ANTI-VISTA ANTIBODIES AND USES THEREOF

1 . An antibody, or an antigen-binding fragment thereof, that binds to V-domain Ig-containing Suppressor of T cell Activation (VISTA),

wherein the antibody, or antigen-binding fragment thereof, blocks binding of all five ligands to VISTA at pH 6.0 and pH 7.4, wherein the five known ligands to VISTA are VSIG-3 (V-set and immunoglobulin domain containing 3), VSIG-8 (V-set and immunoglobulin domain containing 8), PSGL-1 (P-selectin glycoprotein ligand-1), LRIG1 (leucine rich repeats and immunoglobulin like domains 1) and VISTA; and

wherein the antibody, or antigen-binding fragment thereof, comprises a heavy chain variable region (VH) and a light chain variable region (VL).

2 . (canceled)

3 . (canceled)

4 . An antibody, or antigen-binding fragment thereof, that binds to VISTA, wherein the antibody or antigen-binding fragment thereof, comprises a VH and a VL,

wherein the VH comprises:

a VH CDR1 of any one of SEQ ID NOs: 247-253 as defined by Kabat numbering system; any one of SEQ ID NOs: 284-291 as defined by IMGT numbering system; or any one of SEQ ID NOs: 318-325 as defined by Paratome numbering system,

a VH CDR2 of any one of SEQ ID NOs: 254-265 as defined by Kabat numbering system; any one of SEQ ID NOs: 292-298 as defined by IMGT numbering system; or any one of SEQ ID NOs: 326-339 as defined by Paratome numbering system,

a VH CDR3 of any one of SEQ ID NOs: 266-283 as defined by Kabat numbering system; any one of SEQ ID NOs: 299-317 as defined by IMGT numbering system; or any one of SEQ ID NOs: 340-359 as defined by Paratome numbering system, and

wherein the VL comprises:

a VL CDR1 of any one of SEQ ID NOs: 111-122 as defined by Kabat numbering system; any one of SEQ ID NOs: 152-162 as defined by IMGT numbering system; or any one of SEQ ID NOs: 188-196 or 576-578 as defined by Paratome numbering system,

a VL CDR2 of any one of SEQ ID NOs: 123-131 and 575 as defined by Kabat numbering system; any one of SEQ ID NOs: 163-167 as defined by IMGT numbering system; or any one of SEQ ID NOs: 197-206 as defined by Paratome numbering system, and

a VL CDR3 of any one of SEQ ID NOs: 132-151 as defined by Kabat numbering system; any one of SEQ ID NOs: 168-186 as defined by IMGT numbering system; or any one of SEQ ID NOs: 207-226 as defined by Paratome numbering system.

5 . The antibody, or antigen-binding fragment thereof, of claim 4 ,

wherein the VH comprises a sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of any one of SEQ ID NOs: 584-597, 227-246, and 383-386, and

wherein the VL comprises a sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of any one of SEQ ID NOs: 84-110.

6 . The antibody, or antigen-binding fragment thereof, of claim 4 , wherein

the VH CDR1 comprises SEQ ID NO: 249, the VH CDR2 comprises SEQ ID NO: 256, the VH CDR3 comprises SEQ ID NO: 268, the VL CDR1 comprises SEQ ID NO: 113, the VL CDR2 comprises SEQ ID NO: 125, and the VL CDR3 comprises SEQ ID NO: 134;

the VH CDR1 comprises SEQ ID NO: 286, the VH CDR2 comprises SEQ ID NO: 294, the VH CDR3 comprises SEQ ID NO: 301, the VL CDR1 comprises SEQ ID NO: 154, the VL CDR2 comprises SEQ ID NO: 165, and the VL CDR3 comprises SEQ ID NO: 170; or

the VH CDR1 comprises SEQ ID NO: 320, the VH CDR2 comprises SEQ ID NO: 328, the VH CDR3 comprises SEQ ID NO: 342, the VL CDR1 comprises SEQ ID NO: 190, the VL CDR2 comprises SEQ ID NO: 199, and the VL CDR3 comprises SEQ ID NO: 209.

7 . The antibody, or antigen-binding fragment thereof, of claim 4 , wherein

the VH CDR1 comprises SEQ ID NO: 249, SEQ ID NO: 286 or SEQ ID NO: 320, the VH CDR2 comprises SEQ ID NO: 256, SEQ ID NO: 294 or SEQ ID NO: 328, the VH CDR3 comprises SEQ ID NO: 268, SEQ ID NO: 301 or SEQ ID NO: 342, the VL CDR1 comprises SEQ ID NO: 113, SEQ ID NO: 154 or SEQ ID NO: 190, the VL CDR2 comprises SEQ ID NO: 125, SEQ ID NO: 165, or SEQ ID NO: 199, and the VL CDR3 comprises SEQ ID NO: 134, SEQ ID NO: 170 or SEQ ID NO: 209.

8 . The antibody, or antigen-binding fragment thereof, of claim 4 ,

(i) wherein the VH comprises a sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of SEQ ID NO: 592, and

wherein the VL comprises a sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of SEQ ID NO: 86; or

(ii) wherein the VH comprise a sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of SEQ ID NO: 586, and

wherein the VL comprises a sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of SEQ ID NO: 86.

9 . The antibody, or antigen-binding fragment thereof, of claim 4 ,

comprising a heavy chain (HC) sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of any one of SEQ ID NOs: 407-477, 572-574, and 604-609, and

comprising a light chain (LC) sequence having at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to, comprises, or consists of any one of SEQ ID NOs: 387-406, 569-571, and 598-603.

10 . (canceled)

11 . The antibody, or antigen-binding fragment thereof, of claim 4 ,

which binds to an epitope of human VISTA comprising the amino acid sequence 66 HLHHG 70 (amino acids 98-102 of SEQ ID NO: 377) or 116 VVEIRHHHSEHR 127 (amino acids 148-159 of SEQ ID NO: 377), or

which binds to an epitope of human VISTA comprising Tyrosine 37, Arginine 54, Valine 117 and Arginine 127 of SEO ID NO:377 (respectively amino acids 69, 86, 149 and 159 of SEO ID NO:377).

12 . (canceled)

13 . The antibody, or antigen-binding fragment thereof, of claim 4 , comprising an Fc region,

optionally wherein the Fc region is a human Fc region or a variant of the human Fc region that has in the range of one to seven amino acid mutations in the Fc region relative to the native human Fc region, and/or

optionally wherein the human Fc region is of a human IgG1, human IgG2, or a human IgG4, further optionally wherein the antibody comprises a constant region of a human IgG1 or a human IgG4 or a variant of the constant region that has in the range of one to seven amino acid mutations in the constant region relative to the native constant region.

14 . The antibody, or antigen-binding fragment, of claim 13 , wherein

(a) the Fc region is of a human IgG1, and wherein the mutations are selected from the group consisting of C220D, D221C, E233P, L234A, L234E, L234Y, L235A, L235E, L235F, G236A, G236W, G236R, G237A, P238S, S239D, F241A, M252Y, S254T, T256E, T256N, V264A, D265A, S267E, H268F, H268A, D270A, H268Q, E294deletion, N297A, N297G, N297E, S298A, T307P, E318A, K322A, S324T, K326A, K326M, L328R, P329A, P329G, A330L, A330S, P331A, P331S, I332E, E333A, E333S, K334A, A378V, S383N, M428L, N434S, and N434Y, wherein the residues are numbered using the EU numbering system;

(b) the Fc region is of a human IgG2, and wherein the mutations are selected from the group consisting of C220D, G237A, P238S, S239D, F241A, M252Y, S254T, T256E, T256N, V264A, D265A, S267E, H268F, H268A, D270A, H268Q, E294deletion, N297A, N297G, N297E, S298A, T307P, V309L, E318A, K322A, S324T, K326A, K326M, L328R, P329A, P329G, A330L, A330S, P331A, P331S, I332E, E333A, E333S, K334A, S383N, M428L, N434S, and N434Y, wherein the residues are numbered using the EU numbering system; or

(c) the Fc region is of a human IgG4, and wherein the mutations are selected from the group consisting of S228P, E233P, F234A, L235A, L235E, L235F, G236A, G236W, G236R, G237A, P238S, S239D, F241A, M252Y, S254T, T256E, T256N, V264A, D265A, S267E, H268F, H268A, D270A, H268Q, E294deletion, N297A, N297G, N297E, S298A, T307P, V309L, E318A, K322A, S324T, K326A, K326M, L328R, P329A, P329G, I332E, E333A, E333S, K334A, A378V, S383N, M428L, N434S, and N434Y, wherein the residues are numbered using the EU numbering system.

15 . The antibody, or antigen-binding fragment thereof, of claim 4 , which is a bispecific antibody or a multispecific antibody.

16 . The antibody, or antigen-binding fragment thereof, of claim 4 , wherein the antigen-binding fragment is an Fv fragment, a Fab fragment, a F(ab′)2 fragment, or a single-chain Fv (scFv).

17 . (canceled)

18 . An antibody-drug conjugate comprising the antibody, or antigen-binding fragment thereof, of claim 4 and a therapeutic agent.

19 . A chimeric antigen receptor (CAR) comprising the scFv of claim 16 .

20 . A polynucleotide comprising a nucleotide sequence encoding the VH, the VL, or the VH and the VL of the antibody, or antigen-binding fragment thereof, of claim 4 .

21 . A cell comprising one or more polynucleotides encoding the antibody, or antigen-binding fragment thereof, of claim 4 .

22 . A pharmaceutical composition comprising the antibody, or antigen-binding fragment thereof, of claim 4 and a pharmaceutically acceptable carrier.

23 . A method of producing an antibody, or antigen-binding fragment thereof, the method comprising culturing the cell of claim 21 under conditions such that said one or more polynucleotides are expressed by the cell to produce the antibody, or antigen-binding fragment thereof, encoded by the polynucleotides.

24 . A method of treating cancer, an autoimmune disease, and/or an infection in a subject in need thereof, comprising administering to the subject the pharmaceutical composition of claim 22 .

25 . The method of claim 24 , wherein the cancer is a non-small cell lung cancer, small cell lung cancer, a head and neck squamous cell carcinoma, an hepatocellular carcinoma, an ovarian cancer, a neuroblastoma, an oral cancer, a thyroid cancer, a breast cancer, a sarcoma, a pancreatic cancer, a colon cancer, a gastric cancer, a choriocarcinoma, a testicular cancer, a mesothelioma, a skin cancer, a renal cell carcinoma, a bladder cancer, a hematological cancer, a cervical cancer, a blood cancer, an acute myeloid leukemia, myelodysplastic syndrome, and/or a metastatic cancer.

26 . (canceled)

27 . (canceled)

28 . The method of claim 24 , wherein the method further comprises administering to the subject an additional therapy, optionally wherein the additional therapy is radiotherapy, a chemotherapeutic agent, a targeted therapy, a tyrosine kinase inhibitor, hormone therapy, and/or an immune checkpoint inhibitor.

29 . The method of claim 28 , wherein the immune checkpoint inhibitor is an inhibitor of Programmed Death-1 (PD-1), or Programmed death-ligand 1 (PDL1), or cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), or lymphocyte-activation gene 3 (LAG-3).