasplenic, intratumoral or other delivery route.
Polynucleotide or oligonucleotide components may be naked nucleotide sequences, or be in combination with cationic lipids, polymers or targeting systems. They may be delivered by any available technique. For example, the polynucleotide or oligonucleotide is introduced by needle injection, preferably intradermally, subcutaneously or intramuscularly. Alternatively, the polynucleotide or oligonucleotide is delivered directly across the skin using a delivery device such as particle-mediated gene delivery. The polynucleotide or oligonucleotide may be administered topically to the skin, or to mucosal surfaces for example by intranasal, oral, or intrarectal administration.
Uptake of polynucleotide or oligonucleotide constructs may be enhanced by several known transfection techniques, for example those including the use of transfection agents. Examples of these agents include cationic agents, for example, calcium phosphate and DEAE-Dextran and lipofectants, for example, lipofectam and transfectam. The dosage of the polynucleotide or oligonucleotide to be administered can be altered.
Administration is typically in a “prophylactically effective amount” or a “therapeutically effective amount” (as the case may be, although prophylaxis may be considered therapy), this being sufficient to result in a clinical response or to show clinical benefit to the individual, e.g. an effective amount to prevent or delay onset of the disease or condition, to ameliorate one or more symptoms, to induce or prolong remission, or to delay relapse or recurrence. In some cases the methods of treatment according to the disclosure may be performed for the prophylaxis of cancer recurrence or metastasis in persons with a cured primary cancer disease.
The dose may be determined according to various parameters, especially according to the substance used; the age, weight and condition of the individual to be treated; the route of administration; and the required regimen. The amount of antigen in each dose is selected as an amount which induces an immune response. A physician will be able to determine the required route of administration and dosage for any particular individual. The dose may be provided as a single dose or may be provided as multiple doses, for example taken at regular intervals, for example 2, 3 or 4 doses administered hourly. Typically peptides, polynucleotides or oligonucleotides are typically administered in the range of 1 pg to 1 mg, more typically 1 pg to 10 μg for particle mediated delivery and 1 μg to 1 mg, more typically 1-100 μg, more typically 5-50 μg for other routes. Generally, it is expected that each dose will comprise 0.01-3 mg of antigen. An optimal amount for a particular vaccine can be ascertained by studies involving observation of immune responses in subjects.
Examples of the techniques and protocols mentioned above can be found in Remington's Pharmaceutical Sciences, 20th Edition, 2000, pub. Lippincott, Williams & Wilkins.
Routes of administration include but are not limited to intranasal, oral, subcutaneous, intradermal, and intramuscular. Typically administration is subcutaneous. Subcutaneous administration may for example be by injection into the abdomen, lateral and anterior aspects of upper arm or thigh, scapular area of back, or upper ventrodorsal gluteal area.
The skilled artisan will recognize that the composition may also be administered in one, or more doses, as well as, by other routes of administration. For example, such other routes include, intracutaneously, intravenously, intravascularly, intraarterially, intraperitnoeally, intrathecally, intratracheally, intracardially, intralobally, intramedullarly, intrapulmonarily, and intravaginally. Depending on the desired duration of the treatment, the compositions according to the disclosure may be administered once or several times, also intermittently, for instance on a monthly basis for several months or years and in different dosages.
The methods of treatment according to the disclosure may be performed alone or in combination with other pharmacological compositions or treatments, for example behavioural or lifestyle changes, chemotherapy, immunotherapy and/or vaccine. The other therapeutic compositions or treatments may for example be one or more of those discussed herein, and may be administered either simultaneously or sequentially with (before or after) the composition or treatment of the disclosure.
In some cases the treatment may be administered in combination with surgery, chemotherapy, cytotoxic or non-cytotoxic chemotherapy, radiation therapy, targeted therapy, hormone therapy, or the administration of targeted small-molecule drugs or antibodies, e.g. monoclonal antibodies or co-stimulatory antibodies. It has been demonstrated that chemotherapy sensitizes tumors to be killed by tumor specific cytotoxic T cells induced by vaccination (Ramakrishnan et al. J Clin Invest. 2010; 120(4):1111-1124). Examples of chemotherapy agents include alkylating agents including nitrogen mustards such as mechlorethamine (HN2), cyclophosphamide, ifosfamide, melphalan (L-sarcolysin) and chlorambucil; anthracyclines; epothilones; nitrosoureas such as carmustine (BCNU), lomustine (CCNU), semustine (methyl-CCNU) and streptozocin (streptozotocin); triazenes such as decarbazine (DTIC; dimethyltriazenoimidazole-carboxamide; ethylenimines/methylmelamines such as hexamethylmelamine, thiotepa; alkyl sulfonates such as busulfan; Antimetabolites including folic acid analogues such as methotrexate (amethopterin); alkylating agents, antimetabolites, pyrimidine analogs such as fluorouracil (5-fluorouracil; 5-FU), floxuridine (fluorodeoxyuridine; FUdR) and cytarabine (cytosine arabinoside); purine analogues and related inhibitors such as mercaptopurine (6-mercaptopurine; 6-MP), thioguanine (6-thioguanine; TG) and pentostatin (2′-deoxycoformycin); epipodophylotoxins; enzymes such as L-asparaginase; biological response modifiers such as IFNα, IL-2, G-CSF and GM-CSF; platinum coordination complexes such as cisplatin (cis-DDP), oxaliplatin and carboplatin; anthracenediones such as mitoxantrone and anthracycline; substituted urea such as hydroxyurea; methylhydrazine derivatives including procarbazine (N-methylhydrazine, MIH) and procarbazine; adrenocortical suppressants such as mitotane (o,p′-DDD) and aminoglutethimide; taxol and analogues/derivatives; hormones/hormonal therapy and agonists/antagonists including adrenocorticosteroid antagonists such as prednisone and equivalents, dexamethasone and aminoglutethimide, progestin such as hydroxyprogesterone caproate, medroxyprogesterone acetate and megestrol acetate, estrogen such as diethylstilbestrol and ethinyl estradiol equivalents, antiestrogen such as tamoxifen, androgens including testosterone propionate and fluoxymesterone/equivalents, antiandrogens such as flutamide, gonadotropin-releasing hormone analogs and leuprolide and non-steroidal antiandrogens such as flutamide; natural products including vinca alkaloids such as vinblastine (VLB) and vincristine, epipodophyllotoxins such as etoposide and teniposide, antibiotics such as dactinomycin (actinomycin D), daunorubicin (daunomycin; rubidomycin), doxorubicin, bleomycin, plicamycin (mithramycin) and mitomycin (mitomycin C), enzymes such as L-asparaginase, and biological response modifiers such as interferon alphenomes.
The disclosure provides a system. The system may comprise a storage module configured to store data comprising the HLA class I genotype of a subject and the amino acid sequences of TAAs. The system may comprise a computation module configured to quantify the HLAT of the subject that are capable of binding to T cell epitopes in the amino acid sequence of the TAAs, wherein each HLA of a HLAT is capable of binding to the same T cell epitope. The system may comprise a module for receiving at least one sample from at least one subject. The system may comprise a HLA genotyping module for determining the class I and/or class II HLA genotype of a subject. The storage module may be configured to store the data output from the genotyping module. The HLA genotyping module may receive a biological sample obtained from the subject and determines the subject's class I and/or class II HLA genotype. The sample typically contains subject DNA. The sample may be, for example, a blood, serum, plasma, saliva, urine, expiration, cell or tissue sample. The system may further comprise an output module configured to display an indication of the risk that the subject will develop a cancer and/or a recommended treatment for the subject as described herein.
Predicted binding between particular HLA and epitopes (9 mer peptides) was based on the Immune Epitope Database tool for epitope prediction (iedb.org).
The HLA I-epitope binding prediction process was validated by comparison with HLA class I-epitope pairs determined by laboratory experiments. A dataset was compiled of HLA I-epitope pairs reported in peer reviewed publications or public immunological databases.
The rate of agreement with the experimentally determined dataset was determined (Table 3). The binding HLA I-epitope pairs of the dataset were correctly predicted with a 93% probability. Coincidentally the non-binding HLA I-epitope pairs were also correctly predicted with a 93% probability.
The accuracy of the prediction of multiple HLA binding epitopes was also determined (Table 4). Based on the analytical specificity and sensitivity using the 93% probability for both true positive and true negative prediction and 7% (=100%-93%) probability for false positive and false negative prediction, the probability of the existence of a multiple HLA binding epitope in a person can be calculated. The probability of multiple HLA binding to an epitope shows the relationship between the number of HLAs binding an epitope and the expected minimum number of real binding. Per PEPI definition three is the expected minimum number of HLA to bind an epitope (bold).
The validated HLA-epitope binding prediction process was used to determine all HLA-epitope binding pairs described in the Examples below.
This study investigates whether the presentation of one or more epitopes of a polypeptide antigen by one or more HLA class I molecule of an individual is predictive for a CTL response.
The study was carried out by retrospective analysis of six clinical trials, conducted on 71 cancer patients and 9 HIV-infected patients (Table 5). Patients from these studies were treated with an HPV vaccine, three different NY-ESO-1 specific cancer vaccines, one HIV-1 vaccine and a CTLA-4 specific monoclonal antibody (Ipilimumab) that was shown to reactivate CTLs against NY-ESO-1 antigen in melanoma patients. All of these clinical trials measured antigen specific CD8+ CTL responses (immunogenicity) in the study subjects after vaccination. In some cases, correlation between CTL responses and clinical responses were reported.
No patient was excluded from the retrospective study for any reason other than data availability. The 157 patient datasets (Table 5) were randomized with a standard random number generator to create two independent cohorts for training and evaluation studies. In some cases, the cohorts contained multiple datasets from the same patient, resulting in a training cohort of 76 datasets from 48 patients and a test/validation cohort of 81 datasets from 51 patients.
The reported CD8+ T cell responses of the training dataset were compared with the HLA class I restriction profile of epitopes (9 mers) of the vaccine antigens. The antigen sequences and the HLA class I genotype of each patient were obtained from publicly available protein sequence databases or peer reviewed publications and the HLA I-epitope binding prediction process was blinded to patients' clinical CD8+ T cell response data where CD8+ T cells are IFN-γ producing CTL specific for vaccine peptides (9 mers). The number of epitopes from each antigen predicted to bind to at least 1 (PEPI1+), or at least 2 (PEPI2+), or at least 3 (PEPI3+), or at least 4 (PEPI4+), or at least 5 (PEPI5+), or all 6 (PEPI6) HLA class I molecules of each patient was determined and the number of HLA bound were used as classifiers for the reported CTL responses. The true positive rate (sensitivity) and true negative rate (specificity) were determined from the training dataset for each classifier (number of HLA bound) separately.
ROC analysis was performed for each classifier. In a ROC curve, the true positive rate (Sensitivity) was plotted in function of the false positive rate (1-Specificity) for different cut-off points (
The analysis unexpectedly revealed that predicted epitope presentation by multiple class I HLAs of a subject (PEPI2+, PEPI3+, PEPI4+, PEPI5+, or PEPI6), was in every case a better predictor of the CD8+ T cell response or CTL response than epitope presentation by merely one or more HLA class I (PEPI1+, AUC=0.48, Table 6).
The CTL response of an individual was best predicted by considering the epitopes of an antigen that could be presented by at least 3 HLA class I alleles of an individual (PEPI3+, AUC=0.65, Table 7). The threshold count of PEPI3+(number of antigen-specific epitopes presented by 3 or more HLA of an individual) that best predicted a positive CTL response was 1 (Table 7). In other words, at least one antigen-derived epitope is presented by at least 3 HLA class I of a subject (≥1 PEPI3+), then the antigen can trigger at least one CTL clone, and the subject is a likely CTL responder. Using the ≥1 PEPI3+ threshold to predict likely CTL responders (“≥1 PEPI3+ test”) provided 76% true positive rate (diagnostic sensitivity) (Table 7).
In a retrospective analysis, the test cohort of 81 datasets from 51 patients was used to validate the ≥1 PEPI3+ threshold to predict an antigen-specific CD8+ T cell response or CTL response. For each dataset in the test cohort it was determined whether the ≥1 PEPI3+ threshold was met (at least one antigen-derived epitope presented by at least three class I HLA of the individual). This was compared with the experimentally determined CD8+ T cell responses (CTL responses) reported from the clinical trials (Table 8).
The retrospective validation demonstrated that a PEPI3+ peptide induces CD8+ T cell response (CTL response) in an individual with 84% probability. 84% is the same value that was determined in the analytical validation of the PEPI3+ prediction, epitopes that binds to at least 3 HLAs of an individual (Table 4). These data provide strong evidences that immune responses are induced by PEPIs in individuals.
ROC analysis determined the diagnostic accuracy, using the PEPI3+ count as cut-off values (
A PEPI3+ count of at least 1 (≥1 PEPI3+) best predicted a CTL response in the test dataset (Table 9). This result confirmed the threshold determined during the training (Table 6).
The PEPI3+ biomarker-based vaccine design has been tested first time in a phase I clinical trial in metastatic colorectal cancer (mCRC) patients in the OBERTO phase I/II clinical trial (NCT03391232). In this study, we evaluated the safety, tolerability and immunogenicity of a single or multiple dose(s) of PolyPEPI1018 as an add-on to maintenance therapy in subjects with mCRC. PolyPEPI1018 is a peptide vaccine containing 12 unique epitopes derived from 7 conserved TSAs frequently expressed in mCRC (WO2018158455 A1). These epitopes were designed to bind to at least three autologous HLA alleles that are more likely to induce T-cell responses than epitopes presented by a single HLA (See Examples 2 & 3). mCRC patients in the first line setting received the vaccine (dose: 0.2 mg/peptide) just after the transition to maintenance therapy with a fluoropyrimidine and bevacizumab. Vaccine-specific T-cell responses were first predicted by identification of PEPI3+-s in silico (using the patient's complete HLA genotype and antigen expression rate specifically for CRC) and then measured by ELISpot after one cycle of vaccination (phase I part of the trial).
Seventy datasets from 10 patients (Phase 1 cohort and dataset of OBERTO trial) was used to prospectively validate that PEPI3+ biomarker predicts antigen-specific CTL responses. For each dataset, predicted PEPI3+-s were determined in silico and compared to the vaccine-specific immune responses measured by ELISPOT assay from the patients' blood. Diagnostic characteristics (positive predictive value, negative predictive value, overall percent agreement) determined this way were then compared with the retrospective validation results described in Example 3.
The overall percent agreement was 64%, with high positive predictive value of 79%, representing 79% probability that the patient with predicted PEPI3+ will produce CD8 T cell specific immune response against the analyzed antigen. Clinical trial data were significantly correlated with the retrospective trial results (p=0.01) and provides evidence for the PEPI3+ calculation with PEPI test to predict antigen-specific T cell responses based on the complete HLA-genotype of patients (Table 10).
It is hypothesized that tumor specific antigens (TSAs) are immune-protective antigens because cancer patients with spontaneous TSA specific T cell responses have favourable clinical course. 48 TSAs expressed in different tumor types were selected to study protective tumor specific T cell responses (Table 11). These TSAs have been studied in melanoma and other cancers and showed to induce spontaneous T cell responses.
Incidence Rate for Melanoma Correlates with HLAT Number Indicating the Breadth of Melanoma Specific T Cell Responses
It is hypothesized that the HLAT number for the 48 TSAs in a population where melanoma has high incidence rate would be lower than in a population with high incidence rate. To show this the HLAT number for the 48 TSAs was determined in different ethnic populations for which melanoma incidence are available (
Subjects in the far East Asian/Pacific region were found to have much higher HLAT numbers than subjects of European or US origin (
HLAT Scores (s) are in agreement with the incidence rate of melanoma in different countries (
HLAT numbers predicted the breadth of T cell responses against 48 selected TSAs. It is hypothesized that not all the HLATs of a subject play equally important role in the immunological control of melanoma. Therefore, the HLATs (for the 48 TSAs) were weighted based on capacity to separate melanoma patients from a general population. In general, the larger the weight, the more important is the corresponding TSA. Indeed, the AUC was already above 0.6 using the initial weights (truncated log p-values).
Performance of a Binary Classifier at Separating Melanoma Patients from the Background
This study compared a US subpopulation (n=1400) from the dbMHC dataset (7,189 patient cohort) to melanoma subjects, also with US origin (n=513) using a binary classifier (see Methods).
The AUC value obtained was 0.645. This value indicates a significant separation between two groups, in particular because in the case of melanoma/cancer incidence there is not only a single cause (e.g. HLAT) of discrimination. Most remarkably sun and indoor tanning exposure is a significant determinant of melanoma risk, as are phenotypes such as blond or red hair, blue eyes and freckles and genetic factors such as the high penetrance, 3 medium penetrance and 16 low penetrance genes associated to melanoma described by Read et al. (J. Med. Genet. 2016; 53(1): 1-14). Indeed, the transformed z score of 10.065 achieved in the present study is highly significant (p<0.001).
The total test population (background population mixed with cancer population) was divided into five equally large groups based on HLAT Score. The Relative Immunological Risk (RiR) in each group was determined compared to the risk in an average US population (
A similar analysis was performed for six other cancer indications. The results are summarised in Table 12. The AUC values were significant for melanoma, lung cancer, renal cell carcinoma, colorectal cancer and bladder cancer. The p value is not significant for head and neck cancer. However, head and neck cancer is associated with viral HPV infection. Only TSAs were used in the present study, no viral proteins were included. It may be that the risk of developing certain cancers, such as head and neck cancer, that can be associated with viral infections could better be determined by including viral antigens in the analysis.
By dividing the test population (background population mixed with cancer population) into five equally large subgroups based on the HLAT Scores, we could calculate the relative immunological risk associated with certain HLAT Scores in case of non-small cell lung cancer, renal cell carcinoma and colorectal cancer (
The relative immunological risk ratio was calculated between the Risk subgroup (20% of the test population with the lowest HLAT Score) and the Protected subgroup (20% of the test population with the highest HLAT Score) compared to the risk in an average US population. For example, the risk of developing melanoma in the characterized riskiest subpopulation is 4.4%. The US average is 2.4%, therefore, the Risk group has a 1.7 relative immunological risk. The risk of developing melanoma in the Protected group is 0.7%. That is, the relative immunological risk of the most protected group is 0.31. In other words, this group has more than three times lower risk to develop melanoma compared to the average population. The risk ratio achieved for melanoma is 5.53 (Table 12).
7,189 eligible subjects with complete 4-digit HLA genotype were identified from dbMHC database. The ethnicity of each subject was indicated. Our analysis revealed that the HLA background of subpopulations coming from different geographic regions differ considerably. To eliminate this geographic effect, we selected the American subpopulation (1400 subjects) as a background (healthy) population, and the HLA sets of this subgroup were compared to the HLA sets of geographically/ethnically matched cancer subjects. The American subpopulation consists of all Caucasian, Hispanic, Asian-American, African-American and native ethnics.
Eligible patients had complete 4-digit HLA class I genotype. Data from 513 patients with melanoma were obtained from the following sources:
429 melanoma subjects were available with complete 4-digit HLA class I genotype from 3 peer-reviewed publications (Snyder et al. N Engl J Med. 2014; 371(23):2189-99; Van Allen et al. Science. 2015; 350(6257):207-11; Chowell et al. Science. 2018; 359(6375):582-7). Patients were treated with anti-CTLA-4 and/or PD-1/PD-L1 inhibitors at the Memorial Sloan Kettering Cancer Center, New York (MSKCC). High-resolution HLA class I genotyping from normal DNA was performed using DNA sequencing data or clinically validated HLA typing assay by LabCorp. 17 stage III/IV melanoma patients' HLA genotype was kindly provided by MSKCC. These patients were treated with Ipilimumab at MSKCC, New York (Yuan et al. Proc Natl Acad Sci USA. 2011; 108(40):16723-8). 65 melanoma patients from a phase 3 randomized, double-blind, multicenter study (CA184007, NCT00135408) and a phase 2 (CA184002, NCT00094653) in patients with unresectable stage III or IV malignant melanoma and previously treated unresectable stage III or stage IV melanoma, correspondingly. These 65 patients treated at MSKCC, New York site had samples available for HLA testing which were kindly provided by Bristol-Myers-Squibb. Samples were retrospectively tested with NGS G group resolution and HLA allele interpretation was based on IMGT/HLA database version 3.15. HLA results were obtained using sequence based typing (SBT), sequence specific oligonucleotide probes (SSOP), and/or sequence specific primers (SSP) as needed to obtain the required resolution. The HLA testing was performed by LabCorp, USA.
HLA genotype data of 370 patients with non-small cell lung cancer, 129 renal cell carcinoma, 87 bladder cancer, 82 glioma and 58 head and neck cancer subjects were collected from peer reviewed publication (Chowell et al.).
Data from 37 colorectal cancer (CRC) patients' HLA genotype were obtained from the National Center for Biotechnology (NCBI) Sequence Read Archive, Encyclopedia of deoxyribonucleic acid elements (Boegel et al. Oncoimmunology. 2014; 3(8):e954893). Blood samples from 211 Vietnamese and 84 white, non-Hispanic CRC patients were obtained from Asterand Bioscience and HLA genotype were identified by LabCorp (Burlington N.C.).
48 TSAs were selected. The amino acid sequence data of these antigens were obtained from UniProt.
Incidence rates were obtained from globocan.iarc.fr/Pages/online.aspx,
HLA class I genes are expressed in most cells and bind to epitopes that are recognized by T cell receptors. Epitopes that bind to at least three HLAs (HLA triplet or HLAT) of a person's six HLA alleles can generate T cell responses. For each j=1, 2, . . . 6 we set up a scoring system to score the subjects' immune system based on how well they can bind epitopes. Based on combinatorics, there are
possible HLA allele j-sets for a particular epitope, where k is the number of autologous HLA alleles that can bind the epitope. When we are interested in HLA triplets, j=3. Therefore, HLAT number of a subject for an antigen is defined as the total sum of HLATs.
HLATs of subjects are identified with the PEPI test, validated to identify HLA binding epitopes with 93% accuracy.
The HLAT Score of a subject x is defined:
s(x)=Σc∈Cw(c)p(x,c) (1)
where C is the set of the TSAs, c is a particular TSA, w(c) is the weight of TSA c, and p(x,c) is the HLAT number of the TSA c in subject x.
The initial weight was 0 for each TSA whose HLAT Scores did not significantly separated cancer patients from the background population. Since we assumed that having HLATs do not increase the chance to develop cancer, only non-negative weights were considered. The initial weights were defined as
where t(c) denotes the p-value of the one sided t-test on the HLAT Score of the TSA c of the cancer and background populations and 48 is the Bonferroni correction.
The initial weights were further optimized using the Parallel Tempering. Six parallel Markov chains has been applied with temperatures RT=0.001, 0.01, 0.02, 0.04, 0.1, 0.2. The hypothetical energy was defined as −1 times the sum of the RiRR (Relative immunological risk ratio, see below) and AUC. The weights providing the largest relative risk ratio has been reported.
RiR was calculated by the ratio of the risks between a subpopulation and the total test population (cancer population and background population) with the 95% confidence intervals (CI). For this purpose, the general population was assembled in that way to resemble the percentage of different cancer patients in a general US population taking into consideration the life-time risk. The lifetime risks of developing the different type of cancers was obtained from the website of the American Cancer Society. Typically, the lifetime risk of men and women differ, so we took the (harmonic) average of them. The so-obtained risks are: 1:38 for melanoma, 1:16 for lung cancer, 1:61 for renal cell carcinoma, 1:23 for colorectal cancer, 1:41 for bladder cancer, 1:55 for head and neck cancer and 1:161 for glioma. RiR>1 indicates that subjects have higher risk of developing a certain cancer compared to subjects in an average population.
RiR Ratio was calculated as the ratio between the groups with the highest and lowest HLAT Scores.
When developing a screening test, we considered several scoring schemes. The potential scoring schemes differ in the minimum size of HLA allele sets binding to one particular epitope that is considered to contribute to the score of a subject. For each size of HLA allele subsets j=1, 2, . . . , 6, we computed the significance scores for each allele based on how frequently it participates in HLA j-tuples of the training subjects binding to a particular epitope. Briefly, we considered the significance score positive, if subjects with a given HLA allele had significantly more epitopes with HLA j-mers than subjects without the given HLA allele. The significance score was negative if the subjects with the given HLA allele had significantly less epitopes with HLA j-mers than the subjects without the given HLA allele. Then for each subject we summed the significance scores of his/her HLA alleles. Next, we tested how well these summed scores can distinguish melanoma and background subjects by computing the area under the receiver operating characteristic curve (ROC-AUC, AUC). According to Table 13, the best separation of melanoma and background population was achieved equally for j=2 and j=3. The remarkable difference between the AUC values for the different scores based on 1-set versus j-sets, j>1, suggest that presentation of an epitope by multiple HLA alleles could play an important role in developing efficient anti-tumor immune response. Furthermore, these results suggest that separation of cancer and background (healthy) subjects based on single allele of their HLA genotype would be challenging. The drop-off in the AUC values when j=6 can be explained with the fact that there are only a very limited number of epitope-HLA allele combinations where all the 6 HLA alleles of a subject can bind the epitope.
The AUC value (0.69) comparing US melanoma and background subjects indicates significant separation between the two groups, using the HLA-score. Indeed, the transformed z score was 12.57, which was highly significant (p<0.001). These results demonstrate that subjects' HLA genotype influence the genetic risk for developing melanoma. Based on the HLA-score, the background and melanoma populations were divided into five equal-size subgroups based on their HLA-score (s); s<34, 34≤s<55, 55≤s<76, 76≤s<96 and 96<s. The Relative Risk (RR) of each subgroup was computed (
We computed the risk ratio between the most protected and most at-risk groups (RRextremities). We found that the RRextremities for melanoma is 5.69 indicating that subjects with HLA-score less than 34 have approximately 6 fold higher risk of developing melanoma compared to subjects with HLA-score higher than 96 (Table 14).
In some cases the significance score of an HLA allele (h) is defined as
where u(h) is the p-value of the two-sided u-test for allele h determining whether or not the number of HLATs are different in two subsets of individuals: one subset in which the individuals have HLA h, and one subset in which the individuals do not have HLA h. B is the Bonferroni correction, and sign(h) is +1 if the average number of HLATs is larger in the subpopulation having the h allele than in the subpopulation not having h, and −1 otherwise. In some cases, this initial score may be further optimized using any suitable method as known to those skilled in the art. In some cases the sum of these significance scores is used to determine the risk that the subject will develop cancer correlates to the risk that the subject will develop cancer.
The concrete score to be used depends on the indication and the a priori data. In some cases, the choice will be made based on the performance of the different computations on available test datasets. The performance might be evaluated by the AUC value (the area under the ROC curve) or by any other goodness of performance score known by those skilled in the art.
We determined the ROC curve, RR and RRextremities for non-small cell lung, renal cell, colorectal, bladder, head and neck cancers and glioma using the same methods described for melanoma (Table 14). The ROC-AUC values were significant for all cancer types, except for colorectal cancer.
We obtained a RRextremities range of 2.35-5.69 for the studied cancer indications, suggesting different levels of immune protection against different types of cancer (Table 14). However, RRextremities>2 for all cancer indications demonstrate that HLA genotype represents a substantial genetic risk of developing cancer.
This example shows how to compute the HLAT Score of Patient-D described in Example 20. Patient-D has been diagnosed with metastatic colorectal cancer. Using patient-D's HLA genotype the predicted number of PEPI3, PEPI4, PEPI5 and PEPI6 epitopes on the 48 selected TSAs were determined (Table 15). Based on the statistics, the total number of HLATs for each TSA were computed (lines 6, 14 and 22 of Table 15) and the weighted scores for each TSA (lines 8, 16 and 24 of Table 15). This weighted score is simply the product of the total number of HLATs and the weights of the TSAs (lines 7, 15 and 23 of Table 15). The weights were obtained with the method described in the “HLAT Score Weight Optimization” section of Example 6. The summed weighted score (as described in Equation (1)) is 43.09. Based on the comparison of American CRC and American background population, Patient-D has a 1.26-fold risk to develop colorectal cancer than an average person in the USA. Since the risk for developing CRC in the USA is 4.2%, the risk for Patient-D based on our result is 5.3%.
In the OBERTO trial, we predicted immune response for 7 antigens and 11 subjects, and also measured immune responses in 10 patients' specimen. The 7 antigens of the vaccine are part of the 48 TSAs. The predictions and measurements are summarized in Table 16. The overall percentage agreement is 64%.
We compared the HLAT Scores and the number of antigens with the measured immune responses (
As can be seen, HLAT Score based classification is better in case of colorectal cancer, while HLA-score based classification works better in case of head and neck cancer.
To further demonstrate that the HLA genotype influences the risk of developing cancer also on population level, we investigated its relationship with country-specific incidence rates. We hypothesized that the average HLA-score, i.e. the cancer-specific T-cell responses of a population with a high incidence rate of melanoma would be substantially lower than the HLA-score of a population with a low incidence rate. Therefore, we determined the HLA-scores for subjects representative for 59 different countries. We found that subjects in the Far East Asian and Pacific region had considerably higher HLA-scores (range 75-140) and lower incidence rates (range 0.4-3.4) than subjects of European or US origin (range 50 and 90) where the incidence rate is the highest (range 12.6-13.8) (
These results suggest that the HLA genotypes of subjects influence the incidence rate of melanoma in different ethnic populations and consistently suggest that the HLA-score could be used to determine the immunogenetic risk for melanoma.
A*02:01, C*05:01, C*07:01 are HLA alleles that are associated with CLL (chronic lymphocytic leukemia) (Gragert et al, 2014) meaning, that subjects having any of these HLA class I alleles have increased risk of developing CLL. During the HLA-score training, we observed that subjects in the training population having any of these HLAs have significantly less HLATs for the analysed 48 TSAs than subjects not having these HLAs. Table 19 shows the average HLAT numbers for the 48 TSAs in case of the 9 most frequent HLA alleles. However, these few HLA alleles can be found only in a small fraction of the population, and thus, the information that can be gained from the association between cancer and these few alleles cannot be used for subjects not having any of these alleles. On the other hand, the HLA score method assigns an informative score to all subjects and therefore can be used to classify the entire population. Therefore, the HLA score method provides better classification than a method using only information about association between individual HLA alleles and cancer.
Example-15—One Allele or a Non-Complete HLA Genotype is not Appropriate to Determine Genetic Risk
It is known that Epstein-Barr virus (EBV) infection can induce undifferentiated nasopharyngeal carcinoma (UNPC). Pasini et al. analysed 82 Italian UNPC patients and 286 bone marrow donors from the same population and observed that some conserved alleles, A*0201, B*1801, and B*3501 HLA capable to bind to some EBV epitopes in the given region are underrepresented in UNPC subjects (Pasini E et al. Int. J. Cancer: 125, 1358-1364 (2009)). The investigation of the frequent alleles in the population, however is a completely different approach from the investigation of immune response inducing real target HLA-combinations, like HLAT pool analysis of the individuals. Since the latter suggests the potential of the person to produce diseased cell killing T cell repertoire, a mechanism explaining immunogenetic “advance” or risk. Furthermore, they found additive effect on protective HLA alleles. However, they did not infer if these HLA alleles can bind the same epitope or different epitopes on different EBV antigens. They also found HLA alleles which are positively associated to UNPC, however, they could not measure decreased ability of these HLA alleles to bind EBV epitopes. They considered only antigens from EBV, therefore their methods cannot be generalized to other cancers. Since even the most frequent HLA alleles cover only a limited fraction of the entire population, diagnostic devices cannot be constructed based on only them. For example, a device based on only the A*02:01 allele could have only an AUC value of 0.573 (
OBERTO trial is a Phase I/II tria of PolyPEPI1018 Vaccine and CDx for the Treatment of Metastatic Colorectal Cancer (NCT03391232). Study design is shown on
Shared tumor antigens enable precise targeting of all tumor types—including the ones with low mutational burden. Population expression data collected previously from 2,391 CRC biopsies represents the variability of antigen expression in CRC patients worldwide (
PolyPEPI1018 is a peptide vaccine we designed to contain 12 unique epitopes derived from 7 conserved testis specific antigens (TSAs) frequently expressed in mCRC. In our model we supposed, that by selecting the TSA frequently expressed in CRC, the target identification will be correct and will eliminate the need for tumor biopsy. We have calculated that the probability of 3 out of 7 TSAs being expressed in each tumor is greater than 95%. (
In a phase I study we evaluated the safety, tolerability and immunogenicity of PolyPEPI1018 as an add-on to maintenance therapy in subjects with metastatic colorectal cancer (mCRC) (NCT03391232) (See also in Example 4).
Immunogenicity measurements proved pre-existing immune responses and indirectly confirmed target antigen expression in the patients. Immunogenicty was measured with enriched Fluorospot assay (ELISPOT) from PBMC samples isolated prior to vaccination and in different time points following a following single immunization with PolyPEPI1018 to confirm vaccine-induced T cell responses; PBMC samples were in vitro stimulated with vaccine-specific peptides (9mers and 30mers) to determine vaccine-induced T cell responses above baseline. In average 4, at least 2 patients had pre-existing CD8 T cell responses against each target antigen (
PolyPEPI1018 vaccine contains six 30mer peptides, each designed by joining two immunogenic 15mer fragments (each involving a 9mer PEPI, consequently there are 2 PEPIs in each 30mer by design) derived from 7 TSAs (
Preclinical immunogenicity results calculated for the Model Population (n=433) and for a CRC cohort (n=37) resulted in 98% and 100% predicted immunogenicity based on PEPI test predictions and this was clinically proved in the OBERTO trial (n=10), with immune responses measured for at least one antigen in 90% of patients. More interestingly, 90% of patients had vaccine peptide specific immune responses against at least 2 antigens and 80% had CD8+ T cell response against 3 or more different vaccine antigens, showing evidence for appropriate target antigen selection during the design of PolyPEPI1018. CD4+ T cell specific and CD8+ T cell specific clinical immunogenicity is detailed in Table 21. High immune response rates were found for both effector and memory effector T cells, both for CD4+ and CD8+ T cells, and 9 of 10 patients' immune responses were boosted or de novo induced by the vaccine. Also, the fractions of CRC-reactive, polyfunctional CD8+ and CD4+ T cells have been increased in patient's PBMC after vaccination by 2.5- and 13-fold, respectively.
The OBERTO clinical trial (NCT03391232), that has been further described in Examples 4, 16, 17 and 18 was analyzed for preliminary objective tumor response rates (RECIST 1.1) (
After one vaccination, ORR was 27%, DCR was 63%, and in patients receiving at least 2 doses (out of the 3 doses), 2 of 5 had ORR (40%) and DCR was as high as 80% (SD+PR+CR in 4 out of 5 patients) (Table 22).
Based on the data of the 5 patients receiving multiple doses of PolyPEPI1018 vaccine in the OBERTO-101 clinical trial, preliminary data suggests that higher AGP count (>2) is associated with longer PFS and elevated tumor size reduction (
This Example provides proof of concept data from 4 metastatic cancer patients treated with personalized immunotherapy vaccine compositions to support the principals of binding of epitopes by multiple HLAs of a subject to induce cytotoxic T cell responses, on which the present disclosure is partly based on.
Composition for Treatment of Ovarian Cancer with P0001-PIT (Patient-A)
This example describes the treatment of an ovarian cancer patient with a personalised immunotherapy composition, wherein the composition was specifically designed for the patient based on her HLA genotype based on the disclosure described herein.
The HLA class I and class II genotype of a metastatic ovarian adenocarcinoma cancer patient (Patient-A) was determined from a saliva sample.
To make a personalized pharmaceutical composition for Patient-A thirteen peptides were selected, each of which met the following two criteria: (i) derived from an antigen that is expressed in ovarian cancers, as reported in peer reviewed scientific publications; and (ii) comprises a fragment that is a T cell epitope capable of binding to at least three HLA class I of Patient-A (Table 23). In addition, each peptide is optimized to bind the maximum number of HLA class II of the patient.
Eleven PEPI3 peptides in this immunotherapy composition can induce T cell responses in Patient-A with 84% probability and the two PEPI4 peptides (P0001-P2 and P0001-P5) with 98% probability, according to the validation of the PEPI test shown in Table 4. T cell responses target 13 antigens expressed in ovarian cancers. Expression of these cancer antigens in Patient-A was not tested. Instead the probability of successful killing of cancer cells was determined based on the probability of antigen expression in the patient's cancer cells and the positive predictive value of the ≥1 PEPI3+ test (AGP count). AGP count predicts the effectiveness of a vaccine in a subject: Number of vaccine antigens expressed in the patient's tumor (ovarian adenocarcinoma) with PEPI. The AGP count indicates the number of tumor antigens that the vaccine recognizes and induces a T cell response against the patient's tumor (hit the target). The AGP count depends on the vaccine-antigen expression rate in the subject's tumor and the HLA genotype of the subject. The correct value is between 0 (no PEPI presented by any expressed antigen) and maximum number of antigens (all antigens are expressed and present a PEPI).
The probability that Patient-A will express one or more of the 13 antigens is shown in
A pharmaceutical composition for Patient-A may be comprised of at least 2 from the 13 peptides (Table 23), because the presence in a vaccine or immunotherapy composition of at least two polypeptide fragments (epitopes) that can bind to at least three HLAs of an individual (≥2 PEPI3+) was determined to be predictive for a clinical response. The peptides are synthetized, dissolved in a pharmaceutically acceptable solvent and mixed with an adjuvant prior to injection. It is desirable for the patient to receive personalized immunotherapy with at least two peptide vaccines, but preferable more to increase the probability of killing cancer cells and decrease the chance of relapse.
For treatment of Patient-A, the 13 peptides were formulated as 4×3 or 4 peptide (P0001/1, P0001/2, P0001/3, P0001/4). One treatment cycle is defined as administration of all 13 peptides within 30 days.
Diagnosis: Metastatic ovarian adenocarcinoma
Family anamnesis: colon and ovary cancer (mother) breast cancer (grandmother)
2011: first diagnosis of ovarian adenocarcinoma; Wertheim operation and chemotherapy; lymph node removal
2015: metastasis in pericardial adipose tissue, excised
2016: hepatic metastases
2017: retroperitoneal and mesenteric lymph nodes have progressed; incipient peritoneal carcinosis with small accompanying ascites
2016-2017 (9 months): Lymparza (Olaparib) 2×400 mg/day, oral
2017: Hycamtin inf. 5×2.5 mg (3× one seria/month)
PIT vaccine treatment began on 21 Apr. 2017.
2017-2018: Patient-A received 8 cycles of vaccination as add-on therapy, and lived 17 months (528 days) after start of the treatment. During this interval, after the 3rd and 4th vaccine treatment she experienced partial response as best response. She died in October 2018.
An interferon (IFN)-γ ELISPOT bioassay confirmed the predicted T cell responses of Patient-A to the 13 peptides. Positive T cell responses (defined as >5 fold above control, or >3 fold above control and >50 spots) were detected for all 13 20-mer peptides and all 13 9-mer peptides having the sequence of the PEPI of each peptide capable of binding to the maximum HLA class I alleles of Patient-A (
Patient’ tumor MRI findings (Baseline Apr. 15, 2016) (BL: baseline for tumor response evaluation on
Disease was confined primarily to liver and lymph nodes. The use of MRI limits detection of lung (pulmonary) metastasis
May 2016-January 2017: Olaparib treatment (FU1: follow up 1 on
Dec. 25, 2016 (before PIT vaccine treatment) There was dramatic reduction in tumor burden with confirmation of response obtained at (FU2: follow up 2 on
January-March 2017—TOPO protocol (topoisomerase)
Apr. 6, 2017 (FU3 on
Jul. 26, 2017 (after the 2nd Cycle of PIT): (FU4 on
October 2018: Patient-A died
Partial MRI data for Patient-A is shown in Table 24 and
The HLA class I and class II genotype of metastatic breast cancer Patient-B was determined from a saliva sample. To make a personalized pharmaceutical composition for Patient-B twelve peptides were selected, each of which met the following two criteria: (i) derived from an antigen that is expressed in breast cancers, as reported in peer reviewed scientific publications; and (ii) comprises a fragment that is a T cell epitope capable of binding to at least three HLA class I of Patient-B (Table 25). In addition, each peptide is optimized to bind the maximum number of HLA class II of the patient. The twelve peptides target twelve breast cancer antigens. The probability that Patient-B will express one or more of the 12 antigens is shown in
Predicted efficacy: AGP95=4; 95% likelihood that the PIT Vaccine induces CTL responses against 4 TSAs expressed in the breast cancer cells of Patient-B. Additional efficacy parameters: AGP50=6.45, mAGP=100%, AP=12.
For treatment of Patient-B the 12 peptides were formulated as 4×3 peptide (PBR01/1, PBR01/2, PBR01/3, PBR01/4). One treatment cycle is defined as administration of all 12 different peptide vaccines within 30 days (
2013: Diagnosis: breast carcinoma diagnosis; CT scan and bone scan ruled out metastatic disease.
2014: bilateral mastectomy, postoperative chemotherapy
2016: extensive metastatic disease with nodal involvement both above and below the diaphragm. Multiple liver and pulmonary metastases.
2017: Letrozole, Palbocichb and Gosorelin and PIT vaccine
2018: Worsening conditions, patient died in January
PIT vaccine treatment began on 7 Apr. 2017. treatment schedule of Patient-B and main characteristics of disease are shown in Table 26.
It was predicted with 95% confidence that 8-12 vaccine peptides would induce T cell responses in Patient-B. Peptide-specific T cell responses were measured in all available PBMC samples using an interferon (IFN)-γ ELISPOT bioassay (
Mar. 7, 2017: Prior PIT Vaccine treatment
Hepatic multi-metastatic disease with truly extrinsic compression of the origin of the choledochal duct and massive dilatation of the entire intrahepatic biliary tract. Celiac, hepatic hilar and retroperitoneal adenopathy
March 2017: Treatment initiation—Letrozole, Palbociclib, Gosorelin & PIT Vaccine
May 2017: Drug interruption
May 26, 2017: After 1 cycle of PIT
83% reduction of tumor metabolic activity (PET CT) liver, lung lymphnodes and other metastases.
June 2017: Normalized Neutrophils values indicate Palbociclib interruption as affirmed by the patient
March to May 2017: CEA and CA remained elevated consistently with the outcome of her anti-cancer treatment (Ban, Future Oncol 2018)
June to September 2017: CEA and CA decreased consistently with the delayed responses to immunotherapies
February to March 2017: Poor, hospitalized with jaundice
November 2017: Worsening conditions (tumor escape?)
January 2018: Patient-B died.
Immunogenicity results are summarized in
Clinical outcome measurements of the patient: One month prior to the initiation of PIT vaccine treatment PET CT documented extensive DFG avid disease with nodal involvement both above and below the diaphragm (Table 26). She had progressive multiple hepatic, multifocal osseous and pulmonary metastases and retroperitoneal adenopathy. Her intrahepatic enzymes were elevated consistent with the damage caused by her liver metastases with elevated bilirubin and jaundice. She accepted Letrozole, Palbociclib and Gosorelin as anti-cancer treatment. Two month after initiation of PIT vaccinations the patient felt very well and her quality of life normalized. In fact, her PET CT showed a significant morphometabolic regression in the liver, lung, bone and lymph node metastases. No metabolic adenopathy was identifiable at the supra-diaphragmatic stage.
The combination of Palblocyclib and the personalised vaccine was likely to have been responsible for the remarkable early response observed following administration of the vaccine. Palbocyclib has been shown to improve the activity of immunotherapies by increasing TSA presentation by HLAs and decreasing the proliferation of Tregs (Goel et al. Nature. 2017:471-475). The results of Patient-B treatment suggest that PIT vaccine may be used as add-on to the state-of-art therapy to obtain maximal efficacy.
Patient-B's tumor biomarkers were followed to disentangle the effects of state-of-art therapy from those of PIT vaccine. Tumor markers were unchanged during the initial 2-3 months of treatment then sharply dropped suggesting of a delayed effect, typical of immunotherapies (Table 26). Moreover, at the time the tumor biomarkers dropped the patient had already voluntarily interrupted treatment and confirmed by the increase in neutrophil counts.
After the 5th PIT treatment the patient experienced symptoms. The levels of tumor markers and liver enzymes were increased again. 33 days after the last PIT vaccination, her PET CT showed significant metabolic progression in the liver, peritoneal, skeletal and left adrenal site confirming the laboratory findings. The discrete relapse in the distant metastases could be due to potential immune resistance; perhaps caused by downregulation of both HLA expression that impairs the recognition of the tumor by PIT induced T cells. However, the PET CT had detected complete regression of the metabolic activity of all axillary and mediastinal axillary supra-diaphragmatic targets (Table 26). These localized tumor responses may be accounted to the known delayed and durable responses to immunotherapy, as it is unlikely that after anti-cancer drug treatment interruption these tumor sites would not relapse.
Personalised Immunotherapy Composition for Treatment of a Patient with Metastatic Breast Carcinoma (Patient-C)
PIT vaccine similar in design to that described for Patient-A and Patient-B was prepared for the treatment of a patient (Patient-C) with metastatic breast carcinoma. PIT vaccine contained 12 PEPIs. The PIT vaccine has a predicted efficacy of AGP=4. The patient's treatment schedule is shown in
2011 Original tumor: HER2-, ER+, sentinel lymph node negative
2017 Multiple bone metastases: ER+, cytokeratin 7+, cytokeratin 20−, CA125−, TTF1−, CDX2−
2011 Wide local resection, sentinel lymph nodes negative; radiotherapy
2017—Anti-cancer therapy (Tx): Letrozole (2.5 mg/day), Denosumab;
Bioassay confirmed positive T cell responses (defined as >5 fold above control, or >3 fold above control and >50 spots) to 11 out of the 12 20-mer peptides of the PIT vaccine and 11 out of 12 9-mer peptides having the sequence of the PEPI of each peptide capable of binding to the maximum HLA class I alleles of the patient (
Clinical results of treatment of Patient-C are shown in Table 27. Patient-C has partial response and signs of healing bone metastases.
Immune responses are shown on
Detected Immunogenicity: 11 (20-mers) & 11 (9-mers) antigen specific T cell responses following 3 PIT vaccinations (
Personalised Immunotherapy Composition for Treatment of Patient with Metastatic Colorectal Cancer (Patient-D)
The patient's treatment schedule is shown in
Patient in good overall condition, disease progression in lungs after 8 months confirmed by CT.
Both PIT induced and pre-existing T cell responses were measured by enriched Fluorospot from PBMC, using 9mer and 20mer peptides for stimulation (
Summary of immune response rate and immunogenicity results prove the proper design for target antigen selection as well as for the induction of multi-peptide targeting immune responses, both CD4+ and CD8+ specific ones.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1814361.0 | Sep 2018 | GB | national |
This application is the U.S. National Stage entry of International Application No. PCT/EP2019/073478, filed on Sep. 3, 2019, which claims the benefit of and priority to UK Application No. 1814361.0, filed on Sep. 4, 2018, each of which are incorporated herein by reference in their entireties.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2019/073478 | 9/3/2019 | WO | 00 |
