Activatable antibodies that bind epidermal growth factor receptor and methods of use thereof
The invention relates generally to activatable antibodies that include a masking moiety (MM), a cleavable moiety (CM), and an antibody (AB) that specifically binds to epidermal growth factor receptor (EGFR), and to methods of making and using these anti-EGFR activatable antibodies in a variety of therapeutic, diagnostic and prophylactic indications.
1. A method of detecting presence or absence of a cleaving agent and Epidermal Growth Factor Receptor (EGFR) in a subject or a sample, the method comprising:
(a) contacting a subject or sample with an anti-EGFR activatable antibody, wherein the anti-EGFR activatable antibody in an activated state binds Epidermal Growth Factor Receptor (EGFR), and
(b) measuring a level of activated anti-EGFR activatable antibody in the subject or sample,
wherein a detectable level of activated anti-EGFR activatable antibody in the subject or sample indicates that the cleaving agent and EGFR are present in the subject or sample, and
wherein no detectable level of activated anti-EGFR activatable antibody in the subject or sample indicates that the cleaving agent, EGFR or both the cleaving agent and EGFR are absent in the subject or sample,
wherein the anti-EGFR activatable antibody comprises
an antibody or an antigen binding fragment thereof (AB) that specifically binds to EGFR, wherein the AB comprises (i) a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 26, SEQ ID NO: 30 and SEQ ID NO: 34 and a light chain amino acid sequence comprising SEQ ID NO: 68, or (ii) a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 6 and SEQ ID NO: 10 and a light chain amino acid sequence comprising SEQ ID NO: 68;
a masking moiety (MM) that inhibits the binding of the AB of the activatable antibody in an uncleaved state to EGFR, wherein the masking moiety comprises the amino acid sequence CISPRGCPDGPYVMY (SEQ ID NO: 14); and
a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease, and wherein the CM comprises the amino acid sequence LSGRSDNH (SEQ ID NO: 13),
wherein the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM.
2. The method of claim 1 , wherein the anti-EGFR activatable antibody comprises a detectable label.
3. The method of claim 2 , wherein the detectable label comprises a diagnostic agent, an imaging agent, a contrasting agent, an enzyme, a fluorescent label, a chromophore, a dye, one or more metal ions, or a ligand-based label.
4. The method of claim 1 , wherein the method is an in vivo method, an in situ method, an ex vivo method or in vitro method.
5. The method of claim 1 , wherein the antigen binding fragment thereof is selected from the group consisting of a Fab fragment, a F(ab′)2 fragment, a scFv, and a scAb.
6. The method of claim 1 , wherein the activatable antibody comprises a combination of heavy and light chains selected from the group consisting of:
(a) a heavy chain comprising amino acid sequence of SEQ ID NO: 26 and a light chain comprising the amino acid sequence of SEQ ID NO: 28;
(b) a heavy chain comprising amino acid sequence of SEQ ID NO: 2 and a light chain comprising the amino acid sequence of SEQ ID NO: 4;
(c) a heavy chain comprising amino acid sequence of SEQ ID NO: 6 and a light chain comprising the amino acid sequence of SEQ ID NO: 4;
(d) a heavy chain comprising amino acid sequence of SEQ ID NO 30 and a light chain comprising the amino acid sequence of SEQ ID NO: 28;
(e) a heavy chain comprising amino acid sequence of SEQ ID NO: 10 and a light chain comprising the amino acid sequence of SEQ ID NO: 4; and
(f) a heavy chain comprising amino acid sequence of SEQ ID NO: 34 and a light chain comprising the amino acid sequence of SEQ ID NO: 28.
7. The method of claim 1 , wherein the activatable antibody comprises a heavy chain comprising amino acid sequence of SEQ ID NO: 26 and a light chain comprising the amino acid sequence of SEQ ID NO: 28.
8. The method of claim 1 , wherein the activatable antibody comprises a heavy chain comprising amino acid sequence of SEQ ID NO: 30 and a light chain comprising the amino acid sequence of SEQ ID NO: 28.
9. The method of claim 1 , wherein the activatable antibody comprises a heavy chain comprising amino acid sequence of SEQ ID NO: 34 and a light chain comprising the amino acid sequence of SEQ ID NO: 28.
10. The method of claim 1 , wherein the AB has an equilibrium dissociation constant of about 100 nM or less for binding to EGFR.
11. The method of claim 1 , wherein the MM has an equilibrium dissociation constant for binding to the AB which is greater than the equilibrium dissociation constant of the AB to EGFR.
12. The method of claim 1 , wherein the MM does not interfere or compete with the AB of the activatable antibody in a cleaved state for binding to EGFR.
13. The method of claim 1 , wherein the MM is a polypeptide of no more than 40 amino acids in length.
14. The method of claim 1 , wherein the MM polypeptide sequence is different from that of EGFR and wherein the MM polypeptide sequence is no more than 50% identical to any natural binding partner of the AB.
15. The method of claim 1 , wherein the MM does not comprise more than 25% amino acid sequence identity to EGFR.
16. The method of claim 1 , wherein the MM does not comprise more than 10% amino acid sequence identity to EGFR.
17. The method of claim 1 , wherein the CM is a polypeptide of up to 15 amino acids in length.
18. The method of claim 1 , wherein the protease is co-localized with EGFR in a tissue, and wherein the protease cleaves the CM in the activatable antibody when the activatable antibody is exposed to the protease.
19. The method of claim 1 , wherein the activatable antibody comprises a linking peptide between the MM and the CM.
20. The method of claim 1 , wherein the activatable antibody comprises a linking peptide between the CM and the AB.
21. The method of claim 1 , wherein the activatable antibody comprises a first linking peptide (LP1) and a second linking peptide (LP2), and wherein the activatable antibody in an uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-LP1-CM-LP2-AB or AB-LP2-CM-LP1-MM.
22. The method of claim 21 , wherein the two linking peptides are not identical to each other.
23. The method of claim 21 , wherein at least one of LP1 or LP2 comprises an amino acid sequence selected from the group consisting of (GS)n, (GGS)n, (GSGGS)n (SEQ ID NO: 15) and (GGGS)n (SEQ ID NO: 16), where n is an integer of at least one.
24. The method of claim 21 , wherein at least one of LP1 or LP2 comprises an amino acid sequence selected from the group consisting of GGSG (SEQ ID NO: 17), GGSGG (SEQ ID NO: 18), GSGSG (SEQ ID NO: 19), GSGGG (SEQ ID NO: 20), GGGSG (SEQ ID NO: 21), and GSSSG (SEQ ID NO: 22).
25. The method of claim 21 , wherein LP1 comprises the amino acid sequence GSSGGSGGSGGSG (SEQ ID NO: 23).
26. The method of claim 21 , wherein LP2 comprises the amino acid sequence GSSGT (SEQ ID NO: 24) or GSSG (SEQ ID NO: 37).
27. The method of claim 1 , wherein the activatable antibody in an uncleaved state comprises a spacer, wherein the spacer is joined directly to the MM and has the structural arrangement from N-terminus to C-terminus of spacer-MM-CM-AB.
28. The method of claim 27 , wherein the spacer comprises the amino acid sequence QGQSGQ (SEQ ID NO: 38).
29. The method of claim 27 , wherein the spacer and MM comprises the amino acid sequence QGQSGQCISPRGCPDGPYVMY (SEQ ID NO: 59).
30. The method of claim 1 , wherein the AB is conjugated to an agent.
31. The method of claim 30 , wherein the agent is a toxin or a fragment thereof.
32. The method of claim 30 , wherein the agent is a dolastatin or a derivative thereof.
33. The method of claim 30 , wherein the agent is an auristatin or a derivative thereof.
34. The method of claim 30 , wherein the agent is auristatin E or a derivative thereof.
35. The method of claim 30 , wherein the agent is monomethyl auristatin E (MMAE).
36. The method of claim 30 , wherein the agent is a maytansinoid or a derivative thereof.
37. The method of claim 30 , wherein the agent is DM1 or DM4.
38. The method of claim 30 , wherein the agent is a duocarmycin or a derivative thereof.
39. The method of claim 30 , wherein the agent is a calicheamicin or a derivative thereof.
40. The method of claim 30 , wherein the agent is conjugated to the AB via a linker.
41. The method of claim 40 , wherein the linker is a cleavable linker.
42. The method of claim 1 , wherein the MM has a dissociation constant for binding to the AB which is no more than the dissociation constant of the AB to EGFR.
43. The method of claim 1 , wherein the binding of the AB to EGFR is not inhibited when the activatable antibody is in a cleaved state.
44. The method of claim 21 , wherein LP1 comprises the amino acid sequence GSSGGSGGSGGSG (SEQ ID NO: 23) and LP2 comprises the amino acid sequence GSSGT (SEQ ID NO: 24) or GSSG (SEQ ID NO: 37), and wherein the AB comprises a heavy chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 26, and a light chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 68.
45. The method of claim 21 , wherein LP1 comprises the amino acid sequence GSSGGSGGSGGSG (SEQ ID NO: 23) and LP2 comprises the amino acid sequence GSSGT (SEQ ID NO: 24) or GSSG (SEQ ID NO: 37), and wherein the AB comprises a heavy chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 30, and a light chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 68.
46. The method of claim 21 , wherein LP1 comprises the amino acid sequence GSSGGSGGSGGSG (SEQ ID NO: 23) and LP2 comprises the amino acid sequence GSSGT (SEQ ID NO: 24) or GSSG (SEQ ID NO: 37), and wherein the AB comprises a heavy chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 34, and a light chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 68.
47. The method of claim 1 , wherein the AB comprises a heavy chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 26, and a light chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 68.
48. The method of claim 1 , wherein the AB comprises a heavy chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 30, and a light chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 68.
49. The method of claim 1 , wherein the AB comprises a heavy chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 34, and a light chain amino acid sequence comprising the amino acid sequence of SEQ ID NO: 68.
50. The method of claim 1 , wherein the activatable antibody is conjugated to an agent.
51. The method of claim 50 , wherein the activatable antibody is conjugated to the agent via a linker.
52. The method of claim 51 , wherein the linker is a cleavable linker.