Antibodies, pharmaceutical compositions and methods
Pharmaceutical composition comprising antibodies or antigen binding fragments thereof that bind to stage-specific embryonic antigen 4 (SSEA-4) are disclosed herein, as well as methods of use thereof. Methods of use include, without limitation, cancer therapies and diagnostics. The antibodies of the disclosure can bind to certain cancer cell surfaces. Exemplary targets of the antibodies disclosed herein can include carcinomas, such as breast cancer, lung cancer, esophageal cancer, rectal cancer, biliary cancer, liver cancer, buccal cancer, gastric cancer, colon cancer, nasopharyngeal cancer, kidney cancer, prostate cancer, ovarian cancer, cervical cancer, endometrial cancer, pancreatic cancer, testicular cancer, bladder cancer, head and neck cancer, oral cancer, neuroendocrine cancer, adrenal cancer, thyroid cancer, bone cancer, skin cancer, basal cell carcinoma, squamous cell carcinoma, melanoma, and/or brain tumor.
1. A humanized anti-SSEA-4 antibody comprising:
a heavy chain variable domain having the amino acid sequence of SEQ ID NO: 55, and
a light chain variable domain having the amino acid sequence of SEQ ID NO: 70.
2. A humanized anti-SSEA-4 antibody comprising:
(a) a heavy chain region, wherein the heavy chain region comprises three complementarity determining regions (CDRs), HCDR1, HCDR2, and HCDR3, having the amino acid sequences set forth in SEQ ID NOs: 67, 68 and 69, respectively; and
(b) a light chain region, wherein the light chain region comprises three complementarity determining regions (CDRs), LCDR1, LCDR2 and LCDR3, having the amino acid sequences set forth in SEQ ID NOs: 72, 73 and 74, respectively.
3. The humanized anti-SSEA-4 antibody of claim 2 , wherein the HCDR2 at least one of the following amino acid substitutions:
(a) amino acid residue 7 from N-terminal of HCDR2 (SEQ ID NO: 68) is substituted with a neutral amino acid, and/or
(b) amino acid residue 9 from N-terminal of HCDR2 (SEQ ID NO: 68) is substituted with a neutral amino acid.
4. The humanized anti-SSEA-4 antibody of claim 3 , wherein said amino acid residue 7 in said HCDR2 is substituted with a neutral amino acid selected from Serine (N56S) or Glutamine (N56Q).
5. The humanized anti-SSEA-4 antibody of claim 3 , wherein said amino acid residue 9 in said HCDR2 is substituted with a neutral amino acid selected from Tyrosine (N58Y).
6. The humanized anti-SSEA-4 antibody of claims 1 - 5 , wherein the humanized antibody binds to stage-specific embryonic antigen 4 (SSEA-4) with a Kd from 10 −6 to 10 −8 M or less, and wherein the Kd is measured by surface plasmon resonance or ELISA.
7. A pharmaceutical composition, comprising the humanized anti-SSEA-4 antibody of claims 1 - 5 ; and a pharmaceutical acceptable carrier.
8. The pharmaceutical composition of claim 7 , further comprising at least one additional therapeutic agent.
9. An antibody-drug conjugate (ADC) comprising a therapeutic agent and an anti-SSEA-4 antibody that binds SSEA-4, wherein the therapeutic agent is covalently conjugated to the antibody by a linker, wherein the anti-SSEA-4 antibody is selected from claims 1 - 5 .
10. A humanized bi-specific antibody of claims 1 - 5 , comprising a first binding domain that specifically binds SSEA-4 and a second binding domain that specifically binds to T cell surface antigens.
11. The humanized bi-specific antibody of claim 10 , wherein the T cell surface antigens comprising CD2, CD3, CD4, CDS, CD6, CD8, CD28, CD40L or CD44.
12. The humanized anti-SSEA-4 antibody of claims 1 - 5 , wherein the antibody further comprises a chimeric antigen receptor (CAR) domain specific for SSEA-4.
13. The humanized anti-SSEA-4 antibody of claim 12 , wherein the CAR domain comprises a transmembrane domain and a intracellular signaling domain, wherein the transmembrane domain comprises a sequence of the transmembrane domains of CD8 and/or CD28; and wherein the intracellular signaling domain comprises a sequence of the intracellular signaling domains of one or more of CD27, CD28, CD137, OX40, ICOS, 4-1BB, PD-1, CTLA-4, LAG-3, 2B4, BTLA and CD3zeta.