Methods of treating cancer

Abstract

The invention relates to new methods and approaches for the treatment of cancers, particularly cancers expressing TP53 mutations, comprising the administration of a Sting agonist, and either an anti-cancer immunotherapy, or a TP53 targeting cancer therapy.

Description

Methods of treating cancer

[0001] This application claims priority to Australian application no 2024903254 (filed 9 October 2024), the entire contents of which is incorporated herein by reference.Field of the invention

[0002] The present invention relates to methods and compositions for treating cancers, particularly cancers expressing mutant forms of TP53.Background of the invention

[0003] Survival rates for many cancers have improved significantly over the last decade as a result of improvements in molecular profiling and novel therapeutic approaches to tackle these malignancies.

[0004] However, tumour suppressor gene TP53 (also called TRP53 in mice or p53 generally) mutant disease remains a major clinical challenge for treatment of cancer. TP53 is the most commonly mutated gene across all cancer types, but TP53 mutant cancers are particularly resistant to cytotoxic drugs that depend on causing DNA damage to trigger cancer cell death. TP53 mutant cancer cells frequently also harbour defects in a broad range of pathways, including metabolism, genome stability and autophagy, conferring reduced sensitivity to diverse anti-cancer agents. For blood cancers, such as lymphoma and leukaemia, patient sub-groups bearing TP53 mutations in their malignant cells are generally considered to have adverse risk and inferior survival outcomes. TP53 mutations are found in 5-15% of acute myeloid leukemias (AML) (up to 25% in elderly patients), 25% of Non-Hodgkin lymphomas (NHL), and up to 60% of natural killer / T (NKT) cell lymphoma cases in some populations.

[0005] Effective treatment approaches for TP53 mutated cancers, and especially for TP53 mutated blood cancers, therefore, currently represents an urgent and inadequately addressed clinical need. There is therefore a need for new approaches and methods for the treatment of TP53 mutated cancers.

[0006] Reference to any prior art in the specification is not an acknowledgment or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be understood,1006167084regarded as relevant, and / or combined with other pieces of prior art by a skilled person in the art.Summary of the invention

[0007] The present invention is based on a surprising discovery by the inventors that TP53 mutation in leukemic cells impairs HLA expression on those cells. Thus, the inventors have identified a mechanism by which TP53 mutations promote immunoevasion of cancer cells. Importantly, the inventors found that treatment of cancer cells with a STING agonist restores HLA expression (particularly HLA-ABC expression). Accordingly, the present invention provides new methods and approaches for the treatment of cancers in which HLA expression is impaired by TP53 mutation.

[0008] Accordingly, in a first aspect, the present invention provides a method of restoring and / or increasing HLA expression in cancer cells, the method comprising administering to a subject in need thereof, a STING agonist, thereby restoring and / or increasing HLA expression in cancer cells of the subject. Preferably the cancer cells comprise a TP53 mutation, accordingly, in one embodiment there is provided a method of restoring and / or increasing HLA expression in TP53 mutant cancer cells, the method comprising administering to a subject in need thereof, a STING agonist, thereby restoring and / or increasing HLA expression in the TP53 mutant cancer cells of the subject.

[0009] According to a further aspect of the present invention, there is provided a method of inducing an immune response in a subject receiving a treatment for cancer, wherein the immune response comprises increased presentation of HLA complexes on cancer cells, the method comprising: administering to the subject a STING agonist, thereby eliciting the immune response in the subject. The method may comprise coadministering to the subject a synergistic combination of: an anti-cancer immunotherapy and a STING agonist. In one embodiment, there is provided a method of inducing an immune response to cancer in a subject, wherein the immune response comprises increased presentation of HLA complexes on cancer cells, the method comprising: coadministering to the subject an immunotherapy and a STING agonist, thereby eliciting the immune response in the subject. The method may comprise administering to the subject a synergistic combination of the anti-cancer immunotherapy and the STING agonist.1006167084

[0010] In a further aspect, the invention provides a method of potentiating an anticancer immunotherapy, the method comprising administering a STING agonist to a subject who has received, is receiving or is to receive an anti-cancer immunotherapy, thereby potentiating the anti-cancer immunotherapy.

[0011] Further, the invention provides a method of treating cancer comprising coadministering to the subject a synergistic combination of: an anti-cancer immunotherapy and a STING agonist.

[0012] In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: an anticancer immunotherapy and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising coadministering to the subject a synergistic combination of: an anti-cancer immunotherapy and a STING agonist. In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: anti-cancer immunotherapy; and a STING agonist, wherein the cancer comprises a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject a synergistic combination of: an anti-cancer immunotherapy and a STING agonist, wherein the cancer comprises a TP53 mutation.

[0013] In a particularly preferred embodiment, the cancer is a leukemia, such as acute myeloid leukemia (AML), expressing a TP53 mutation. Accordingly, the invention also provides, a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject: an anti-cancer immunotherapy and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: an anti-cancer immunotherapy and a STING agonist. In a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising coadministering to the subject: an anti-cancer immunotherapy and a STING agonist, wherein the AML cells comprise a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: an anti-cancer immunotherapy and a STING agonist, wherein the AML cells comprise a TP53 mutation.1006167084

[0014] In any aspect herein, the anti-cancer immunotherapy may be any suitable immunotherapy for treating cancer, but will be understood to typically be a therapy that requires presentation of HLA: peptide complexes to elicit a therapeutic effect.

[0015] Optionally, the immunotherapy may comprise an immune checkpoint inhibitor (such as an anti-PD-1 , an anti-PD-L1 or an anti-CTLA4 antibody), or may be an immunomodulator. The immunotherapy may comprise an antigen binding protein for binding to immune cells. For example, the immunotherapy may comprise a multispecific T-cell engager molecule (eg a bispecific or trispecific molecule for binding to a T cell and to a tumour antigen as is known in the art).

[0016] The immunotherapy may comprise a genetically modified immune cell, such as a genetically modified T, NKT cell or the like. Optionally, the immunotherapy comprises a CAR-T cell, including a CAR-T cell for use in the treatment of AML (such as an anti- CD33 CAR-T cell).

[0017] Further still, the immunotherapy may comprise a dendritic cell-based therapy.

[0018] In certain embodiments, the anti-cancer immunotherapy comprises a TP53- targeting vaccine therapy or TP53-targeting antigen binding protein therapy. The TP53 vaccine therapy may be an mRNA vaccine, peptide vaccine, viral vaccine (such as recombinant adenovirus or vaccinia Ankara) or dendritic cell based vaccine. Various p53-targeting vaccines are known in the art, and are described, for example in Zhou et al., (2021 ) Frontiers in Cell and Developmental Biology, 9:762796, and Hassin et al., (2023) Nature Reviews Drug Discovery, 22: 127-144, both of which are incorporated herein by reference. The TP53-targeting antigen binding protein therapy may be any therapy including an antigen binding protein for targeting / binding to TP53. Examples of such antigen binding protein therapies are disclosed in Hassin et al., (2023) Nature Reviews Drug Discovery, 22: 127-144, incorporated herein by reference. In non-limiting examples, the therapy may comprise an antibody, or a cell-based therapy comprising an antigen binding domain (such as CAR-T therapy). The antibody therapy may comprise a bispecific antibody or antigen binding fragment thereof, such as a bispecific T cell engager molecule. In one non-limiting example, the bispecific antibody is as described in Hsiue et al., (2021 ), Science, 371 : 6533, incorporated herein by reference.1006167084

[0019] In a further aspect there is provided a method of potentiating a TP53-targeted cancer therapy, the method comprising administering a STING agonist to a subject who has received, is receiving or is about to receive a TP53-targeted cancer therapy, thereby potentiating the TP53-targeted cancer therapy in the subject.

[0020] In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53- targeting therapy and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting therapy and a STING agonist. In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53- targeting therapy; and a STING agonist, wherein the cancer comprises a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting therapy and a STING agonist, wherein the cancer comprises a TP53 mutation.

[0021] In a particularly preferred embodiment, the cancer is a leukemia, such as acute myeloid leukemia (AML), expressing a TP53 mutation. Accordingly, the invention also provides, a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject: a TP53-targeting therapy; and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting therapy and a STING agonist. In AML, in a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53-targeting therapy; and a STING agonist, wherein the AML cells comprise a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting therapy and a STING agonist, wherein the AML cells comprise a TP53 mutation.

[0022] In any embodiment of any aspect herein, the TP53-targeted therapy may be any therapy that targets TP53:HLA complexes, or requires presentation of TP53:HLA complexes for efficacy, such as but not limited to a TP53 vaccine therapy or TP53- targeting antigen binding protein therapy. The TP53 vaccine therapy may be an mRNA1006167084vaccine, peptide vaccine, viral vaccine (such as recombinant adenovirus or vaccinia Ankara) or dendritic cell based vaccine. Various p53-targeting vaccines and therapies are known in the art, and are described, for example in Zhou et al., (2021 ) Frontiers in Cell and Developmental Biology, 9:762796, and Hassin et al., (2023) Nature Reviews Drug Discovery, 22: 127-144, both of which are incorporated herein by reference. The TP53-targeting antigen binding protein therapy may be any therapy including an antigen binding protein for targeting / binding to TP53 or TP53 neoantigens bound to HLAs. In non-limiting examples, the therapy may comprise an antibody, or a cell-based therapy comprising an antigen binding domain (such as CAR-T therapy). Examples of such antigen binding protein therapies are disclosed in Hassin et al., (2023) Nature Reviews Drug Discovery, 22: 127-144, incorporated herein by reference. The antibody therapy may comprise a bispecific antibody, or antigen binding fragment thereof (such as a bispecific T cell engager molecule). In one non-limiting example, the bispecific antibody is as described in Hsiue et al., (2021 ), Science, 371 : 6533, incorporated herein by reference.

[0023] Accordingly, in still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53-targeting vaccine; and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising coadministering to the subject a synergistic combination of: a TP53-targeting vaccine and a STING agonist. In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53-targeting vaccine; and a STING agonist, wherein the cancer comprises a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting vaccine and a STING agonist, wherein the cancer comprises a TP53 mutation.

[0024] In a particularly preferred embodiment of any aspect herein, the cancer is a leukemia, such as acute myeloid leukemia (AML), expressing a TP53 mutation. Accordingly, the invention also provides, a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject: a TP53-targeting vaccine; and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the1006167084subject a synergistic combination of: a TP53-targeting vaccine and a STING agonist. In AML a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53-targeting vaccine; and a STING agonist, wherein the AML cells comprise a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting vaccine and a STING agonist, wherein the AML cells comprise a TP53 mutation.

[0025] In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject: a TP53- targeting immunotherapy (such as an antigen binding protein therapy); and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting immunotherapy (such as an antigen binding protein therapy) and a STING agonist. In still a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising coadministering to the subject: a TP53-targeting immunotherapy (such as an antigen binding protein therapy); and a STING agonist, wherein the cancer comprises a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting immunotherapy (such as an antigen binding protein therapy) and a STING agonist, wherein the cancer comprises a TP53 mutation.

[0026] In a particularly preferred embodiment of any aspect herein, the cancer is a leukemia, such as acute myeloid leukemia (AML), expressing a TP53 mutation. Accordingly, the invention also provides, a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject: a TP53-targeting immunotherapy (such as an antigen binding protein therapy); and a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: a TP53-targeting immunotherapy (such as an antigen binding protein therapy) and a STING agonist. In AML a further aspect, there is provided a method of treating or inhibiting progression of cancer in a subject, comprising co-administering to the subject:1006167084a TP53-targeting immunotherapy (such as an antigen binding protein therapy); and a STING agonist, wherein the AML cells comprise a TP53 mutation. In one embodiment, there is provided a method of treating or inhibiting progression of AML in a subject, comprising co-administering to the subject a synergistic combination of: a TP53- targeting immunotherapy (such as an antigen binding protein therapy).

[0027] The invention also provides a method of preventing or reducing the progression of cancer cells expressing a TP53 mutation, the method comprising administering to a subject in need thereof, a STING agonist, thereby preventing or reducing the progression of cancer cells expressing a TP53 mutation. Preferably, the method further comprises administering a TP53-targeted therapy, such as a TP53-targeted vaccine therapy.

[0028] The invention also provides a method of preventing or reducing the progression of cancer cells expressing TP53-wildtype, the method comprising administering to a subject in need thereof, a STING agonist, thereby preventing or reducing the progression of cancer cells expressing a TP53 mutation. Preferably, the method further comprises administering a TP53-targeted therapy, such as a TP53-targeted vaccine therapy.

[0029] In any embodiment of any aspect herein, the immunotherapy, or therapy for use in combination with a STING agonist, is not a BH3-mimetic (eg is preferably not Venetoclax).

[0030] According to a further aspect of the present invention, there is provided a method of treating or inhibiting progression of a cancer in a subject, comprising: identifying the subject as a candidate for TP53-targeting therapy; identifying the cancer as comprising cells expressing STING protein; and administering to the subject both a TP53-targeting therapy and a STING agonist, wherein the STING agonist is administered sequentially or simultaneously with the TP53-targeting therapy. The method may comprise administering to the subject a synergistic combination of both a TP53-targeting drug therapy and a STING agonist.

[0031] According to a further aspect of the present invention, there is provided a method of treating or inhibiting progression of cancer in a subject having received (or where the subject is receiving) TP53-targeting therapy, the method comprising1006167084administering to the subject a STING agonist. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject having received (or where the subject is receiving) TP53-targeting therapy, the method comprising administering to the subject a STING agonist, wherein the cancer comprises cells expressing STING protein. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject having received (or where the subject is receiving) TP53-targeting therapy, comprising administering to the subject a synergistic amount of a STING agonist, such that the STING agonist and the TP53-targeting therapy provide a synergistic combination. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject having received (or where the subject is receiving) TP53-targeting therapy, comprising administering to the subject a STING agonist, wherein the cancer comprises cells expressing STING protein. In one embodiment, there is provided a method of treating or inhibiting progression of cancer in a subject having received (or where the subject is receiving) TP53-targeting therapy, comprising administering to the subject a synergistic amount of a STING agonist to provide a synergistic combination of the TP53-targeting therapy and the STING agonist, wherein the cancer comprises cells expressing STING protein.

[0032] The following features may be used in conjunction with any one of the above aspects either alone or in any suitable combination.

[0033] In any embodiment or aspect herein, the TP53-targeting therapy may be administered orally or intravenously. The STING agonist may be administered intravenously or intratumorally, typically intravenously.

[0034] In some embodiments, the STING agonist is a compound of formula (I):wherein:W is O or NH;R1is selected from:1006167084H;C3-6 cycloalkyl;C3-7 heterocyclyl optionally substituted with a group selected from: methyl; and ester; and linear or branched Ci-4alkyl optionally substituted with a group selected from: alkoxy; amino; amido; acylamido; acyl oxy; alkyl carboxyl ester; alkyl carbamoyl; alkyl carbamoyl ester; phenyl; phosphonate ester;C3-7 heterocyclyl optionally substituted with a group selected from methyl and oxo; and a naturally occurring amino acid, optionally N- substituted with a group selected from methyl, acetyl and boc;A1is CRAor N;A2is CRBor N;A3is CRcor N;1006167084A4is CRDor N; where no more than two of A1, A2, A3, and A4may be N; one or two of RA, RB, Rcand RD, (if present) are selected from H, F, Cl, Br, Me, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CF Me and OH; the remainder of RA, RB, Rcand RD, (if present) are H;Y is O, NH or CH2;RYis selected from:(a)wherein Z1is CRZ1or N;Z2is CRZ2or N;Z4is CRZ4or N;Z5 is CRZ5or N; where no more than two of Z1, Z2, Z4and Z5may be N; one or two of RZ1, RZ2, RZ4and RZ5, (if present) are selected from H, F, Cl, Br, Me, OMe, cyano, CF3, CH2OH, CH20Me, C2-4 alkenyl, and Cs heterocyclyl; the remainder of RZ1, RZ2, RZ4and RZ5, (if present) are H;(b)where R12is selected from H, F, Cl, Br, OMe, cyano and CF3;1006167084with the proviso that when A1is CF; A2, A3and A4are CH; Y is 0 or NH; RYis RYA, where Z1, Z2, Z4and Z5are CH; R1is not Et; and when A1is CF; A2, A3and A4are CH; Y is NH; RYis RYA, where Z1and Z5are CH, one of Z2and Z4is CF, and the other of Z2and Z4is CH; R1is not Et.

[0035] In some embodiments, the STING agonist is a compound of formula (II):wherein;W1is 0 or NH;R2is selected from: i. H; ii. C3-6 cycloalkyl; iii. C3-7 heterocyclyl optionally substituted with a group selected from: methyl; and ester; and iv. linear or branched C1-4 alkyl optionally substituted with a group selected from: alkoxy; amino; amido; acylamido;1006167084acyl oxy; alkyl carboxyl ester; alkyl carbamoyl; alkyl carbamoyl ester; phenyl; phosphonate ester;C3-7 heterocyclyl optionally substituted with a group selected from methyl and oxo; and a naturally occurring amino acid, optionally N- substituted with a group selected from methyl, acetyl and boc;A5is CREor N;A6is CRFor N;A7is CRGor N;A8is CRHor N; where no more than two of A5, A6, A7, and A8may be N; one or two of RA, RB, Rcand RD, (if present) are selected from H, F, Cl, Br, Me, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CF Me and OH; the remainder of RE, RF, RGand RH, (if present) are H;RN1is H or Me; one of RC2and RC3is C(=O)NH2; the other is selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CH20Me, C2-4 alkenyl and Cs heterocyclyl;RC1, and RC4are independently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CH20Me, C2-4 alkenyl and Cs heterocyclyl.

[0036] In some embodiments, the STING agonist is a compound of formula (III);1006167084wherein:Y is (CH2)n, where n is from 2 to 4;W2and W3are independently selected from OH and ORP, where Rpis Me or Et;A11is CR1or N;A12is CRJor N;A13is CRKor N;A14is CRLor N; where no more than two of A11, A12, A13, and A14may be N; one or two of R1, RJ, RKand RL, (if present) are selected from H, F, Cl, B r, Me, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CH20Me and OH; the remainder of R1, RJ, RKand RL, (if present) are H;A21is CRIAor N;A22is CRJBor N;A23is CRKCor N;A24is CRLDor N; where no more than two of A21, A22, A23and A24may be N; one or two of RIA, RJB, RKCand RLD, (if present) are selected from H, F, Cl, Br, Me, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CH20Me and OH;1006167084the remainder of RIA, RJB, RKCand RLD, (if present) are H;Res RC6ANC| RC?areindependently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CFWMe, C2-4 alkenyl and Cs heterocyclyl;Rd5, Rewanc| RC17areindependently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CFWMe, C2 -4 alkenyl and Cs heterocyclyl.

[0037] In some embodiments, the STING agonist is a compound of formula (IV)wherein:Y is either (CH2)n, where n is from 2 to 4, or -CH2-CH=CH-CH2-;R1 aand R11 aare independently selected from the group consisting of: -C(=O)OH, -C(=O)ORP1,Br, F, tetrazolyl, oxo-oxadiazolyl and(2H-triazol-4-yl), -S(=O)2OH, -P(=O)(OH)2, Br, F, tetrazolyl, oxo-oxadiazolyl,(4H-triazol-3-yl),(2H-triazol-4-yl), oxo-thiadiazolyl, thio-thiadiazolyl, thio-oxadiazolyl, hydroxy- oxadiazolyl, hydroxy-thiadiazolyl, thiohydroxy-oxadiazolyl, thiohydroxy-thiadiazolyl, -C(CRaRbRc)(CRxRyRz)XH, hydroxy-oxazolyl, thiohydroxy- oxazolyl, hydroxy-diazolyl, hydroxy-thiazolyl, thiohydroxy-thiazolyl;RP1is selected from methyl, ethyl; each Ra, Rb, Rc, Rx, Ryand Rzis independently selected from H and F;1006167084X is selected from 0 and S;A31is CRA1or N;A32is CRB1or N;A33is CRc1or N;A34is CRD1or N; where no more than two of A31, A32, A33, and A34may be N; one, two or three of RA1, RB1, RC1and RD1, (if present) are selected from H, F, Cl, Br, I, Me, Et, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CFhOMe and OH; the remainder of RA1, RB1, RC1and RD1, (if present) are H;A41is CRA2or N;A42is CRB2or N;A43is CRC2or N;A44is CRD2or N; where no more than two of A41, A42, A43and A44may be N; one, two or three of RA2, RB2, RC2and RD2, (if present) are selected from H, F, Cl, Br, I, Me, Et, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CH20Me and OH; the remainder of RA2, RB2, RC2and RD2, (if present) are H;Rc1 a, RC3aand RC4aare independently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CH20Me, C2-4 alkenyl and Cs heterocyclyl;Rc11a, Rc13aanc| Rci4aareindependently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CH20Me, C2 -4 alkenyl and Cs heterocyclyl.

[0038] In some embodiments, the STING agonists are compounds according to formula (V):1006167084wherein:Z is a 3-6 atom linker comprising 1 -6 -CH2- moieties and 0, 1 or 2 moieties independently selected from 0, NH and -NHC(O)-;Y1is H and Y11is H, or Y1and Y11together form (CH2)n, where n is 2 or 3, or -CH2- CH=CH-CH2-;R1and R11are independently selected from -C(=O)OH, a carboxylic acid bioisostere, Br and F;A1is CRAor N;A2is CRBor N;A4is CRDor N; where no more than two of A1, A2and A4may be N;RA, RBand RD, (if present) are independently selected from H, F, Cl, Br, I, Me, Et, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CFhOMe and OH;A11is CRAAor N;A13is CRccor N;A14is CRDDor N; where no more than two of A11, A13and A14may be N;1006167084RAA, RCCand RDD(if present) are independently selected from H, F, Cl, Br, I, Me, Et, CF3, cyclopropyl, cyano, OMe, OEt, CH2OH, CF Me and OH;RC1, RC3and RC4are independently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CH20Me, C2-4 alkenyl and Cs heterocyclyl;Ren, RC13and RC14are independently selected from H, Cl, F, Br, Me, OMe, OEt, cyano, CF3, CH2OH, CH20Me, C2 -4 alkenyl and Cs heterocyclyl.

[0039] Compounds described herein, including compounds of formulas (l)-(V), may be provided in the form of a pharmaceutically acceptable salt, solvate, prodrug, isomer, tautomer, polymorph and / or N-oxide thereof.

[0040] In any of the methods described herein the STING agonist may be administered in any effective amount. The effective amount may be any amount that elicits a desirable physiological response, including but not limited to when used in combination with a TP53-targeting therapy. The amount may vary based on a number of factors including the severity of disease and characteristics of the subject (including height, weight, sex, history, etc) as are typically adjusted for when determining a dose of a pharmaceutical ingredient. In some embodiments, the method may comprise administering the STING agonist in an amount of from about 10 pg / week to about 6,400 pg / week across from 1 dose every 3 weeks to 1 to 3 doses per week. In embodiments, the methods comprise administering a single dose of STING agonist.

[0041] The cancer may comprise TP53-wildtype and TP53-mutant / deficient cells. The co-administering may comprise administering the TP53-targeting therapy and the STING agonist simultaneously or may comprise administering TP53-targeting therapy and the STING agonist sequentially. Preferably the TP53-targeting therapy is administered after the STING agonist. For example, the TP53-targeting therapy may be administered from about 12 hours, about 18 hours, about 24 hours, about 36 hours or about 48 hours after administration of the STING agonist.

[0042] The cancer may be a blood cancer. The blood cancer may be selected from leukaemia, such as acute myeloid leukaemia (AML), lymphoma such as T cell lymphoma and multiple myeloma (MM), or a relapsed / refractory form of any one of these. The blood cancer may be selected from acute myeloid leukaemia (AML), T cell lymphoma and multiple myeloma (MM), or a relapsed / refractory form of any one of1006167084these. The blood cancer may be selected from acute myeloid leukaemia (AML), Natural Killer / T cell lymphoma (NKTL), extra nodal NK / T cell lymphoma (ENKTL), and multiple myeloma (MM), or a relapsed / refractory form of any one of these. The cancer may be a leukaemia selected from acute myeloid leukaemia (AML), including promyelocytic leukaemia, chronic myelogenous leukaemia (CML), and acute lymphoblastic leukaemia (ALL), or a relapsed / refractory form of any one of these. The cancer may be a lymphoma. The cancer may be a non-Hodgkin's lymphoma (NHL), such as selected from adult T cell lymphoma, lymphoblastic lymphoma, peripheral T cell lymphoma, follicular lymphoma, chronic lymphocytic leukemia / small lymphocytic lymphoma, Natural Killer / T cell lymphoma (NKTL), extra nodal NK / T cell lymphoma (ENKTL), marginal zone lymphoma, Waldenstrom's macroglobulinaemia, and mantle cell lymphoma, or a relapsed / refractory form of any one of these. The cancer may be a solid cancer. The solid cancer may be selected from small cell lung cancer, non-small cell lung cancer, squamous cell carcinoma, melanoma, breast cancer, ovarian cancer, neuroblastoma, prostate cancer, and colorectal cancer.

[0043] The subject may be a mammal, such as a human.

[0044] According to a further aspect of the present invention, there is provided a combination for treating or inhibiting progression of cancer, comprising: an anti-cancer immunotherapy and a STING agonist. In one embodiment, there is provided a combination for treating or inhibiting progression of cancer, comprising: an anti-cancer immunotherapy and a STING agonist, wherein the cancer comprises cells expressing STING protein. The combination may be a synergistic combination.

[0045] According to a further aspect of the present invention, there is provided a combination for treating or inhibiting progression of cancer, comprising: a TP53- targeting therapy and a STING agonist. In one embodiment, there is provided a combination for treating or inhibiting progression of cancer, comprising: a TP53- targeting therapy and a STING agonist, wherein the cancer comprises cells expressing STING protein. The combination may be a synergistic combination.

[0046] The combination may be in the form of a pharmaceutical composition. The anticancer immunotherapy or TP53-targeting therapy and the STING agonist may be separate preparations. The anti-cancer immunotherapy or TP53-targeting therapy and the STING agonist may be for simultaneous administration. The anti-cancer1006167084immunotherapy or TP53-targeting therapy and the STING agonist may be for sequential administration. In any embodiment, the anti-cancer immunotherapy or TP53-targeting therapy may be selected from a vaccine including an mRNA vaccine, peptide vaccine, viral vaccine (such as recombinant adenovirus or vaccinia Ankara) or dendritic cell based vaccine that targets p53. Various p53-targeting vaccines are known in the art, and are described, for example in Zhou et al., (2021) Frontiers in Cell and Developmental Biology, 9:762796, incorporated herein by reference. The anti-cancer immunotherapy or TP53 targeting therapy may comprise an antigen binding protein therapy. The TP53-targeting antigen binding protein therapy may be any therapy including an antigen binding protein for targeting / binding to TP53. In non-limiting examples, the therapy may comprise an antibody, or a cell-based therapy comprising an antigen binding domain (such as CAR-T therapy). The antibody therapy may comprise a bispecific antibody or antigen binding fragment thereof, such as a bispecific T cell engager molecule. In one non-limiting example, the bispecific antibody is as described in Hsiue et al., (2021 ), Science, 371 : 6533, incorporated herein by reference.

[0047] The anti-cancer immunotherapy may be any suitable immunotherapy for treating cancer, but will be understood to typically be a therapy that requires presentation of HLA: peptide complexes to elicit a therapeutic effect.

[0048] Optionally, the immunotherapy may comprise an immune checkpoint inhibitor (such as an anti-PD-1 , an anti-PD-L1 or an anti-CTLA4 antibody), or may be an immunomodulator. The immunotherapy may comprise an antigen binding protein for binding to immune cells. For example, the immunotherapy may comprise a bispecific T- cell engager molecule.

[0049] The immunotherapy may comprise a genetically modified immune cell, such as a genetically modified T, NKT cell or the like. Optionally, the immunotherapy comprises a CAR-T cell.

[0050] Further still, the immunotherapy may comprise a dendritic cell-based therapy.

[0051] In any embodiment, the STING agonist may be selected from a non-nucleotide small molecule, such as MSA-2, a non-cyclic dinucleotide, such as diABZI STING Agonist 1 , and a synthetic cyclic dinucleotide, such as ADU-S100 / MIW815. The STING agonist may be selected from MSA-2, diABZI STING Agonist 1 , and ADU-1006167084S100 / MIW815. In any embodiment, the STING agonist may be a compound of any of formulas (I) to (V).

[0052] The cancer may comprise cells expressing STING protein. The cancer may comprise TP53-wildtype and TP53-mutant cells.

[0053] According to a further aspect of the present invention, there is provided use of a TP53-targeting therapy and a STING agonist in the manufacture of a medicament for the treatment of cancer in a subject, wherein the TP53-targeting therapy (eg TP53- targeting vaccine) and a STING agonist are for co-administration. The coadministration may be sequential or simultaneous administration.

[0054] Further still there is provided use of a STING agonist in the manufacture of a first medicament; and a TP53-targeting therapy in the manufacture of a second medicament, wherein the medicaments are for the treatment of cancer in a subject. Optionally, the medicaments are for co-administration. The co-administration may be sequential or simultaneous administration.

[0055] According to a further aspect of the present invention, there is provided a use of a STING agonist in the manufacture of a medicament for conjoint administration with a TP53-targeting therapy for the treatment of cancer in a subject. The conjoint administration may be sequential or simultaneous administration

[0056] According to a further aspect of the present invention, there is provided use of a TP53-targeting therapy in the manufacture of a medicament for conjoint administration with a STING agonist for the treatment of cancer in a subject. The conjoint administration may be sequential or simultaneous administration

[0057] According to a further aspect of the present invention, there is provided a kit comprising in separate parts:• a TP53-targeting therapy• a STING agonist• and optionally instructions for the use of a combination of the TP53-targeting therapy (such as TP53-targeting vaccine) and STING agonist, for example, in any of the methods described herein.1006167084

[0058] According to a further aspect of the present invention, there is provided a kit comprising in separate parts:• a TP53-targeting therapy• and instructions for the conjoint use of a TP53-targeting therapy with a STING agonist, for example, in any of the methods described herein.

[0059] According to another aspect of the present invention, there is provided a kit comprising in separate parts:• a STING agonist; and• instructions for the conjoint use of the STING agonist with a TP53-targeting therapy for example, in any of the methods described herein.

[0060] As used herein, except where the context requires otherwise, the term "comprise" and variations of the term, such as "comprising", "comprises" and "comprised", are not intended to exclude further additives, components, integers or steps.

[0061] Further aspects of the present invention and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, given by way of example and with reference to the accompanying drawings.Brief description of the drawings

[0062] Figure 1 : Decreased expression of MHO class I and II in TP53 KO cells relative to WT. (A) Volcano plots of MV411 and MOLM13 cell lines highlighting differential expression of MHC molecules comparing WT to TP53 KO cells as determined by surface proteomics. (B) Volcano plots of comparative RNA analysis of TP53 WT and KO MOLM13 and MV411 cells showing minimal differential regulation of genes associated with MHC peptide processing and presentation.

[0063] Figure 2: Generation of cell lines expressing the 4 most common TP53 mutations in AML. (Left) Lollipop plot generated from AML patients with TP53 mutations highlighting the four most common mutations at residues R175, Y220, R248 and R273. (Right) Schematic diagram depicting the process of generating cell lines1006167084expressing these 4 mutants; TP53 KO cell lines of MV411 and M0LM13 AML lines (WT for TP53) were generated by CRISPR and the 4 mutant TP53 variants were overexpressed in these cells using lentivirus, generating stably expressing TP53 mutants with fluorescent proteins labelled for cell tracking.

[0064] Figure 3: Expression of MHC in TP53 mutant cell lines relative to WT. (A) Representative FACS plots showing decreased expression of HLA-ABC and HLA_DR / DP / DQ on TP53 mutant cell lines relative to the empty vector control with WT TP53. (B) Volcano plots of decreased HLA ABC expression in TP53 mutant cell lines (R175H, Y220C, R248W and R273H) when compared to WT as determined by surface proteomics. (C) Plots of Log2 expression of HLA-A, B and C across MOLM13 and MV41 1 WT, TP53 KO and mutant cell lines as measured by global proteomics showing non-significant differences. Box plots show mean and standard deviation of data.

[0065] Figures 4A and 4B: STING agonists can increase HLA expression in cell lines irrespective of TP53 status. ACU-2086 (A) and ACU-0514 (B) were able to increase expression of HLA Class I (ABC) molecules on cell surface in a dosedependent manner following 24 hours of continuous exposure.

[0066] Figure 4C: MHC class I gene expression increases with STING agonist treatment. MOLM13 cell lines (WT, STING KO, TP53 KO, and R175H, Y220C, R248W, and R273H mutants) were treated with 10 nM STING agonist or DMSO control for 24 hours. Each column represents a single replicate.

[0067] Figure 4D: Global protein expression of HLAs and B2M increase with STING agonist treatment. Plots of Log2 Expression of HLA-A, B and C and B2M in MOLM1 3 cell lines either WT or STING KO were treated with STING agonist for 24 hours. Global proteomics revealed an increase in HLA and B2M following DiABZI STING agonist treatment. Error bars are standard deviation (SD).

[0068] Figure 5: STING agonist ACU-0943 can increase HLA expression in AML cell lines following 30-minute drug exposure. Increased HLA Class I (ABC) expression can be seen from as little as 4 hours and up to 48 hours following a 30-minute exposure to ACU-0943 in the TP53 mutant cells (R175H, Y220C, R248W and R273H).

[0069] Figure 6: Interferons alpha, gamma and STING agonists increase HLA expression in AML cell lines. Representative FACS plots from MOLM13 R175H show1006167084that cytotoxic drugs such as daunorubicin, Venetoclax and a DNMTI i do not increase HLA expression in the same manner as interferons alpha, gamma and STING agonist ACU-0514.

[0070] Figure 7: High doses of STING agonists are able to kill TP53 mutant AML cells via apoptosis. Dose-titrations of ACU-0514 and ACU-2086 highlight that high concentrations of both compounds can trigger cell death in a robust manner.

[0071] Figure 8: HLA increase is not dependent on cell death. Using cells unable to undergo cell death, there is a robust increase in HLA class I (ABC) expression following 24-hour exposure to ACU-0943 at even low doses.

[0072] Figure 9: HLA Class I (ABC) expression is reduced in blasts from patients with TP53 mutations relative to those with WT TP53. A) FACS plots of HLA class I (ABC) and II (DR DP DQ) expression on patient blasts show reduced expression of class I in those with TP53 mutations. B) FACS plots of HLA class I (ABC) and II (DR DP DQ) expression in blasts, monocytes and lymphocytes in all patient samples showing no correlation between TP53 status and HLA expression on lymphocytes and monocytes. C) FACS plots of Class I (HLA-ABC) and class II (HLA-DR DP DQ) on blasts from 14 patients with AML WT for TP53 and 18 patients with TP53 mutated AML. Both MHC class I and class II had significantly lower MFI on patient samples with TP53 mutations. Error bars are SD. * indicates data is statistically significant (unpaired T-test).

[0073] Figure 10: STING agonist ACU-0943 increases HLA class I expression on TP53 mutated AML blasts. A) FACS plots of HLA class I (ABC) expression on patient blasts with WT TP53 and one normal peripheral blood sample highlighting little to no change in HLA expression with exposure to ACU-0943. B) FACS plots of HLA class I (ABC) expression on patient blasts with mutant TP53 highlighting ability to increase HLA expression with exposure to ACU-0943.

[0074] Figure 11 : STING expression in primary human samples measured using intracellular flow cytometry. X-axis shows the lineage of cells and y axis shows STING expression normalised to a cell line control. STING expression, normalized to cell line positive control, in different normal and malignant primary haematopoietic cells. Data shown- 63 independent primary PB or BM samples (41 AML / MDS-IB and 221006167084normal). Comparison between groups was made using one-way ANOVA with Tukey’s multiple comparison test; **=p<0.01 , ***=p<0.001 , ****=p<0.0001 .

[0075] Figure 12: A single dose of STING agonist ACU-0943 can increase HLA expression. (A) Schematic diagram of experimental set up. (B) representative HLA- ABC fluorescence intensity by histogram of 2 mice at each time point. (C) The fold change of HLA-ABC median fluorescence intensity from first measurement at 24 hours to second measurement at 48 hours. Error bars are SD. * indicates data is statistically significant (unpaired T-test).Detailed description of the embodiments

[0076] Treatment and prevention of cancers expressing the mutant forms of the tumour suppressor gene, TP53, remain a major clinical challenge for treatment of cancer. TP53 is the most commonly mutated gene across all cancer types, but TP53 mutant cancers are particularly resistant to cytotoxic drugs that depend on causing DNA damage to trigger cancer cell death.

[0077] While various treatments that specifically target mutant forms of TP53 have been developed, the present inventors have identified a causal link between immunoevasion and TP53 mutation. The inventors have shown that there is a link between TP53 status and HLA class I (ABC) expression on the surface of cells and that TP53 mutations thereby promote immunoevasion via suppression of HLA expression. HLA class I molecules present antigens to the immune system, allowing them to be recognised as defective, targeting these cells for destruction. Downregulation of HLAs is a mechanism by which cancer cells can evade the immune system which is a hallmark of cancer. Unfortunately, immune based therapies have traditionally had poor efficacy in AML, however the inventors believe the combination of STING agonists with these immune based therapies may increase therapeutic potential in cancers, including in AML.

[0078] Here the inventors have shown that STING agonists can increase the expression of HLA class I molecules on the surface of AML cells, and particularly in TP53 mutated AML, there is a robust restoration of HLA expression upon exposure to STING agonists.1006167084

[0079] Thus, the inventors have identified a new approach for the treatment of cancers, in particular cancers expressing mutated TP53.Definitions

[0080] C3-6 Cycloalkyl: The term “C3-6 cycloalkyl” as used herein, pertains to a monovalent moiety obtained by removing a hydrogen atom from a carbon atom of a saturated cyclic hydrocarbon compound having from 3 to 6 carbon atoms. Examples of C3-6 cycloalkyl groups include, but are not limited to, cyclopropyl (C3), cyclobutyl (C4), cyclopentyl (Cs) and cyclohexyl (Ce).

[0081] C3-7 Heterocyclyl: The term “C3-7 heterocyclyl” as used herein, pertains to a monovalent moiety obtained by removing a hydrogen atom from a ring atom of a monocyclic heterocyclic compound, which moiety has from 3 to 7 ring atoms; of which from 1 to 2 atoms are heteroatoms, chosen from oxygen, sulfur or nitrogen. The C3-7 heterocyclyl groups may be non-aromatic or aromatic ring systems. Aromatic C3-7 heterocyclyl groups may be referred to as C3-7 heteroaryl groups.

[0082] In this context, the prefixes (e.g. C3-7) denote the number of ring atoms, or range of number of ring atoms, whether carbon atoms or heteroatoms. Thus a prefix may in some instances be interchanged with an alternative prefix defining the number of ring member atoms, for example the prefix “C3-7” may be interchanged with the prefix “3- to 7-membered”. In some embodiments, the C3-7 heterocyclyl moieties in the compounds of the invention may be C3, C4, Cs, Ce or C7 heterocyclyls or any combination of these different sized rings / ring systems, such as C3-6, C4-7 or C5-6 heterocyclyl groups.

[0083] Examples of C3-7 heterocyclyl groups include, but are not limited to, those derived from:N1: aziridine (C3), azetidine (C4), pyrrolidine (tetrahydropyrrole) (Cs), pyrroline (e.g., 3-pyrroline, 2,5-dihydropyrrole) (Cs), 2H-pyrrole or 3H-pyrrole (isopyrrole, isoazole) (Cs), pyrrole (Cs), piperidine (Ce), dihydropyridine (Ce), tetrahydropyridine (Ce), pyridine (Ce), azepine (C7), azepane (C7);N2: diazirine (C3) diazetidine (C4), imidazolidine (Cs), pyrazolidine (diazolidine) (Cs), imidazoline (Cs), pyrazoline (dihydropyrazole) (Cs), imidazole (Cs),1006167084pyrazole (Cs), piperazine (Ce), pyrazine (Ce), pyrimidine (Ce), pyridazine (Ce), diazepine (C7), diazepane (C7);O1: oxetane (C4), tetrahydrofuran (Cs); oxane (Ce);O2: dioxetane (C4), dioxolane (Cs); dioxane (Ce), dioxole (Cs);N1O1: tetrahydrooxazole (Cs), di hydrooxazole (Cs), tetrahydroisoxazole (Cs), dihydroisoxazole (Cs), isoxazole (Cs), oxazole (Cs), morpholine (Ce), tetrahydrooxazine (Ce), dihydrooxazine (Ce), oxazine (Ce);Si: thiirane (C3), thietane (C4), thiolane (tetrahydrothiophene) (Cs), thiphene (Cs), thiane (tetrahydrothiopyran) (Ce), thiepane (C7);N1S1: thiazoline (Cs), thiazolidine (Cs), thiazole (Cs), isothiazole (Cs), thiomorpholine (Ce), thiazine (Ce);O1S1: oxathiolidene (Cs), isoxthiolidine (Cs), oxathiole (Cs), isoxathiole (Cs) and oxathiane (thioxane) (Ce);N2O: oxadiazole (Cs);N2S: thiadiazole (Cs).

[0084] C1-4 Alkyl: The term “C1-4 alkyl” as used herein, pertains to a monovalent moiety obtained by removing a hydrogen atom from a carbon atom of a saturated hydrocarbon compound having from 1 to 4 carbon atoms.

[0085] Examples of saturated alkyl groups include, but are not limited to, Me: methyl (Ci), Et: ethyl (C2), Pr: propyl (C3), and Bu: butyl (C4).

[0086] Examples of saturated linear alkyl groups include, but are not limited to, methyl (Ci), ethyl (C2), nPr: n-propyl (C3), and nBu: n-butyl (C4).

[0087] Examples of saturated branched alkyl groups include, but are not limited to, iPr: iso-propyl (C3, -C(CH3)2), iBu: / so-butyl (C4), sBu: sec-butyl (C4) and tBu: fe / t-butyl (C4).

[0088] C2-4 Alkenyl: The term “C2-4 alkenyl” as used herein, pertains to an alkyl group having from 2 to 4 carbon atoms and having one or more carbon-carbon double bonds.1006167084

[0089] Examples of unsaturated alkenyl groups include, but are not limited to, ethenyl (vinyl, -CH=CH2), 1 -propenyl (-CH=CH-CH3), 2-propenyl (allyl, -CH-CH=CH2), isopropenyl (1-methylvinyl, -C(CH3)=CH2) and butenyl (C4).

[0090] C1-4 fluoroalkyl: The term “C1-4 fluoroalkyl” as used herein, pertains to a Ci-4alkyl group, substituted with one or more fluorine atoms.

[0091] Alkoxy: -OR wherein R is a C1-4 alkyl group as defined above. It can be represented as -O-C1-4 alkyl. Examples of alkoxy groups include, but are not limited to, methoxy (OMe, Ci), ethoxy (OEt, C2), propyloxy (C3), and butyloxy (C4).

[0092] Alkyl carbamoyl: -NHC(=O)OR wherein R is a C1-4 alkyl group as defined above. Examples of alkyl carbamoyl groups include, but are not limited to, -N(H)C(=O)OCH3, - N(H)C(=O)OCH2CH3, and -N(H)C(=O)OC(CH3)3.

[0093] Alkyl carbamoyl ester: -OC(=O)NRR’ wherein R and R’ are independently selected from H and C1-4 alkyl as defined above. Examples of alkyl carbamoyl ester groups include, but are not limited to, -OC(=O)N(CH3)2, and -OC(=O)N(H)CH3.

[0094] Alkyl carboxyl ester: -OC(=O)OR wherein R is a C1-4 alkyl group as defined above. Examples of alkyl carboxyl ester groups include, but are not limited to, -OC(=O)OCH3, -OC(=O)OCH2CH3, -OC(=O)OC(CH3)3, and -OC(=O)OCH(CH3)2.

[0095] Amino: -N(R)R’ wherein R and R’ are independently selected from H and C1-4 alkyl as defined above. Examples of an amino group include, but are not limited to, - NH2, -N(H)CH3, -N(H)C(CH3)2, -N(CH3)2, -N(CH2CH3)2.

[0096] Amido (carbamoyl, carbamyl, aminocarbonyl, carboxamide, aminoacyl): -C(=O)N(R)R’ wherein R and R’ are independently selected from H and C1-4 alkyl as defined above. Examples of an amido group include, but are not limited to, C(=O)NH2, -C(=O)N(H)CH3, -C(=O)N(CH3)2, -C(=O)N(H)CH2CH3, and -C(=O)N(CH2CH3)2.

[0097] Acylamido: -N(R)C(=O)R’ wherein R and R’ are independently selected from H and C1-4 alkyl as defined above. Examples of an acylamido group include, but are not limited to, -N(H)C(=O)CH2CH3, -N(H)C(=O)CH3and -N(CH3)C(=O)CH3.1006167084

[0098] Phenyl: -CeHs, wherein the phenyl may itself be optionally substituted by one or more Ci-4alkyl groups, one or more C1-4 fluoroalkyl groups, one or more C1-4 alkoxy groups, one or more halo substituents and one or more cyano substituents.

[0099] Benzyl: -CH2-phenyl, wherein phenyl is as defined above.

[0100] Ester (carboxylate, carboxylic acid ester, oxycarbonyl): -C(=O)OR, wherein R is an ester substituent, for example, a C1-4 alkyl group, a C3-7 heterocyclyl group, or a phenyl group, as defined above, preferably a C1-4 alkyl group. Examples of ester groups include, but are not limited to, -C(=O)OCH3, -C(=O)OCH2CH3, -C(=O)OC(CH3)3, and - C(=O)OPh.

[0101] Acyloxy (reverse ester): -OC(=O)R, wherein R is an acyloxy substituent, for example, a Ci-4alkyl group, a C3-7 heterocyclyl group, or a phenyl group, as defined above, preferably a Ci-4alkyl group. Examples of acyloxy groups include, but are not limited to, -OC(=O)CH3(acetoxy), -OC(=O)CH2CH3, -OC(=O)C(CH3)3and -OC(=O)Ph. Further examples of acyloxy groups include, but are not limited to, methylester (Ci), ethylester (C2), propylester (C3) and butylester (C4).

[0102] Naturally occurring amino acid: The term “a naturally occurring amino acid”, as used herein, pertains to a monovalent moiety obtained by removing a hydrogen atom from a carboxyl group or an amino group on one of the amino acid compounds found commonly in nature (for example, alanine, arginine, asparagine, aspartate, cysteine, glycine, glutamine, glutamate, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine). The amino acid is particularly selected from isoleucine, leucine and valine, most particularly valine.

[0103] In each of these groups the carbon atom which is bonded to both a carboxyl and an amino group is known as the a carbon and the carboxyl and amino groups to which it is attached are the a-carboxyl and a-amino groups. Naturally occurring amino acids are optionally substituted with a protecting group on the a-amino group or any other amino group on the moiety, protecting groups include but are not limited to acetyl, methyl, fluorenylmethoxycarbonyl (Fmoc), carboxybenzyl (Cbz; benzyloxycarbonyl), phthalimido and tertbutyl carbamate (boc) groups.1006167084

[0104] Phosphonate ester: -P(O)(OR)OR’, wherein R and R’ are independently selected from Ci-4alkyl as defined above. Examples of a phosphonate ester include, but are not limited to -P(O)(OEt)2.

[0105] Cyano: -C^N.

[0106] Pivaloyloxymethyl: A group of formula

[0108] Oxo-thiadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, a sulfur ring atom, and an oxo substituent. Examples of oxo-thiadiazolyl groups include:2-oxo-3H-1 -th ia-3, 4-diazol-5-y I 2-oxo-3H-1 -th ia-3, 5-d iazol-4-y I

[0109] Thio-thiadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, a sufur ring atom, and a thiocarbonyl substituent. Examples of thio-thiadiazolyl groups include:2-thio-3H-1-thia-3,4-diazol-5-yl 2-thio-3H-1-thia-3,5-diazol-4-yl

[0110] Thio-oxadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, an oxygen ring atom, and a thiocarbonyl substituent. Examples of thio- oxadiazolyl groups include:10061670842-th io-3H-1 -oxa-3,4-diazol-5-yl 2-thio-3H-1 -oxa-3,5-diazol-4-yl

[0111] Hydroxy-thiadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, a sufur ring atom, and a hydroxy substituent. These groups may be tautomeric with corresponding oxo-thiadiazolyl groups under some conditions.Examples of hydroxyl-thiadiazolyl groups include:2-hydroxy-1-thia-3,4-diazol-5-yl 2-hydroxy-1-thia-3,5-diazol-4-yl

[0112] Hydroxy-oxadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, an oxygen ring atom, and a hydroxy substituent. These groups may be tautomeric with corresponding oxo-oxadiazolyl groups under some conditions.Examples of hydroxyl-oxadiazolyl groups include:2-hydroxy-1 -oxa-3,4-diazol-5-yl 2-hydroxy-1 -oxa-3,5-diazol-4-yl

[0113] Thiohydroxy-thiadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, a sufur ring atom, and a thiohydroxy substituent. These groups may be tautomeric with corresponding thio-thiadiazolyl groups under some conditions. Examples of thiohydroxyl-thiadiazolyl groups include:2-thiohydroxy-1 -thia-3,4-diazol-5-yl 2-thiohydroxy-1 -thia-3,5-diazol-4-yl

[0114] Thiohydroxy-oxadiazolyl: A 5 membered heterocyclic radical having two nitrogen ring atoms, an oxygen ring atom, and a thiohydroxy substituent. These groups may be tautomeric with corresponding thio-oxadiazolyl groups under some conditions.Examples of thiohydroxyl-oxadiazolyl groups include:10061670842-thiohydroxy-1 -oxa-3,4-diazol-5-yl 2-thiohydroxy-1 -oxa-3,5-diazol-4-yl

[0115] Hydroxy-oxazolyl: A 5-membered heterocyclic radical having a nitrogen ring atom, an oxygen ring atom, and a hydroxy substitutuent. Examples of hydroxyl-oxazolyl groups include:3-hydroxy-1 -ox-2-azol-5-yl 4-hydroxy-1 -ox-2-azol-5-yl

[0116] In some embodiments, the hydroxyl-oxazolyl may be a 3-hydroxy-1 -ox-2-azol-5- yi.

[0117] Thiohydroxy-oxazolyl: A 5-membered heterocyclic radical having a nitrogen ring atom, an oxygen ring atom and a thiohydroxy substituent. Examples of thiohydroxy- oxazolyl groups include:3-thiohydroxy-1 -ox-2-azol-5-yl 4-thiohydroxy-1 -ox-2-azol-5-yl

[0118] In some embodiments, the hydroxyl-oxazolyl may be a 3-thiohydroxy-1-ox-2- azol-5-yl.

[0119] Hydroxy-thiazolyl: A 5-membered heterocyclic radical having a nitrogen ring atom, a sulfur ring atom, and a hydroxy substituent. Examples of hydroxy-thiazolyl groups include:3-hydroxy-1 -thia-2-azol-5-yl 4-hydroxy-1 -thia-2-azol-5-yl

[0120] In some embodiments, the hydroxy-thiazolyl may be a 3-hydroxy-1 -thia-2-azol-5-yl.1006167084

[0121] Thiohydroxy-thiazolyl: A 5-membered heterocyclic radical having a nitrogen ring atom, a sulfur ring atom and a thiohydroxy substituent. Examples of thiohydroxy-thiazolyl groups include:3-thiohydroxy-1 -thia-2-azol-5-yl 4-thiohydroxy-1 -thia-2-azol-5-yl

[0122] In some embodiments, the hydroxyl-oxazolyl may be a 3-thiohydroxy-1-thia-2- azol-5-yl.

[0123] Hydroxy-diazolyl: A 5-membered heterocyclic radical having two nitrogen ring atoms and a hydroxy substituent. Examples of hydroxydiazolyl groups include:3-hydroxy-1 H-1 ,2-diazol-5-yl 1 -hydroxy-1 ,2-diazol-3-yl[ 4-yl: A group of formula:

[0125] Unless the context requires otherwise, where the terms “comprise”, “comprises” and “comprising” are used in the specification (including the claims) they are to be interpreted as specifying the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components, or group thereof.

[0126] It is to be further understood that terminology, such as “comprise”, or variations such as “comprises” or “comprising”, inherently include within their scope (without being limited to) versions of the invention that excludes other elements directly related to the invention. Accordingly, terminology, such as “consisting of” or “consisting essentially of”, can be substituted for terminology, such as “comprise”, “comprises” or “comprising” with the effect of limiting the scope of the invention to the specifically recited elements.1006167084Notably, where it is explicitly intended for the invention to be considered in an exhaustive manner, such limitations should be considered to relate only to the inventive concept disclosed herein and other features can be added, which fall outside of the scope of the inventive concept. Such features or elements may include, but are not limited to, excipients, formulations, additives, diluents, packaging, adjuvants and collocated features which are not to be excluded by terminology such as “consisting of” or “consisting essentially of”.STING agonists

[0127] The combinations described herein utilise a STING agonist. There are numerous STING agonists known in the art that are considered suitable for use in accordance with the present disclosure. Generally, STING agonists include small molecule nucleoside analogues, such as synthetic cyclic dinucleotides, and emerging second-generation noncyclic dinucleotides or non-nucleoside analogues.

[0128] By way of non-limiting example, suitable STING agonists may include MSA-2 (Merck; CAS No. 129425-81-6), which is a non-nucleotide small molecule STING agonist; MK-1454 (ulevostinag; Merck; CAS No. 2082743-96-0) which is a synthetic cyclic dinucleotide STING agonist being investigated for treatment of solid tumours, lymphomas, and head and neck squamous cell carcinoma; diABZI compound 3, also known as diABZI STING agonist 1 (GSK; CAS No. 2138498-18-5), which is a non-cyclic dinucleotide STING agonist; TAK-676 (dazostinag; Takeda; CAS No. 2553413-93-5), which is a synthetic cyclic dinucleotide STING agonist, ADU-S100 (also known as MIW815; Novartis; CAS No. 1638750-96-5; now withdrawn) which is a synthetic cyclic dinucleotide STING agonist investigated for activity against solid tumours and lymphomas; E7766 (CAS No. 2242635-03-4, Eisai, Inc.), which is a macrocycle-bridged STING agonist investigated for activity against solid tumours and lymphomas, MK-2118 (Merck), which is a small molecule STING agonist being investigated for activity against solid tumours and lymphomas, and SB 11285 (invoX Pharma) which is a small molecule STING agonist being investigated for activity against solid tumours, head and neck squamous cell carcinoma and melanoma), the structures of some of which are shown below:1006167084MSA-2 MK-1454 diABZI E7766

[0129] Suitable STING agonists are described in WO 2019 / 219820 (US17,054,850),WO 2021 / 009362 (US 17 / 624,137), WO 2021 / 009365 (US17 / 624134), WO 2021 / 119753 (US 17 / 786792), WO 2022 / 266711 and WO 2024 / 130341 (US19 / 140635), the entire disclosure of each of these is incorporated herein by reference. In particular, embodiments of the STING agonist compounds (I) to (V) described in these publications are incorporated herein.

[0130] Specific examples of STING agonists are given in Table 1 , below.Table 1. Examples of compounds of the present invention10061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084100616708410061670841006167084

[0131] In some embodiments, the STING agonist is a compound of formula (I). In embodiments, the STING agonist is a compound selected from any one of compounds1-1 to 1-172.

[0132] In some embodiments, the STING agonist is a compound of formula (II). In embodiments, the STING agonist is a compound selected from any one of compounds2-1 to 2-25.

[0133] In some embodiments, the STING agonist is a compound of formula (III). In embodiments, the STING agonist is a compound selected from any one of claims 3-1.1 to 3-24.

[0134] In some embodiments, the STING agonist is a compound of formula (IV). In embodiments, the STING agonist is a compound selected from any one of compounds4-1 to 4-112. In embodiments, the STING agonist is compound 4-11 or 4-46.

[0135] In some embodiments, the STING agonist is a compound of formula (V). In embodiments, the STING agonist is a compound selected any one of compounds 5-1 to5-15.

[0136] In one embodiment, the STING agonist used herein is selected from a synthetic cyclic dinucleotide, a noncyclic dinucleotide, or a non-nucleoside small molecule. In one embodiment, the STING agonist used herein is a synthetic cyclic dinucleotide. In one embodiment, the STING agonist used herein is a noncyclic dinucleotide. In one embodiment, the STING agonist used herein is a non-nucleoside small molecule.

[0137] Other STING agonist compounds, including antibody-drug conjugates comprising a STING agonist (such as any one of the aforementioned STING agonists)1006167084covalently attached to a monoclonal antibody, and dendrimer-drug conjugates comprising a STING agonist (such as any one of the aforementioned STING agonists) encapsulated within or conjugated to the surface of a dendrimer, are also envisaged to be useful in the combination therapies described herein. Accordingly, in one embodiment, the STING agonist compound used in the combinations herein comprises one or more STING agonists conjugated to a delivery component. In one embodiment, the STING agonist compound used in the combinations herein comprises a synthetic cyclic dinucleotide, a noncyclic dinucleotide, or a non-nucleoside small molecule conjugated to a delivery component. In one embodiment, the delivery component is selected from a monoclonal antibody, a ligand, and a dendrimer. In one embodiment, the delivery component is a monoclonal antibody. In one embodiment, the delivery component is a ligand, in some embodiments selected from a protein, a protein fragment, a peptide, a small molecule, and a nucleic acid. In one embodiment, the delivery component is a dendrimer. In one embodiment, the STING agonist compound used herein comprises a synthetic cyclic dinucleotide conjugated to a delivery component. In one embodiment, the STING agonist compound used herein comprises a noncyclic dinucleotide conjugated to a delivery component. In one embodiment, the STING agonist compound used herein comprises a non-nucleoside small molecule conjugated to a delivery component. In each of these embodiments, the delivery component may be selected from a monoclonal antibody, a ligand and a dendrimer. For the avoidance of doubt, any references herein to STING agonists will be understood to encompass STING agonist compounds.

[0138] It will be understood that STING agonists are useful for the treatment of a wide range of solid cancers, including but not limited to prostate cancer, squamous cell carcinoma, non-small cell lung cancer, melanoma, breast cancer, colorectal cancer, fibrosarcoma, and glioma. STING agonists are also useful for the treatment of blood cancers, including but not limited to certain lymphomas and acute myeloid leukaemia. In one embodiment, STING agonists are suitable for treatment of cancers that express STING protein. In one embodiment, STING agonists are not suitable for treatment of human B-cell lymphomas, as these malignant cells lack STING expression. In one embodiment, STING agonists are particularly suitable for treatment of malignant cells expressing STING and that carry a TP53 mutation. In one embodiment, STING agonists are suitable for treatment of malignant cells expressing STING in a TP53- independent manner. In one embodiment, the TP53-independence of STING agonists1006167084makes the combination described herein suitable for induction therapy treatment of patient groups who have in their malignant cells significant DNA damage as a result of previous radiation therapy and / or chemotherapy and that may otherwise not tolerate subsequent high-dose cancer treatment induction regimes. In one embodiment, the TP53-independence of STING agonists makes the combination described herein suitable for patient groups with high levels of TP53-mutant malignant cells, as these have a severely impaired capability to detect DNA damage and therefore initiate apoptosis through traditional innate pathways. It will be appreciated that cancers deemed treatable with a STING agonist, including those specifically mentioned in this paragraph, are candidates for the combination therapies described herein.

[0139] Any suitable pharmaceutically acceptable dose of STING agonist may be used in the combinations as described herein. STING agonists have been previously studied and used in combination immunotherapy with the aim of enhancing host anti-cancer immune responses, and therefore dosage regimes from such therapies may be useful in the present combinations and methods. By way of non-limiting example, in some indications, guidance may be taken from dosage regimes in which dosages of between 10 pg / week to about 6,400 pg / week, or between 10 pg / week to about 1 ,500 pg / week, or between 10 pg / week to about 3,000 pg / week, or between 90 pg / week to about 3,000 pg / week, are indicated for any suitable treatment period. These dosages may be suitable for intratumoral administration. In one embodiment, the STING agonist is administered once weekly. In one embodiment, the STING agonist is administered 2-3 times weekly. In one embodiment, the STING agonist is administered once every 2-3 weeks. These dosages may be administered in any suitable appropriate ramp-up schedule or any suitable on / off schedule, such as in a monthly 3 weeks on / 1 week off treatment cycle. Dosages may be continued in monthly cycles for any suitable number of cycles, such as for from 1 to 6, or 1 to 12, or 1 to 24 monthly cycles. Intravenous dosage schedules may differ from the above-listed weekly dosages. Preliminary dosing cycles for cancer treatment using STING agonists in the combinations and methods described herein may be calculated by those of skill in the art using any suitable methods.

[0140] STING agonists useful herein may be in any suitable dosage form. In one embodiment, the STING agonist is in the form of a suspension or solution for intra- tumoural administration, intravenous administration, or subcutaneous administration. In1006167084one embodiment, the STING agonist is in a form suitable for intra-tumoural administration or intravenous administration. In one embodiment, the STING agonist is in the form of a suspension or solution for intravenous administration. In one embodiment, the STING agonist is for intravenous administration. In one embodiment, the STING agonist is for intra-tumoural administration.Combinations

[0141] Disclosed herein are combinations for treating cancer to inhibit its progression, where the combinations comprise a TP53-targeted therapy or immunotherapy and a STING agonist. In one embodiment, the combination is a synergistic combination. In some embodiments, the combination is in the form of a pharmaceutical composition. The pharmaceutical composition preferably comprises separate preparations of a TP53- targeted therapy or immunotherapy and a STING agonist, especially in instances where the two drugs are indicated for different routes of administration and / or according to different dosage schedules. In certain embodiments, the combination is in the form of a kit comprising the separate preparations of a TP53-targeted therapy or immunotherapy and a STING agonist and instructions directing that the two drugs are to be used in combination treatment for the specified indications. In one embodiment, the combination comprising a TP53-targeted therapy or immunotherapy and a STING agonist comprises separate preparations of a TP53-targeted therapy or immunotherapy, such as in oral dosage form, and a STING agonist, such as in injectable form. In one embodiment, the combination comprises separate preparations of a TP53-targeted therapy or immunotherapy in oral dosage form and a STING agonist in intra-tumoural or intravenous injectable form.

[0142] In certain embodiments, the TP53-targeted therapy or immunotherapy and the STING agonist are indicated for simultaneous or sequential administration. In one embodiment, the TP53-targeted therapy or immunotherapy and the STING agonist are indicated for simultaneous administration. Simultaneous administration may include where the TP53-targeted therapy or immunotherapy is administered on a dosage program that ensures there are pharmaceutically active levels of the TP53-targeted therapy or immunotherapy in the system of the subject being treated when the STING agonist is administered. In some embodiments, the TP53-targeted therapy or immunotherapy may be administered on a daily basis, and the STING agonist may be administered on a weekly basis, and it is envisaged that the two dosage programs will1006167084overlap to ensure the subject has both drugs in their system at the same time. Simultaneous administration may include where the TP53-targeted therapy or immunotherapy and the STING agonist are administered to the subject at the same time. Accordingly, in some embodiments, the TP53-targeted therapy or immunotherapy may be administered at the same frequency as the STING agonist, such as from 1 -3 times per week, such that the dosage programs of the TP53-targeted therapy or immunotherapy and the STING agonist are the same or substantially the same.

[0143] In some embodiments, it may be appropriate for the TP53-targeted therapy or immunotherapy and the STING agonist to be administered sequentially, for example, where the TP53-targeted therapy or immunotherapy g is administered orally and a delay is required for it to reach acceptable blood plasma levels before administration of the STING agonist intravenously or intra-tumourally. In other embodiments, it is sufficient for both the TP53-targeted therapy or immunotherapy and the STING agonist to be administered at different times but within the same treatment window, such that there is not necessarily biological action of the two drugs at the same time, but there is action of the two drugs on the patient within the same treatment window.

[0144] It is also envisaged that the combinations herein could comprise one or more TP53-targeting therapies or immunotherapies and one or more STING agonists. In other embodiments, the combinations herein may further comprise one or more other chemotherapeutic agents known in the art in combination with the TP53-targeted therapy or immunotherapy and the STING agonist.Methods of treatment and uses

[0145] Also disclosed herein are methods of: restoring HLA expression in cancer cells, potentiating a TP53-targeted cancer therapy, treating or inhibiting progression of cancer or tumour growth in a subject, comprising administering to the subject a STING agonist and optionally, a TP53-targeted cancer therapy (such as a TP53-targeting vaccine or an immunotherapy that requires HLA expression).

[0146] The term “co-administering” as used herein encompasses both simultaneous and sequential administration of the TP53-targeted cancer therapy or immunotherapy and the STING agonist, and is intended to encompass any administration schedule of the two drugs that ensure either both drugs are therapeutically active in the subject at a1006167084given point in time and / or during a given treatment window. In other words, and to be clear, co-administration refers to that both therapies must be administered to the subject as part of their cancer treatment, but is not intended to limit both therapies to being administered to the patient at the exact same time and / or in the exact same dosage form. The methods described herein treat cancer in a subject by administering to the subject a synergistic combination of a STING agonist and TP53-targeted cancer therapy or immunotherapy.

[0147] The term “treating” as used herein refers to reducing, alleviating or ameliorating one or more symptoms of a disease or condition, inhibiting a disease or condition or symptom thereof, alleviating or ameliorating a disease or condition, causing regression of a disease or condition, and preventing or inhibiting a disease from progression. In some embodiments, “treatment” includes induction therapy for newly diagnosed malignant disease, maintenance therapy to maintain regression, and / or therapy to treat refractory (non-drug responsive) or relapsed (progression after remission) malignant disease.

[0148] The term “cancer” as used herein refers to a disease characterised by neoplasm(s) or tumour(s) caused by abnormal, uncontrolled cell growth, and includes diseases involving both pre-malignant cells and malignant cells. Particularly suitable cancers for treatment with the combinations described herein are discussed further below.

[0149] The term “subject” as used herein refers to human and non-human mammals. In some embodiments, the subject is a mammal. In other embodiments, the subject is a human. In some embodiments, the subject is a non-human mammal.

[0150] In some embodiments, the methods of treating or inhibiting progression of cancer in a subject herein comprise co-administering to the subject a therapeutically effective amount of a TP53-targeting therapy or immunotherapy and a therapeutically effective amount of a STING agonist. The term “effective amount” as used herein in the context of a therapeutically effective amount refers to a dose of an active compound, such as of a TP53-targeting vaccine or STING agonist, that prevents disease progression (in some embodiments, termed “manages”), alleviates, substantially reduces, or completely reduces one or more symptoms and / or causes of the disease or condition being treated. In some embodiments, the amount of TP-53 targeting therapy1006167084and STING agonist used in the combination therapies described herein is an amount that provides a significant reduction in the clinical symptoms of the disease or condition being treated, in some embodiments without causing excessive or intolerable toxic side effects to the subject.

[0151] In one embodiment, the STING agonist is intravenously administered. In one embodiment, the method includes oral or intravenous administration of the STING agonist in combination with the TP53-targeting therapy. The administration may be simultaneous or sequential as described in the section above entitled “Combinations”.

[0152] As further described above, in one embodiment, the STING agonist is administered in an amount of from about 50 pg / week to about 6,400 pg / week.

[0153] Also described herein is a method of treating or inhibiting progression of cancer or tumour growth in a subject with a cancer, comprising: identifying the subject as a candidate for TP53-targeting therapy; identifying the cancer as comprising cells expressing STING protein; and administering to the subject both a TP53-targeting therapy and a STING agonist, wherein the STING agonist is administered sequentially or simultaneously with the TP53-targeting therapy.

[0154] In the methods described herein, the cancer may be a blood cancer, or it may be a solid cancer. In some embodiments, the cancer is a TP53 wild type cancer, is a TP53-mutant cancer, or is a cancer comprising both TP53 wild type and TP53-mutant cell subpopulations. In one embodiment, the cancer is one that expresses STING protein.

[0155] When the cancer is a blood cancer, the blood cancer may be selected from leukaemia, malignant lymphoma (ML), multiple myeloma (MM), and myelodysplastic syndrome (MDS), or a relapsed / refractory form of any one of these. The cancer may be a leukaemia subtype selected from acute myeloid leukaemia (AML), including promyelocytic leukaemia, chronic myeloid leukaemia (CML), and acute lymphoblastic leukaemia (ALL), or a relapsed / refractory form of any one of these. In some embodiments, the cancer being treated by the methods herein is a lymphoma. The lymphoma may be a non-Hodgkin's lymphoma (NHL). In such embodiments, the nonHodgkin's lymphoma may be selected from adult T cell lymphoma, lymphoblastic lymphoma, diffuse large B-cell lymphoma, Burkitt's lymphoma, peripheral T cell1006167084lymphoma, follicular lymphoma, B-cell acute lymphocytic leukaemia, chronic lymphocytic leukaemia / small lymphocytic lymphoma, marginal zone lymphoma, Waldenstrom's macroglobulinaemia, and mantle cell lymphoma, or a relapsed / refractory form of any one of these. In some embodiments, the non-Hodgkin's lymphoma may be selected from adult T cell lymphoma, lymphoblastic lymphoma, peripheral T cell lymphoma, follicular lymphoma, B-cell acute lymphocytic leukaemia, chronic lymphocytic leukaemia / small lymphocytic lymphoma, marginal zone lymphoma, Waldenstrom's macroglobulinaemia, and mantle cell lymphoma, or a relapsed / refractory form of any one of these. In some embodiments, the non-Hodgkin's lymphoma excludes B-cell lymphoma and Burkitt’s lymphoma. In some embodiments, the cancer is a blood cancer selected from acute myeloid leukaemia (AML), including TP53 mutant AML, Natural Killer / T cell lymphoma (NKTL), extra nodal NK / T cell lymphoma (ENKTL), TP53 mutant NKTL, chronic lymphocytic leukaemia (CLL) and multiple myeloma. In some embodiments, the cancer is a blood cancer selected from acute myeloid leukaemia (AML), including TP53 mutant AML, and extra-nodal Natural Killer / T cell lymphoma (ENKTL), and TP53 mutant NKTL.

[0156] In some embodiments, the cancer is a AML. The AML may comprise cancer cells expressing TP53 wild type protein, a TP53-mutant protein, or both TP53 wild type and a TP53-mutant cell subpopulations.

[0157] In embodiments, the methods described herein involving treatment with STING agonist may treat (or prevent progression of) cancer cells expressing a TP53-mutant protein. This may be advantageous in the treatment of cancers comprising expression of TP53 wild type protein, a TP53-mutant protein, or both TP53 wild type and a TP53- mutant cell subpopulations. For example, in some embodiments, the methods comprise directly targeting TP53 mutant cell populations, and / or preventing or inhibiting the proliferation of TP53 mutant cell populations.

[0158] In some embodiments, the cancer is a solid cancer. In some embodiments, the solid cancer is selected from small cell lung cancer, non-small cell lung cancer, squamous cell carcinoma, melanoma, breast cancer, ovarian cancer, neuroblastoma, prostate cancer, and colorectal cancer.

[0159] In some embodiments, the cancer is not breast cancer.1006167084

[0160] The term “dose” as used herein, unless the context indicates otherwise, refers to a mass, conventionally in milligrams (mg) or micrograms (pg), of an active substance administered to a subject per kilogram (kg) of a subject's body weight.

[0161] The term “about” as used herein refers in some embodiments to an amount within ± 10%, or ± 5%, or ±2 % of the value modified by the term.

[0162] It should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “from x to y” or “between x and y” is intended to include all sub-ranges between x and y and also range end points x and y.

[0163] As used herein, the singular forms “a,” “an,” and “the” may refer to plural articles unless specifically stated otherwise.

[0164] The salts of the compounds described herein are preferably pharmaceutically acceptable, but it will be appreciated that non-pharmaceutically acceptable salts also fall within the scope of the present disclosure, for example, as these may be useful as intermediates in the preparation of pharmaceutically acceptable salts or in methods not requiring administration to a subject.

[0165] The term “pharmaceutically acceptable” may be used to describe any salt, solvate, tautomer, N-oxide, stereoisomer and / or prodrug thereof, or any other compound which upon administration to a subject, is capable of providing (directly or indirectly) a compound or an active metabolite or residue thereof and typically that is not deleterious to the subject.

[0166] Suitable pharmaceutically acceptable salts include, but are not limited to, salts of pharmaceutically acceptable inorganic acids such as hydrochloric, sulphuric, phosphoric, nitric, carbonic, boric, sulfamic, and hydrobromic acids, or salts of pharmaceutically acceptable organic acids such as acetic, propionic, butyric, tartaric, maleic, hydroxymaleic, fumaric, malic, citric, lactic, mucic, gluconic, benzoic, succinic, oxalic, phenylacetic, methanesulphonic, toluenesulphonic, benzenesulphonic, salicylic, sulphanilic, aspartic, glutamic, edetic, stearic, palmitic, oleic, lauric, pantothenic, tannic, ascorbic and valeric acids.1006167084

[0167] Base salts include, but are not limited to, those formed with pharmaceutically acceptable cations, such as sodium, potassium, lithium, calcium, magnesium, zinc, ammonium, alkylammonium such as salts formed from triethylamine, alkoxyammonium such as those formed with ethanolamine and salts formed from ethylenediamine, choline or amino acids such as arginine, lysine or histidine. General information on types of pharmaceutically acceptable salts and their formation is known to those skilled in the art and is as described in general texts such as “Handbook of Pharmaceutical salts” P.H. Stahl, C.G. Wermuth, 1st edition, 2002, Wiley-VCH.

[0168] In the case of compounds that are solids, it will be understood by those skilled in the art that the inventive compounds, agents and salts may exist in different crystalline or polymorphic forms, all of which are intended to be within the scope of the present invention and specified formulae.

[0169] The invention includes all crystalline forms of compounds described herein including anhydrous crystalline forms, hydrates, solvates and mixed solvates. If any of these crystalline forms demonstrates polymorphism, all polymorphs are within the scope of this invention.

[0170] The compounds described herein are intended to cover, where applicable, solvated as well as unsolvated forms of the compounds. Thus, the compounds described herein include compounds having the indicated structures, including the hydrated or solvated forms, as well as the non-hydrated and non-solvated forms.

[0171] The compounds described herein or salts, tautomers, N-oxides, polymorphs or prodrugs thereof may be provided in the form of solvates. Solvates contain either stoichiometric or non-stoichiometric amounts of a solvent, and may be formed during the process of crystallization with pharmaceutically acceptable solvents such as water, alcohols such as methanol, ethanol or isopropyl alcohol, DMSO, acetonitrile, dimethyl formamide (DMF), acetic acid, and the like with the solvate forming part of the crystal lattice by either non-covalent binding or by occupying a hole in the crystal lattice. Hydrates are formed when the solvent is water, alcoholates are formed when the solvent is alcohol. Solvates of the compounds described herein can be conveniently prepared or formed during the processes described herein. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of the invention.1006167084

[0172] Basic nitrogen-containing groups may be quarternised with such agents as C1 - 6alkyl halide, such as methyl, ethyl, propyl, and butyl chlorides, bromides and iodides; dialkyl sulfates like dimethyl and diethyl sulfate; and others.

[0173] Nitrogen containing groups may also be oxidised to form an N-oxide.

[0174] The compounds described herein or salts, tautomers, N-oxides, solvates and / or prodrugs thereof that form crystalline solids may demonstrate polymorphism. All polymorphic forms of the compounds, salts, tautomers, N-oxides, solvates and / or prodrugs are within the scope of the invention.

[0175] The compounds described herein may demonstrate tautomerism. Tautomers are two interchangeable forms of a molecule that typically exist within an equilibrium. Any tautomers of the compounds described herein are to be understood as being within the scope of the invention.

[0176] The compounds described herein may contain one or more stereocentres. All stereoisomers of the compounds of formula (I) are within the scope of the invention. Stereoisomers include enantiomers, diastereomers, geometric isomers (E and Z olephinic forms and cis and trans substitution patterns) and atropisomers. In some embodiments, the compound is a stereoisomerically enriched form of the compound of formula (I) at any stereocentre. The compound may be enriched in one stereoisomer over another by at least about 60, 70, 80, 90, 95, 98 or 99%.

[0177] The compounds described herein or salts, tautomers, solvates, N-oxides, and / or stereoisomers thereof, may be isotopically enriched with one or more of the isotopes of the atoms present in the compound. For example, the compound may be enriched with one or more of the following minor isotopes: 2H, 3H, 13C, 14C, 15N and / or 170, preferably 2H. An isotope may be considered enriched when its abundance is greater than its natural abundance.

[0178] A "prodrug" is a compound that may not fully satisfy the structural requirements of the compounds provided herein, but is modified in vivo, following administration to a subject or patient, to produce a compound of formula (I) provided herein. For example, a prodrug may be an acylated derivative of a compound as provided herein. Prodrugs include compounds wherein hydroxy, carboxy, amine or sulfhydryl groups are bonded to any group that, when administered to a mammalian subject, cleaves to form a free1006167084hydroxy, carboxy, amino, or sulfhydryl group, respectively. Examples of prodrugs include, but are not limited to, acetate, formate, phosphate and benzoate derivatives of alcohol and amine functional groups within the compounds provided herein. Prodrugs of the compounds provided herein may be prepared by modifying functional groups present in the compounds in such a way that the modifications are cleaved in vivo to generate the parent compounds.

[0179] Prodrugs include compounds wherein an amino acid residue, or a polypeptide chain of two or more (eg, two, three or four) amino acid residues which are covalently joined to free amino, and amido groups of compounds of Formula (I). The amino acid residues include the 20 naturally occurring amino acids commonly designated by three letter symbols and also include, 4-hydroxyproline, hydroxylysine, demosine, isodemosine, 3-methylhistidine, norvlin, beta-alanine, gamma-aminobutyric acid, citrulline, homocysteine, homoserine, ornithine and methionine sulfone. Prodrugs also include compounds wherein carbonates, carbamates, amides and alkyl esters which are covalently bonded to the above substituents of compounds described herein through the carbonyl carbon prodrug sidechain.

[0180] Non-limiting examples will now be described, to further illustrate exemplary embodiments of the invention.Examples

[0181] Example 1 : Materials and methods

[0182] CRISPR Knock out of TP53: For AML cell lines MOLM13 and MV411 , six sgRNAs targeting human TP53 were synthesized (Integrated DNA Technology) and cloned into pKLV-U6gRNA(Bbsl)PGKpuro2ABFP. Virus was made in HEK cells, and AML cell lines were transfected by a spinfection protocol prior to being selected by sorting on BFP positive cells.

[0183] Generation of TP53 mutant cell lines: Vectors containing TP53 mutant sequences were cloned into a pLV[Exp]-Puro-EF1 A vector and virus was generated in HEK cells, and AML cell lines were transfected by a spinfection protocol. Cells were sorted on fluorescent markers specific to each TP53 mutant. Mutation presence was confirmed by sanger sequencing.1006167084

[0184] Surface proteomics: Cells were cultured for 48 hours in RPMI + 10% FCS before being processed for mass-spectrometry analysis. Processing involved counting cells to ensure all replicates have even cell numbers before washing cells twice in ice cold PBS pH 7.4. Surface proteins were labelled by biotinylation using 200 uM amino- oxy-biotin, 1 mM sodium meta-periodate and 10 mM aniline in PBS pH 6.7. of proteins on the cell surface. Samples were then placed in a cold room rotating end-over-end for 1 hour. Following labelling, glycerol was added to mixture to quench reaction and cells were pelleted by spinning at 500G for 5 minutes. Cells were then washed in ice cold PBS pH 7.4 twice before being lysed using 1 % Triton X-100, 150mM NaCI, 1 X protease inhibitor (complete, without EDTA, Roche), 5mM iodoacetamide and 10mM Tris-HCI pH 7.6. Samples were then placed in a cold room rotating end-over-end for 30 minutes. Cells were pelleted by spinning at 500G for 5 minutes and supernatant was taken for further processing. Biotinylated proteins were enriched from lysate using streptavidin-sepharose beads which were then transferred to FASP spin-columns. Spin columns were then washed with Urea / 100 mM Tris pH 7.6 and spun at 14,000G for 15 minutes. Samples were then denatured and cleaved. Peptides were then collected and analysed on a timsTOF Pro mass spectrometer using dia-PASEF, and data searched using DIA-NN. For each sample, at least three technical replicates will be processed with 2 million cells per replicate.

[0185] STING agonist titrations: Cells were plated into 96-well flat-bottom plates in duplicate and drugs added at indicated concentrations. After 24 hours cells were transferred into a round-bottom 96-well plate, spun down at 1500 rpm for 5 min, and processed for flow cytometry.

[0186] STING agonist 30-minute exposure: Cells were plated into 96-well roundbottom plates in duplicate and drugs added at indicated concentrations. After 30 minutes cells spun down at 1500 rpm for 5 min, then washed once with PBS before replating in RPMI + 10% FCS. Samples were taken at specified time points and processed for flow cytometry.

[0187] Patient samples: Bone marrow and peripheral blood samples were collected from patients treated at The Peter MacCallum Cancer Center and The Alfred Hospital (Melbourne, Australia) who had newly diagnosed or morphologically relapsed AML. Peripheral blood samples from healthy donors (equal numbers male and female) were collected at the Walter and Eliza Hall Institute of Medical Research (Melbourne,1006167084Australia). Samples were collected after informed consent and studies were conducted in accordance with the approved protocols through the Human Research Ethics Committee of the respective institutions and the Declaration of Helsinki. Mononuclear cells were isolated using Ficoll density gradient. Freshly processed or thawed cryopreserved cells were used for assays.

[0188] Flow cytometry: Cells were transferred into a 96 well plate and pelleted by centrifugation at 500G for 5 minutes. Cells were then washed in PBS and pelleted again by centrifugation before proceeding with staining. Live-dead yellow was added to cells at 1 :1000 in PBS to stain for cell viability and incubated for 30 minutes on ice. Cells were then pelleted at 500G for 5 minutes before being resuspended in antibodies diluted in PBS + 2% FCS as required and incubated on ice for 1 hour. Cells were then pelleted by centrifugation at 500G for 5 minutes and resuspended in PBS + 2% FCS and data was collected on a Cytek Aurora and analysed using FlowJo.

[0189] RNA sequencing: For comparisons between WT and TP53 KO cells, cells were routinely cultured in RPMI + 10% FCS in a 10% CO2 incubator and cell pellets were frozen as required. For cells treated with STING agonist, 10 nM STING agonist or DMSO control was added, and cells were grown for a further 24 hours. Cell pellets were collected after 24 h and snap frozen. RNA was extracted using a Qiaen RNeasy kit according to the manufacturer’s instructions and 200 ng used per sample far sequencing. Paired-end sequencing was performed by the Australian Genome Research facility (AGRF).

[0190] In vivo experiments: All experiments with animals followed the guidelines of the Melbourne Directorate Animal Ethics Committee and were approved by The Walter and Eliza Hall Institute of Medical Research Ethics Committee. Mice were group-housed (up to 6 per cage) and maintained on Barastoc rodent diet. For experiments, littermates were randomly assigned to treatment arms. For AML patient derived xenograft (PDX) experiments, healthy / VSG-SG3 (female, 8 weeks old) mice were intravenously injected with 5 x 105cryopreserved patient AML samples. Human leukemia engraftment was confirmed using flow cytometric analysis of submandibular peripheral blood for the presence of hCD45+ cells. Upon confirmation of engraftment, mice received a single dose of 1 .5 mg / kg STING agonist or control. At 24 and 48 hours, mice were anesthetized with isofluorane and administered with analgesics 0.1 mg / kg buprenorphine and 5 mg / kg carprofen. Femoral bone marrow was aspirated using a 27-1006167084gauge syringe and needle. At 72 and 96 hours, mice were euthanised using CO2 and bone marrow was harvested. Cells were then stained for flow cytometry using an Aurora flow cytometer (Cytek).

[0191] Global proteomics: Cells were cultured for 24 hours in RPMI + 10% FCS with or without addition of drug (STING agonist or HDM201 ) before being processed for mass-spectrometry analysis. Processing involved counting cells to ensure all replicates have even cell numbers before washing cells twice in ice cold PBS and pelleting cells. Samples were then denatured and cleaved. Peptides were then collected and analysed on a timsTOF Pro mass spectrometer using dia-PASEF, and data searched using DIA- NN.

[0192] Determination of STING expression: Bone marrow (BM) or peripheral blood (PB) from 26 patients with AML or MDS-EB (myelodysplastic syndrome with excess blasts), and PB from 9 different healthy donors, were processed as follows. Up to 1 million cells were stained per sample, MOLM-13 wild type and STING KO cells run as controls. Samples were stained with LIVE / DEAD yellow (Fixable Yellow Dead Cell Stain Kit, Invitrogen, catalogue no L34959) for viability, then stained for surface markers (indicated below), fixed / permeabilised, and then stained for STING expression (BD Pharminogen Alexa Fluor 647 Mouse Anti-Human STING, BD, Catalogue no 564836). Flow cytometry was performed using Cytek Aurora.

[0193] Table 2: Antibodies used for flow cytometry to characterise AML patient samples and / or normal donor samples1006167084

[0194] Surface Plasmon Resonance (SPR)

[0195] Binding interactions of ligands with STING proteins were quantified using Surface Plasmon Resonance (SPR) with a minimally biotinylated STING protein immobilized on a streptavidin chip surface. In this manner highly active STING protein surfaces were obtained that were not compromised by a low pH required for an amine coupling method. Minimal biotinylation of purified huSTING proteins was performed using a previously described methodology (Chhabra 2012).

[0196] SPR was determined by methods similar to those described in WO 2021 / 119753 A1 (US12415785). Briefly, approximately 20 nmol of recombinant STING protein in 1 x TBS buffer (25 mM Tris-HCI, pH 7.5, 150 mM NaCI, 5 mM DTT) was mixed with of EZ-Link™ Sulfo-NHS-LC-LC-Biotin (Thermofisher Scientific, cat# 21338) at a molar ratio of 1 to 0.6 and incubated on ice for 2 hours. To remove any unreacted biotin reagent, protein / biotin mixture was passed through a Superdex 75 (10 / 300 GL) column equilibrated with 10 mM HEPES, pH7.4, 150 mM NaCI, 5 mM DTT, 5 %[v / v] glycerol. A protein peak containing biotinylated huSTING protein was collected and stored in aliquots at -80 °C.

[0197] Streptavidin was simultaneously immobilized in all four channels of a CM5 sensor chip docked in a Biacore instrument (either Biacore S200 or Biacore T200, GE Healthcare) as described previously (Zender 2013). Minimally biotinylated STING protein was captured onto a streptavidin coated chip surface at 8 °C in SPR binding buffer (50 mM HEPES, pH 7.4, 150 mM NaCI, 2 %[v / v] DMSO) by gradually injecting in a single channel at a constant flow-rate of 2 pL / min until desired capture level was achieved, typically 3000 to 7000 Rll (1 Rll = 1 pg / mm2).

[0198] All binding experiments were performed at 8 °C in SPR binding buffer. To determine binding affinity, compound interaction with immobilized STING protein was analysed using dose-response experiments. Fresh 10 mM DMSO solutions of compound were diluted directly into SPR binding buffer typically to a concentration of 50 pM and then further diluted 2-fold or 3-fold aiming for either a 5- or 7-point concentration series range. Each ligand concentration series was injected at a constant flow rate of 60 pL / min with a 90 second association and a 180 second dissociation time. These were modified for compounds with longer residence times, so that curves could reach steadystate, or so that compound would be fully dissociated before the subsequent injection.1006167084Where appropriate, tighter-binding compounds (roughly Ko < 1 uM) were tested using a single-cycle kinetics format (Karlsson 2006), with long association and dissociation times (typically 450 s and 1800 s, respectively).

[0199] Scrubber 2 (www.biologic.com.au) was utilized for data processing, where signals were referenced against the blank surface (streptavidin + D-biotin) and further corrected for DMSO refractive index change and then “double-referenced” using a buffer-blank injection (Papalia 2006). Responses were fitted to either a 1 :1 steady-state affinity model or a 1 :1 kinetic model (that included a mass-transport component), available within Scrubber.Table 3: SPR results for STING agonists ACU-0943, ACU-2086 and ACU-0514 / DiABZI*Note: * ACU-0514 and DiABZI refer to the same compound, and accordingly are used interchangeably in this specification.

[0200] Example 2: Proteomic analysis and RNA analysis of TP53 knock out (KO) cells relative to wild type (WT) cell lines (MV411 and MOLM13).

[0201] A mass-spectrometry based surfaceome screen identified reduced MHC / HLA (Class I (ABC) and Class II (DR DP DQ)) expression in TP53 knock out (KO) cells relative to wild type (WT) cell lines (MV411 and MOLM13). Figure 1A shows volcano plots of MV411 and MOLM13 cell lines highlighting differential expression of MHC molecules comparing WT to TP53 KO cells as determined by surface proteomics.

[0202] In both MV411 and MOLM13 AML cell lines, when the TP53 gene is knocked out, there is a significant reduction in (Major Histocompatibilty Complex) MHC molecule expression on the cell surface (also known as Human Leukocyte Antigens (HLAs)).1006167084These MHC molecules are essential for presenting antigens to the immune system (particularly to T cells) and as such the inventors hypothesise that decreased expression would both decrease ability of the immune system to recognise and kill cancer cells, and would also hinder the efficacy of immune based therapies that rely on MHC expression and presentation of antigens to T cells.

[0203] Figure 1 B shows volcano plots of comparative RNA analysis of TP53 WT and KO MOLM13 and MV411 cells revealed minimal differential regulation of genes associated with MHC peptide processing and presentation. RNA expression was determined according to the RNA sequencing protocols outlined above.

[0204] These results shown in Figure 1 B indicate that alterations in MHC surface expression are likely driven at the protein or post-translational level rather than transcriptom ic level as the majority of genes are not significantly different between WT and TP53 KO cells.

[0205] Example 3: Point mutations in TP53 in AML

[0206] The 4 most common TP53 point mutations in AML are R175H, Y220C, R248W and R273H. The inventors generated cell lines expressing these 4 mutants to investigate their link to HLA expression further in both MOLM13 and MV411 cell lines.

[0207] Figure 2 (left) shows lollipop plots generated from AML patients with TP53 mutations highlighting the four most common mutations at residues R175, Y220, R248 and R273. Figure 2 (right) shows a schematic diagram depicting the process of generating cell lines expressing these 4 mutants; TP53 KO cell lines of MV411 and MOLM1 3 AML lines (WT for TP53) were generated by CRISPR and the 4 mutant TP53 variants were overexpressed in these cells using lentivirus, generating stably expressing TP53 mutants with fluorescent proteins labelled for cell tracking.

[0208] Point mutations in the DNA binding domain of TP53 are the most common mutations of the TP53 gene in patients, and as such the inventors chose to generate cell lines representing the four most common mutations in AML to study. These cell lines are being used to recapitulate what may be seen in AML patient samples with TP53 aberrations. The subsequent data is from the MOLM13 cell line unless specified, however duplicate experiments have also been performed with the MV411 cell line with similar results.1006167084

[0209] Example 4: Expression of mutated TP53 leads to reduced HLA expression in AML cell lines at baseline.

[0210] Figures 3A and 3B show the decreased expression of MHC expression in TP53 mutant cell lines relative to WT. Figure 3A shows representative FACS plots showing decreased expression of HLA-ABC and HLA_DR / DP / DQ on TP53 mutant cell lines relative to the empty vector control with WT TP53. Figure 3B shows volcano plots of decreased HLA ABC expression in TP53 mutant cell lines (R175H, Y220C, R248W and R273H) when compared to WT as determined by surface proteomics.

[0211] These are the four most common TP53 point mutations in AML patients, and as was seen with the TP53 KO cell lines, there is decreased expression of MHC / HLA molecules on the surface of these cells, relative to their WT counterparts. Point mutations are more common than complete loss of TP53 in patients (although this does occur in some cases), and so these results highlight that any TP53 aberration appears to lead to a decrease in expression of HLAs, particularly class I (ABC).

[0212] Figure 3C shows expression of MHC class I globally in cells. Figure 3C shows plots of Log2 expression of HLA-A, B and C across MOLM13 and MV411 WT, TP53 KO and mutant cell lines as measured by global proteomics shows non-significant differences. These results suggest that changes in MHC levels at the cell surface are not due to overall lower MHC levels being produced within the cell but instead protein being presented at the cell surface. This may be due to peptide processing, loading or other mechanisms.

[0213] Example 5: In TP53 mutant cells, defective HLA-ABC expression is restored by exposure to STING agonists ACU-2086 and ACU-0514.

[0214] Figure 4 shows that STING agonists can increase HLA expression in cell lines irrespective of TP53 status. ACU-2086 (Figure 4A) and ACU-0514 (Figure 4B) were able to increase expression of HLA Class I (ABC) molecules on cell surface in a dosedependent manner following 24 hours of continuous exposure.

[0215] These results show that treatment with STING agonists (ACU-0514 or ACU- 2086) induces a robust increase in HLA expression after 24 hours of continuous exposure. This increase occurs in a STING-dependent manner as highlighted by the lack of response in the STING KO model. The empty vector control model is WT for1006167084TP53 and there was a slight increase in HLA expression from baseline (0 nM dose), however in the TP53 mutant cell lines there is a dramatic increase in HLA expression from baseline, even when compared to the TP53 KO.

[0216] Figure 5 shows that STING agonist ACU-0943 can increase HLA expression in AML cell lines following 30-minute drug exposure. Increased HLA Class I (ABC) expression can be seen from as little as 4 hours and up to 48 hours following a 30- minute exposure to ACU-0943 in the TP53 mutant cells (R175H, Y220C, R248W and R273H).

[0217] Following exposure to ACU-0943 for 30 minutes at 10 nM, 100 nM and 500 nM, there is an increase in HLA expression in all cell lines over 100 nM by 24 hours and by 48 hours for all cell lines at the lowest dose of 10 nM. This is important for understanding how to combine STING agonists with immune-based therapies to get maximum response. Based on these results, after a single dose of ACU-0943, 24 hours later it is envisaged that it will be possible to give an immune-based therapy and see the maximum therapeutic response as there is upregulation of HLAs at this time point across most concentrations.

[0218] Figure 4C shows that MHC class I gene expression increases with STING agonist treatment. MOLM13 cell lines (WT, STING KO, TP53 KO, and R175H, Y220C, R248W, and R273H mutants) were treated with 10 nM DiABZI STING agonist or DMSO control for 24 hours. These data suggest that addition of DiABZI STING agonist led to an upregulation of all 3 HLA genes (HLA-A, B and C) as well as B2M, which forms part of the MHC complex. Deletion of STING (STING KO) abrogated response as expected and no increase in gene expression was seen in these cells.

[0219] Figure 4D shows that global protein expression of HLAs and B2M increase with STING agonist treatment. MOLM13 cell lines either WT or STING KO were treated with DiABZI STING agonist for 24 hours. Global proteomics revealed an increase in HLA and B2M. Addition of DiABZI STING agonist led to an upregulation of all 3 HLA molecules (HLA-A, B and C) as well as B2M globally within cells. Deletion of STING (STING KO) abrogated response. Figure 4D shows global protein expression, not surface expression.1006167084

[0220] Example 6: HLA-ABC expression is not enhanced in TP53 mutant cells by exposure to cytotoxic drugs, whereas interferons alpha and gamma along with STING agonists (ACU-0514) enhance expression of HLA-ABC.

[0221] Figure 6 shows interferons alpha, gamma and STING agonists increase HLA expression in AML cell lines. Representative FACS plots from MOLM13 R175H show that cytotoxic drugs such as daunorubicin, Venetoclax and a DNMTI i do not increase HLA expression in the same manner as interferons alpha, gamma and STING agonist ACU-0514.

[0222] Following a continuous 24-hour exposure to increasing concentrations of compounds listed the inventors measured HLA Class I (ABC) and II (DR DP DQ) by flow cytometry and saw a robust increase in expression by interferons gamma, alpha and STING agonist ACU0514 which all converge upon similar pathways. This was also demonstrated for the other 3 mutant cell lines Y220C, R238W and R273H with the same pattern.

[0223] Example 7: Effect of STING agonists on cell viability

[0224] Figure 7 shows that high doses of STING agonists are able to kill TP53 mutant AML cells via apoptosis. Dose-titrations of ACU-0514 and ACU-2086 highlight that high concentrations of both compounds can trigger cell death in a robust manner.

[0225] Example 8: An increase in HLA expression can be seen in cells not undergoing apoptosis.

[0226] Figure 8 shows that HLA increase is not dependent on cell death. Using cells unable to undergo cell death, there is a robust increase in HLA class I (ABC) expression following 24-hour exposure to ACU-0943 at even low doses.

[0227] BAK / BAX double knock out (BB DKO) cell lines are unable to undergo apoptosis despite having WT TP53 as BAK and BAX are the terminal effectors of apoptosis. Here the inventors show that an increase in HLA expression happens in a cell-death independent manner.

[0228] Example 9: HLA-ABC (Class I) expression is reduced in blasts from patients with TP53 mutations, whereas HLA DR / DP / DQ (Class II) does not appear to be correlated with P53 status.1006167084

[0229] Figure 9 shows that HLA Class I (ABC) expression is reduced in blasts from patients with TP53 mutations relative to those with WT TP53. Figure 9A shows FACS plots of HLA class I (ABC) and II (DR DP DQ) expression on patient blasts show reduced expression of class I in those with TP53 mutations. The table below shows patient mutations and blast percentage for each sample. Figure 9B shows FACS plots of HLA class I (ABC) and II (DR DP DQ) expression in blasts, monocytes and lymphocytes in all patient samples showing no correlation between TP53 status and HLA expression on lymphocytes and monocytes.Table 4: Sample, Mutations and Blast% for Example 9Sample M iatio Blast %

[0230] Using a small population of samples, a decrease in HLA class I expression in TP53 mutated AML blasts was shown, but no correlation in other cellular compartments or correlation between TP53 status and HLA class II expression. This highlights that there is an intrinsic link between HLA class I expression and TP53 status.

[0231] Figure 9C shows that HLA Class I and II mean fluorescence is lower in blasts from patients with TP53 mutations relative to those with WT TP53. Class I (HLA-ABC) and class II (HLA-DR DP DQ) mean fluorescence intensity as measured by FACS. Data presented in Figure 9C are from 14 patients with AML WT for TP53 and 18 patients with TP53 mutated AML. Both MHC class I and class II had significantly lower MFI on patient samples with TP53 mutations.1006167084

[0232] Example 10: STING agonists (ACU-0943) increases HLA expression in AML blasts from patients with TP53 mutated AML.

[0233] Figure 10 shows that STING agonist ACU-0943 increases HLA class I expression on TP53 mutated AML blasts. Figure 10A shows FACS plots of HLA class I (ABC) expression on patient blasts with WT TP53 and one normal peripheral blood sample highlighting little to no change in HLA expression with exposure to ACU-0943. Figure 10B shows FACS plots of HLA class I (ABC) expression on patient blasts with mutant TP53 highlighting ability to increase HLA expression with exposure to ACU- 0943.

[0234] Here the inventors show that ACU-0943 is capable of increasing expression of HLA class I (ABC) molecules on the surface of AML blasts with TP53 mutations, however this is less pronounced in patients with WT TP53 status or in a healthy donor. These results highlight that this STING agonist driven response can be observed not only in cell lines but in AML patient samples, and specifically that this can be seen on the patient blasts (AML).

[0235] Summary

[0236] The inventors have shown that there is a link between TP53 status and HLA class I (ABC) expression on the surface of cells. HLA class I molecules present antigens to the immune system, allowing them to be recognised as defective, targeting these cells for destruction. Downregulation of HLAs is a mechanism by which cancer cells can evade the immune system which is a hallmark of cancer. Unfortunately, immune based therapies have traditionally had poor efficacy in AML, however the inventors believe the combination of STING agonists with these immune based therapies may increase therapeutic potential in AML.

[0237] Here the inventors have shown that STING agonists can increase the expression of HLA class I molecules on the surface of AML cells, and particularly in TP53 mutated AML, there is a robust restoration of HLA expression upon exposure to STING agonists.1006167084

[0238] Example 11: combination treatment

[0239] A series of experiments is conducted in which the combination of a STING agonist and a TP53-targeting agent is tested.

[0240] The different TP53-targeting agents that are assessed include: a TP53 peptide vaccine, a viral-based vaccine (such as a modified vaccine virus Ankara vaccine encoding wild-type TP53), a mutp53-derived neoantigen peptide vaccine and a TP53- targeting antibody. Examples of these are disclosed in Hassin et al,, (2023) Nature Reviews Drug Discovery, 22: 127-144, incorporated herein by reference.

[0241] T-cell activation is determined in vitro using Incucyte ® ZOOM live-cell analysis, flow cytometry and cytokine assays.

[0242] Killing of AML cell lines and patient AML samples, in vitro, is assessed by flow cytometry and CellTiter-Glo assays.

[0243] Killing of AML cell lines and patient-derived xenografts, in vivo, is assessed by flow cytometry, and histology.

[0244] The combination of STING agonist and TP53-targeting agent results in an additive or synergistic effect such that the AML cancer cell-killing capacity of the combination is greater than the cancer cell-killing effect of either the STING agonist or TP53-targeting agent alone.

[0245] Example 12: STING expression in primary human myeloid cells

[0246] Expression of STING was assessed in primary human samples, using intracellular flow cytometry. Figure 11 shows STING expression, normalized to cell line positive control, in different normal and malignant primary haematopoietic cells. Data shown include 63 independent primary PB or BM samples (41 AML / MDS-IB and 22 normal). Comparison between groups was made using one-way ANOVA with Tukey’s multiple comparison test; **=p<0.01 , ***=p<0.001 , ****=p<0.0001 .

[0247] Figure 11 shows that primary human myeloid cells demonstrate significantly higher intracellular STING expression than other haematological cell types, including B, T and NK cells. This observation highlights the potential for STING agonists to have a wider therapeutic window in AML, compared with other tumour types, as the dose1006167084threshold for triggering cytokine release syndrome (CRS) via T cell activation is likely to be higher than the dose needed for an anti-AML effect in humans.

[0248] Example 12: Single dose treatment with STING agonist

[0249] A single dose of STING agonist ACU-0943 can increases HLA expression.Figure 12A shows a schematic diagram of the experimental set up. Figure 12B shows a representative HLA-ABC fluorescence intensity by histogram of 2 mice at each time point. Figure 12C shows the fold change of HLA-ABC median fluorescence intensity from first measurement at 24 hours to second measurement at 48 hours.

[0250] Using a patient derived xenograft (PDX) model of TP53 mutated AML, mice received a single dose of DMSO control or STING agonist ACU-0943. Samples were then taken every 24 hours for 4 days. After 48 hours we saw an increase in HLA-ABC surface levels. Increased HLA-ABC surface levels remained sustained for up to 96 hours, slowly decreasing towards baseline.

[0251] It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.1006167084

Claims

1. CLAIMS1. A method of restoring or increasing HLA expression on cancer cells, the method comprising administering to a subject in need thereof, a STING agonist, thereby restoring or increasing HLA expression on cancer cells of the subject.

2. A method of potentiating an anti-cancer immunotherapy, the method comprising administering to a STING agonist to a subject who has received, is receiving or is to receive an anti-cancer immunotherapy, thereby potentiating the anti-cancer immunotherapy.

3. A method of potentiating a TP53-targeted cancer therapy, the method comprising administering to a STING agonist to a subject who has received, is receiving or is to receive TP53-targeted cancer therapy, thereby potentiating the TP53-targeted cancer therapy.

4. A method of treating or inhibiting progression of cancer in a subject, comprising co-administering to a subject in need thereof:- an anti-cancer immunotherapy; and- a STING agonist, thereby treating or inhibiting progression of cancer in the subject.

5. A method of treating or inhibiting progression of cancer in a subject, comprising co-administering to a subject in need thereof:- a TP53-targeting therapy; and- a STING agonist, thereby treating or inhibiting progression of cancer in the subject.

6. The method of claim 5, further comprising:- identifying the subject as a candidate for a TP53-targeting therapy; and / or- identifying the cancer as comprising cells expressing STING protein.10061670847. The method of any one of the preceding claims, wherein the cancer comprises cells expressing STING protein.

8. The method of any one of the preceding claims, wherein the cancer comprises TP53-wildtype and TP53-mutant / deficient cells.

9. The method of any one of claims 4 to 8, wherein the co-administering comprises administering the immunotherapy and the STING agonist simultaneously.

10. The method of any one of claims 4 to 8, wherein the co-administering comprises sequentially administering the immunotherapy and the STING agonist.11 . The method of any one of claims 5 to 8, wherein the co-administering comprises administering the TP53-targeting therapy and the STING agonist simultaneously.

12. The method of any claims 5 to 8, wherein the co-administering comprises sequentially administering the TP53-targeting therapy and the STING agonist.

13. The method of any one of claims 2, 4 and 7 to 12, wherein the immunotherapy is any immunotherapy requiring HLA expression on the cancer cells, wherein optionally the immunotherapy is selected from a genetically engineered T cell (such as a CAR T cell), a checkpoint inhibitor, a dendritic cell vaccine, an RNA or peptide vaccine or a TP53-targeting therapy.

14. The method of any one of claims 3, and 5 to 13, wherein the TP53-targeting therapy is a TP53 vaccine therapy or TP53-targeting antigen binding protein therapy (such as a TP53-binding antibody, bispecific antibody or CAR-T therapy).

15. The method of claim 14, wherein the TP53 vaccine is an mRNA, peptide, dendritic cell, or viral vaccine targeting TP53.

16. The method of any one of the preceding claims, wherein the STING agonist is selected from any one of compounds 1-1 to 1-172, 2-1 to 2-25, 3-1 to 3-24, 4-1 to 4-112 and 5-1 to 5-15, or a pharmaceutically acceptable salt thereof.

17. The method of any one of the preceding claims, wherein the STING agonist is administered in an amount of from about 10 pg / week to about 6,400 pg / week across from 1 dose every 3 weeks to 1 to 3 doses per week.100616708418. The method of any one of the preceding claims, wherein the cancer is a blood cancer.

19. The method of any one of the preceding claims, wherein the cancer is a blood cancer selected from leukaemia, such as acute myeloid leukaemia (AML), lymphoma such as T cell lymphoma and multiple myeloma (MM), or a relapsed / refractory form of any one of these.

20. The method of any one of the preceding claims, wherein the cancer is a blood cancer selected from acute myeloid leukaemia (AML), Natural Killer / T cell lymphoma (NKTL), extra nodal NK / T cell lymphoma (ENKTL), and multiple myeloma (MM), or a relapsed / refractory form of any one of these.

21. The method of any one of the preceding claims, wherein the cancer is acute myeloid leukaemia (AML).

22. The method of any one of claims 1 to 20, wherein the cancer is a lymphoma.

23. The method of any claim 22, wherein the lymphoma is non-Hodgkin's lymphoma (NHL).

24. The method of claim 23, wherein the non-Hodgkin's lymphoma selected from adult T cell lymphoma, lymphoblastic lymphoma, peripheral T cell lymphoma, follicular lymphoma, chronic lymphocytic leukemia / small lymphocytic lymphoma, Natural Killer / T cell lymphoma (NKTL), extra nodal NK / T cell lymphoma (ENKTL), marginal zone lymphoma, Waldenstrom's macroglobulinaemia, and mantle cell lymphoma, or a relapsed / refractory form of any one of these.

25. The method of any one of claims 1 to 17, wherein the cancer is a solid cancer.

26. Use of a STING agonist in the manufacture of a medicament for restoring or increasing HLA expression on cancer cells.

27. Use of a STING agonist in the manufacture of a medicament for potentiating an anti-cancer immunotherapy.

29. Use of a STING agonist in the manufacture of a medicament for potentiating a TP53-targeted therapy, optionally wherein the therapy is a TP53-vaccine or anti- TP53 antigen binding protein therapy.100616708430. Use of a TP53-targeting therapy and a STING agonist in the manufacture of a medicament for the treatment of cancer in a subject, wherein the TP53-targeting therapy and a STING agonist are for co-administration, optionally wherein the therapy is a TP53-vaccine or anti-TP53 antigen binding protein therapy.

31. The use of claim 30, wherein the co-administration is sequential or simultaneous administration.

32. Use of a STING agonist in the manufacture of a medicament for conjoint administration with a TP53-targeting therapy drug for the treatment of cancer in a subject.

33. Use of a TP53-targeting therapy in the manufacture of a medicament for conjoint administration with a STING agonist for the treatment of cancer in a subject.

34. The use of claim 32 or claim 33 wherein the conjoint administration is sequential or simultaneous administration.1006167084

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