Constructs targeting AFP peptide/MHC complexes and uses thereof

Patent metadata

Field	Value
Publication number	US-10011658-B2
Application number	US-201715829783-A
Country	US
Kind code	B2
Filing date	Dec 1, 2017
Priority date	Apr 3, 2015
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

The present application provides constructs comprising an antibody moiety that specifically binds to a complex comprising an AFP peptide and an MHC class I protein. Also provided are methods of making and using these constructs.

First claim

What is claimed is:

1. An isolated anti-AMC construct comprising an antibody moiety that specifically binds to a complex comprising an alpha-fetoprotein (AFP) peptide and a major histocompatibility (MHC) class I protein (AFP/MHC class I complex, or AMC), wherein the AFP peptide comprises the amino acid sequence of SEQ ID NO: 4, wherein the MHC class I protein is HLA-A02, and wherein the antibody moiety comprises:
a heavy chain variable domain comprising a heavy chain complementarity determining region (HC-CDR)1 comprising the amino acid sequence of SEQ ID NO: 63, an HC-CDR2 comprising the amino acid sequence of SEQ ID NO: 73, and an HC-CDR3 comprising the amino acid sequence of SEQ ID NO: 83; and
a light chain variable domain comprising a light chain complementarity determining region (LC-CDR)1 comprising the amino acid sequence of SEQ ID NO: 96, an LC-CDR2 comprising the amino acid sequence of SEQ ID NO: 106, and an LC-CDR3 comprising the amino acid sequence of SEQ ID NO: 116.

2. The isolated anti-AMC construct of claim 1 , wherein the heavy chain variable domain comprises the amino acid sequence of SEQ ID NO: 23 and the light chain variable domain comprises the amino acid sequence of SEQ ID NO: 33.

3. The isolated anti-AMC construct of claim 1 , wherein the isolated anti-AMC construct is a chimeric antigen receptor (CAR) comprising an extracellular domain comprising the antibody moiety, a transmembrane domain, and an intracellular signaling domain capable of activating an immune cell.

4. The isolated anti-AMC construct of claim 3 , wherein the intracellular signaling domain comprises a CD3ζ intracellular signaling sequence and a co-stimulatory signaling sequence.

5. The isolated anti-AMC construct of claim 4 , wherein the co-stimulatory signaling sequence comprises a CD28 or 4-1BB intracellular signaling sequence.

6. The isolated anti-AMC construct of claim 5 , wherein the co-stimulatory signaling sequence comprises a CD28 intracellular signaling sequence.

7. The isolated anti-AMC construct of claim 6 , wherein the transmembrane domain comprises a CD28 transmembrane region.

8. The isolated anti-AMC construct of claim 3 , wherein the antibody moiety is an scFv.

9. The isolated anti-AMC construct of claim 1 , wherein the isolated anti-AMC construct is a tandem scFv comprising a first scFv linked by a peptide linker to a second scFv, wherein the first scFv is the antibody moiety that specifically binds to the AFP/MHC class I complex.

10. The isolated anti-AMC construct of claim 9 , wherein the second scFv is specific for CD3ε.

11. The isolated anti-AMC construct of claim 10 , wherein the first scFv is N-terminal to the second scFv.

12. The isolated anti-AMC construct of claim 1 , wherein the isolated anti-AMC construct is an immunoconjugate comprising the antibody moiety and an effector molecule, wherein the effector molecule is a therapeutic agent selected from the group consisting of a drug, a toxin, a radioisotope, a protein, a peptide, and a nucleic acid.

13. The isolated anti-AMC construct of claim 1 , wherein the isolated anti-AMC construct is an immunoconjugate comprising the antibody moiety and a label.

14. A nucleic acid encoding the polypeptide components of the isolated anti-AMC construct of claim 1 .

15. A host cell expressing the isolated anti-AMC construct of claim 1 .

16. An effector cell expressing the isolated anti-AMC construct of claim 1 .

17. A CAR T cell expressing the isolated anti-AMC construct of claim 3 , wherein the intracellular signaling domain is capable of activating a T cell.

18. A pharmaceutical composition comprising the CART cell of claim 17 .

19. A method of treating an individual having an AFP-positive cancer, comprising administering to the individual an effective amount of the pharmaceutical composition of claim 18 , wherein the cancer expresses human AFP and HLA-A02.

20. The method of claim 19 , wherein the administration is via intravenous or intratumoral route.

21. The method of claim 19 , wherein the cancer is hepatocellular carcinoma, germ cell tumor, or breast cancer.

22. The method of claim 21 , wherein the cancer is hepatocellular carcinoma.

23. The method of claim 22 , wherein the cancer is metastatic hepatocellular carcinoma.

24. The isolated anti-AMC construct of claim 1 , wherein the MHC class I protein is the HLA-A*02:01 subtype of the HLA-A02 allele.

Assignees

• Eureka Therapeutics Inc

Inventors

• Liu Cheng
• Liu Hong
• Xu Yiyang
• Xiang Jingyi
• Long Li

Classifications

• A61P35/00

  Antineoplastic agents · CPC title

• A61P35/04

  specific for metastasis · CPC title

• A61P1/16

  for liver or gallbladder disorders, e.g. hepatoprotective agents, cholagogues, litholytics · CPC title

• A61P15/00

  Drugs for genital or sexual disorders (for disorders of sex hormones A61P5/24); Contraceptives · CPC title

• C07K2317/92

  Affinity (KD), association rate (Ka), dissociation rate (Kd) or EC50 value · CPC title