ACTIVATABLE BISPECIFIC ANTI-CD47 AND ANTI-PD-L1 PROTEINS AND USES THEREOF

1 . A protein comprising a heavy chain and a light chain,

wherein the heavy chain comprises, in N-terminus to C-terminus order, an anti-PD-L1 heavy chain variable (VH) domain, a CH domain, a first linker, an anti-CD47 VH domain, and an immunoglobulin heavy chain constant region;

wherein the light chain comprises, in N-terminus to C-terminus order, an anti-PD-L1 light chain variable (VL) domain, a first immunoglobulin light chain constant region, a second linker, an anti-CD47 VL domain, and a second immunoglobulin light chain constant region;

wherein the anti-PD-L1 VH domain comprises a HCDR1 comprising the amino acid sequence of SEQ ID NO: 1, a HCDR2 comprising the amino acid sequence of SEQ ID NO: 2, and a HCDR3 comprising the amino acid sequence of SEQ ID NO: 3;

wherein the anti-PD-L1 VL domain comprises a LCDR1 comprising the amino acid sequence of SEQ ID NO: 4, a LCDR2 comprising the amino acid sequence of SEQ ID NO: 5, and a LCDR3 comprising the amino acid sequence of SEQ ID NO: 6;

wherein the anti-CD47 VH domain comprises a HCDR1 comprising the amino acid sequence of SEQ ID NO: 7, a HCDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a HCDR3 comprising the amino acid sequence of SEQ ID NO: 9;

wherein the anti-CD47 VL domain comprises a LCDR1 comprising the amino acid sequence of SEQ ID NO: 10, a LCDR2 comprising the amino acid sequence of SEQ ID NO: 11, and a LCDR3 comprising the amino acid sequence of SEQ ID NO: 12;

wherein the first linker comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20; and

wherein the second linker comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20.

2 . The protein of claim 1 ,

wherein the anti-PD-L1 VH domain comprises the amino acid sequence of SEQ ID NO: 21, and the anti-PD-L1 VL domain comprises the amino acid sequence of SEQ ID NO: 22; and

wherein the anti-CD47 VH domain comprises the amino acid sequence of SEQ ID NO: 23, and the anti-CD47 VL domain comprises the amino acid sequence of SEQ ID NO: 24.

3 . The protein of claim 1 ,

wherein the heavy chain comprises the amino acid sequence of SEQ ID NO: 25; and

wherein the light chain comprises the amino acid sequence of SEQ ID NO: 26.

4 . The protein of claim 1 , wherein the immunoglobulin heavy chain constant region is an IgG, IgE, IgM, IgD, IgA, or IgY constant region.

5 . The protein of claim 1 , wherein the immunoglobulin heavy chain constant region is an IgG1, IgG2, IgG3, IgG4, IgA1 or IgA2 constant region.

6 . The protein of claim 1 , wherein the immunoglobulin heavy chain constant region is immunologically inert.

7 . The protein of claim 1 , wherein the immunoglobulin heavy chain constant region is a wild-type human IgG1 constant region, a human IgG1 constant region comprising the amino acid substitutions L234A, L235A and G237A, a wild-type human IgG2 constant region, a wild-type human IgG4 constant region, or a human IgG4 constant region comprising the amino acid substitution S228P, wherein numbering is according to the EU index as in Kabat.

8 . The protein of claim 1 , wherein the first linker comprises the amino acid sequence of SEQ ID NO: 13.

9 . The protein of claim 1 , wherein the second linker comprises the amino acid sequence of SEQ ID NO: 14.

10 .- 12 . (canceled)

13 . A pharmaceutical composition comprising the protein of claim 1 , and a pharmaceutically acceptable carrier, diluent or excipient.

14 .- 19 . (canceled)

20 . A method for treating cancer in a subject, the method comprising administering to the subject a therapeutically effective amount of the protein of claim 1 .

21 . (canceled)

22 . The method of claim 20 , wherein the cancer is gastrointestinal stromal cancer (GIST), pancreatic cancer, skin cancer, melanoma, breast cancer, lung cancer, bronchial cancer, colorectal cancer, prostate cancer, stomach cancer, ovarian cancer, urinary bladder cancer, brain cancer, central nervous system cancer, peripheral nervous system cancer, esophageal cancer, cervical cancer, uterine cancer, endometrial cancer, cancer of the oral cavity or pharynx, liver cancer, kidney cancer, renal cell carcinoma, testicular cancer, biliary tract cancer, small bowel cancer, appendix cancer, salivary gland cancer, thyroid cancer, adrenal gland cancer, osteosarcoma, chondrosarcoma, or cancer of hematological tissues.

23 .- 30 . (canceled)

31 . The protein of claim 1 , wherein the the anti-PD-L1 VH domain comprises the amino acid sequence of SEQ ID NO: 21, and the anti-PD-L1 VL domain comprises the amino acid sequence of SEQ ID NO: 22.

32 . The protein of claim 1 , wherein the anti-CD47 VH domain comprises the amino acid sequence of SEQ ID NO: 23, and the anti-CD47 VL domain comprises the amino acid sequence of SEQ ID NO: 24.

33 . The protein of claim 1 , wherein the heavy chain comprises an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 25.

34 . The protein of claim 1 , wherein the light chain comprises an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 26.

35 . The protein of claim 1 , wherein the heavy chain comprises an amino acid sequence encoded by a nucleic acid having at least 90% sequence identity to the nucleic acid sequence of SEQ ID NO: 27.

36 . The protein of claim 1 , wherein the light chain comprises an amino acid sequence encoded by a nucleic acid having at least 90% sequence identity to the nucleic acid sequence of SEQ ID NO: 28.

37 . The protein of claim 1 , wherein the first linker or the second linker is a cleavable linker and wherein the cleavable linker is cleavable by a protease.

38 . The protein of claim 37 , wherein the protease is a MMP or a cathepsin.