ANTI-CEA AND ANTI-CD137 MULTISPECIFIC ANTIBODIES AND METHODS OF USE

1 . A multispecific antibody or antigen-binding fragment thereof, comprising a first antigen binding domain that specifically binds to human CEA at amino acids 596 to 674 of SEQ ID NO:88 and a second antigen binding domain that specifically binds to human CD137.

2 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the first antigen binding domain does not bind to other CEACAM family members.

3 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the first antigen binding domain that specifically binds to human CEA comprises:

(i) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 7, (b) a HCDR2 of SEQ ID NO:8, and (c) a HCDR3 of SEQ ID NO:9; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO: 10, (e) a LCDR2 of SEQ ID NO: 11, and (f) a LCDR3 of SEQ ID NO:6;

(ii) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:24, (b) a HCDR2 of SEQ ID NO:25, and (c) a HCDR3 of SEQ ID NO:26; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO:27, (e) a LCDR2 of SEQ ID NO:28, and (f) a LCDR3 of SEQ ID NO: 23; or

(iii) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:41, (b) a HCDR2 of SEQ ID NO:42, and (c) a HCDR3 of SEQ ID NO:43; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO:44, (e) a LCDR2 of SEQ ID NO:45, and (f) a LCDR3 of SEQ ID NO:40.

4 . The multispecific antibody or antigen-binding fragment thereof of claim 3 , wherein the first antigen binding domain that specifically binds to human CEA comprises:

(i) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 14, and a light chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 15;

(ii) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 31, and a light chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 32; or

(iii) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 48, and a light chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 49.

5 . (canceled)

6 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the first antigen binding domain that specifically binds to human CEA comprises:

(i) a heavy chain variable region that comprises SEQ ID NO:14, and a light chain variable region that comprises SEQ ID NO: 15;

(ii) a heavy chain variable region that comprises SEQ ID NO: 31, and a light chain variable region that comprises SEQ ID NO: 32; or

(iii) a heavy chain variable region that comprises SEQ ID NO: 48, and a light chain variable region that comprises SEQ ID NO: 49.

7 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the second antigen binding domain that specifically binds to human CD137 comprises:

(i) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 65, (b) a HCDR2 of SEQ ID NO:80, and (c) a HCDR3 of SEQ ID NO:81;

(ii) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:65, (b) a HCDR2 of SEQ ID NO:73, and (c) a HCDR3 of SEQ ID NO:67;

(iii) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:65, (b) a HCDR2 of SEQ ID NO:66, and (c) a HCDR3 of SEQ ID NO:67; or

(iv) a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:55, (b) a HCDR2 of SEQ ID NO:56, and (c) a HCDR3 of SEQ ID NO:57.

8 . The multispecific antibody or antigen-binding fragment thereof of claim 7 , wherein the second antigen binding domain that specifically binds to human CD137 comprises:

(i) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO:84;

(ii) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 86;

(iii) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO:75;

(iv) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO:70; or

(v) a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO:60.

9 . (canceled)

10 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the second antigen binding domain that specifically binds to human CD137 comprises:

(i) a heavy chain variable region that comprises SEQ ID NO:84;

(ii) a heavy chain variable region that comprises SEQ ID NO: 86;

(iii) a heavy chain variable region that comprises SEQ ID NO: 75;

(iv) a heavy chain variable region that comprises SEQ ID NO: 70; or

(v) a heavy chain variable region that comprises SEQ ID NO: 60.

11 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein:

(i) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 7, (b) a HCDR2 of SEQ ID NO:8, and (c) a HCDR3 of SEQ ID NO:9; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO: 10, (e) a LCDR2 of SEQ ID NO: 11, and (f) a LCDR3 of SEQ ID NO:6; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 65, (b) a HCDR2 of SEQ ID NO:80, and (c) a HCDR3 of SEQ ID NO:81 and;

(ii) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:7, (b) a HCDR2 of SEQ ID NO:8, and (c) a HCDR3 of SEQ ID NO:9; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO:10, (e) a LCDR2 of SEQ ID NO:11, and (f) a LCDR3 of SEQ ID NO: 6; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 65, (b) a HCDR2 of SEQ ID NO:73, and (c) a HCDR3 of SEQ ID NO:67;

(iii) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:7, (b) a HCDR2 of SEQ ID NO:8, and (c) a HCDR3 of SEQ ID NO:9; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO:10, (e) a LCDR2 of SEQ ID NO:11, and (f) a LCDR3 of SEQ ID NO:6; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 65, (b) a HCDR2 of SEQ ID NO:66, and (c) a HCDR3 of SEQ ID NO:67; or

(iv) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO: 7, (b) a HCDR2 of SEQ ID NO:8, and (c) a HCDR3 of SEQ ID NO:9; and a light chain variable region that comprises: (d) a LCDR1 of SEQ ID NO:10, (e) a LCDR2 of SEQ ID NO:11, and (f) a LCDR3 of SEQ ID NO:6; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises (a) a HCDR1 of SEQ ID NO:55, (b) a HCDR2 of SEQ ID NO:56, and (c) a HCDR3 of SEQ ID NO:57.

12 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein:

(i) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises SEQ ID NO:14, and a light chain variable region that comprises SEQ ID NO: 15; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises SEQ ID NO:84;

(ii) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises SEQ ID NO:14, and a light chain variable region that comprises SEQ ID NO: 15; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises SEQ ID NO:86;

(iii) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises SEQ ID NO:14, and a light chain variable region that comprises SEQ ID NO: 15; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises SEQ ID NO:75;

(iv) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises SEQ ID NO:14, and a light chain variable region that comprises SEQ ID NO: 15; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises SEQ ID NO:70; or

(v) the first antigen binding domain that specifically binds to human CEA comprises: a heavy chain variable region that comprises SEQ ID NO:14, and a light chain variable region that comprises SEQ ID NO: 15; and the second antigen binding domain that specifically binds to human CD137 comprises: a heavy chain variable region that comprises SEQ ID NO:60.

13 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the multispecific antibody or antigen-binding fragment thereof is a monoclonal antibody, a chimeric antibody, a humanized antibody, a human engineered antibody, a single chain antibody (scFv), a Fab fragment, a Fab′ fragment, or a F(ab′)2 fragment.

14 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the multispecific antibody or antigen-binding fragment thereof is a bispecific antibody.

15 . The multispecific antibody or antigen-binding fragment thereof of claim 14 , wherein the bispecific antibody comprises a linker selected from SEQ ID NO:317 to SEQ ID NO: 358.

16 . The multispecific antibody or antigen-binding fragment thereof of claim 15 , wherein the linker is SEQ ID NO: 324 or SEQ ID NO: 329.

17 . (canceled)

18 . The multispecific antibody or antigen-binding fragment thereof of claim 14 , wherein the bispecific antibody is BE-146 (SEQ ID NO: 313 and SEQ ID NO: 179), BE-189 (SEQ ID NO: 255 and SEQ ID NO: 179), BE-718 (SEQ ID NO: 295 and SEQ ID NO: 179), BE-740 (SEQ ID NO: 297 and SEQ ID NO: 179), BE-942 (SEQ ID NO: 299, SEQ ID NO: 301, and SEQ ID NO:303), BE-755 (SEQ ID NO: 299, SEQ ID NO: 301, and SEQ ID NO: 305), BE-562 (SEQ ID NO: 307 and SEQ ID NO: 179), BE-375 (SEQ ID NO: 309 and SEQ ID NO: 179), or BE-244 (SEQ ID NO: 311 and SEQ ID NO: 179).

19 .- 26 . (canceled)

27 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the antibody or antigen-binding fragment thereof has one or more of the following: antibody dependent cellular cytotoxicity (ADCC), complement dependent cytotoxicity (CDC), reduced glycosylation, no glycosylation, hypofucosylation, or increased bisecting GlcNac structures.

28 .- 29 . (canceled)

30 . The multispecific antibody or antigen-binding fragment thereof of claim 1 , wherein the Fc domain is an IgG1 with reduced effector function or an IgG4.

31 . (canceled)

32 . A pharmaceutical composition comprising the multispecific antibody or antigen-binding fragment thereof of claim 1 and a pharmaceutically acceptable carrier.

33 . (canceled)

34 . A method of treating cancer comprising administering to a patient in need an effective amount of the multispecific antibody or antigen-binding fragment thereof of claim 1 .

35 .- 46 . (canceled)

47 . An isolated nucleic acid that encodes the multispecific antibody or antigen-binding fragment thereof of claim 1 .

48 . A vector comprising the nucleic acid of claim 47 .

49 . A host cell comprising the nucleic acid of claim 47 .

50 . A process for producing a multispecific antibody or antigen-binding fragment thereof comprising cultivating the host cell of claim 49 and recovering the antibody or antigen-binding fragment thereof from the culture.