Antagonist antibodies against human immune checkpoint CEACAM1 (CD66a) and formulations, kits, and methods of use thereof

1. An antibody or antigen-binding fragment thereof that specifically binds human CEACAM1, said antibody or antigen-binding fragment thereof comprising:

(a) a heavy chain variable region comprising:

(SEQ ID NO: 13)

GYIFRNYGMN

(SEQ ID NO: 14)

WINTYTGEPTYADDFKG,

and

(SEQ ID NO: 15)

RGWLLTGGAMDY;

and

a light chain variable region comprising:

(SEQ ID NO: 16)

RASQDIGSSLN,

(SEQ ID NO: 17)

ATSSLDS,

and

(SEQ ID NO: 18)

LQYVSSPWT;

(b) a heavy chain variable region comprising:

(SEQ ID NO: 19)

GYIFRNYGMN,

(SEQ ID NO: 20)

WINTYTGEPTYADDFKG,

and

(SEQ ID NO: 21)

DCGTSHYYAMDY;

and

a light chain variable region comprising:

(SEQ ID NO: 22)

RASQDISNYLN,

and

(SEQ ID NO: 23)

YTSRLHS,

and

(SEQ ID NO: 24)

QQGNTFPLT;

or

(c) a heavy chain variable region comprising:

(SEQ ID NO: 25)

GYAFTIYLIE,

(SEQ ID NO: 26)

VINPGSGGTNYNEKFKG,

and

(SEQ ID NO: 27)

SYYYGSFAMDY;

a light chain variable region comprising:

(SEQ ID NO: 28)

RASQDIGNYLN,

(SEQ ID NO: 29)

YTSRLHS,

and

(SEQ ID NO: 30)

QQGNTLRT.

2. The isolated antibody or antigen-binding fragment thereof of claim 1 , wherein said antibody or antigen-binding fragment comprises:

(a) a heavy chain variable region comprising SEQ ID NO:2; and

a light chain variable region comprising SEQ ID NO:4;

(b) a heavy chain variable region comprising SEQ ID NO:6; and

a light chain variable region comprising SEQ ID NO:8; or

(c) a heavy chain variable region comprising SEQ ID NO:10; and

a light chain variable region comprising SEQ ID NO: 12.

3. The antibody or antigen-binding fragment thereof of claim 1 , wherein said antibody or antigen-binding fragment thereof comprises a human framework region.

4. The antibody or antigen-binding fragment thereof of claim 1 , wherein said antibody or antigen-binding fragment thereof comprises an Fc region.

5. The antibody or antigen-binding fragment thereof of claim 1 , wherein said antibody or antigen-binding fragment is selected from the group consisting of chimeric, humanized, and monoclonal.

6. The antibody or antigen-binding fragment thereof of claim 1 , wherein said antigen-binding fragment thereof is selected from the group consisting of sdAb, Fv, disulfide-linked Fv, scFv, diabody, Fd, Fab, Fab′, and F(ab′)2.

7. A conjugated antibody or antigen-binding fragment thereof comprising the antibody or antigen-binding fragment thereof of claim 1 , linked or conjugated to a therapeutic agent, an imaging agent, or a detectable marker.

8. The antibody or antigen-binding fragment thereof of claim 7 , wherein said therapeutic agent is selected from the group consisting of a cytotoxic drug, a radioactive isotope, an immunomodulator, and a second antibody.

9. A method of inhibiting human CEACAM1 expression or activity in a subject in need thereof comprising administering to said subject a therapeutically effective amount of an antibody or antigen-binding fragment thereof of claim 1 .

10. The method of claim 9 , wherein said subject has is a hematologic malignancy, or a solid tumor selected from the group consisting of head and neck squamous cell carcinoma, kidney renal clear cell carcinoma, kidney renal papillary cell carcinoma, brain lower grade glioma, pancreatic, colorectal, stomach, melanoma, liver, bile duct, urinary tract, lung, lymphoma, upper aerodigestive, breast, thyroid, esophageal, and ovarian cancer.

11. The method of claim 9 , wherein said subject is receiving or has received an anti-PD-I or anti-PD-LI or anti-CTLA4 therapy.

12. A pharmaceutical formulation comprising an antibody or antigen-binding fragment thereof of claim 1 and a carrier and/or excipient.