Anti-cd71 antibodies, activatable anti-cd71 antibodies, and methods of use thereof

Patent metadata

Field	Value
Publication number	US-2016355599-A1
Application number	US-201615146294-A
Country	US
Kind code	A1
Filing date	May 4, 2016
Priority date	May 4, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

The invention relates generally to antibodies that bind CD71, activatable antibodies that specifically bind to CD71 and methods of making and using these anti-CD71 antibodies and anti-CD71 activatable antibodies in a variety of therapeutic, diagnostic and prophylactic indications.

First claim

1 . An isolated antibody or an antigen binding fragment thereof (AB) that specifically binds to mammalian CD71, wherein the AB specifically binds human CD71 and cynomolgus monkey CD71.

2 . The AB of claim 1 , wherein the AB comprises the VH CDR1 sequence GYTFTSYWMH (SEQ ID NO: 9); the VH CDR2 sequence AIYPGNSETG (SEQ ID NO: 10); the VH CDR3 sequence ENWDPGFAF (SEQ ID NO: 11); the VL CDR1 sequence SASSSVYYMY (SEQ ID NO: 12) or CRASSSVYYMY (SEQ ID NO: 13); the VL CDR2 sequence STSNLAS (SEQ ID NO: 14); and the VL CDR3 sequence QQRRNYPYT (SEQ ID NO: 15).

3 . The AB of claim 1 , wherein the AB comprises a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 3-5, and a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 6-8.

4 . An isolated antibody or antigen binding fragment thereof that binds to the same epitope on human CD71 and/or cynomolgus monkey CD71 as the AB of claim 2 .

5 . An isolated antibody or antigen binding fragment thereof that cross-competes with the AB of claim 2 for binding to human CD71 and/or cynomolgus monkey CD71.

6 . An activatable antibody that, in an activated state, specifically binds to mammalian CD71 comprising:
an antibody or an antigen binding fragment thereof (AB) that specifically binds to mammalian CD71, wherein the AB specifically binds human CD71 and cynomolgus monkey CD71; a masking moiety (MM) coupled to the AB that inhibits the binding of the AB to CD71 when the activatable antibody is in an uncleaved state; and a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease.

7 . The activatable antibody of claim 6 , wherein the MM has one or more of the characteristics selected from the group consisting of:
(i) the MM has a dissociation constant for binding to the AB that is greater than the dissociation constant of the AB to CD71; (ii) the MM does not interfere or compete with the AB for binding to CD71 when the activatable antibody is in a cleaved state; (iii) the MM is a polypeptide of no more than 40 amino acids in length; (iv) the MM polypeptide sequence is different from that of human CD71; (v) the MM polypeptide sequence is no more than 50% identical to any natural binding partner of the AB; and (vi) the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 16-295 and 297-314.

8 .- 13 . (canceled)

14 . The activatable antibody of claim 6 , wherein the CM has one or more of the characteristics selected from the group consisting of:
(i) the CM is a substrate for a protease that is active in diseased tissue; and (ii) the CM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 356-423, 680-698, 713, 714, and 789-808.

15 .- 16 . (canceled)

17 . The activatable antibody of claim 6 , wherein the antigen binding fragment thereof is selected from the group consisting of a Fab fragment, a F(ab′) 2 fragment, a scFv, a scAb, a dAb, a single domain heavy chain antibody, and a single domain light chain antibody.

18 . (canceled)

19 . The activatable antibody of claim 6 , wherein AB has one or more of the characteristics selected from the group consisting of:
(i) the AB comprises the VH CDR1 sequence GYTFTSYWMH (SEQ ID NO: 9); the VH CDR2 sequence AIYPGNSETG (SEQ ID NO: 10); the VH CDR3 sequence ENWDPGFAF (SEQ ID NO: 11); the VL CDR1 sequence SASSSVYYMY (SEQ ID NO: 12) or CRASSSVYYMY (SEQ ID NO: 13); the VL CDR2 sequence STSNLAS (SEQ ID NO: 14); and the VL CDR3 sequence QQRRNYPYT (SEQ ID NO: 15); and (ii) the AB comprises a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 3-5, and a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 6-8.

20 . (canceled)

21 . The activatable antibody of claim 6 , wherein the AB is linked to the CM.

22 . The activatable antibody of claim 6 , wherein the AB is linked directly to the CM.

23 . The activatable antibody of claim 6 , wherein the AB is linked to the CM via a linking peptide.

24 . The activatable antibody of claim 6 , wherein the MM is linked to the CM such that the activatable antibody in an uncleaved state comprises the structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM.

25 . The activatable antibody of claim 6 , wherein the activatable antibody comprises a linking peptide between the MM and the CM, a linking peptide between the CM and the AB, or both a linking peptide between the MM and the CM and a linking peptide between the CM and the AB.

26 . (canceled)

27 . The activatable antibody of claim 6 , wherein the activatable antibody comprises a first linking peptide (LP1) and a second linking peptide (LP2), and wherein the activatable antibody in the 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.

28 . The activatable antibody of claim 27 , wherein the two linking peptides are not identical to each other.

29 . The activatable antibody of claim 27 , wherein each of LP1 and LP2 is a peptide of about 1 to 20 amino acids in length.

30 . The activatable antibody of claim 6 , wherein the activatable antibody has one or more of the characteristics selected from the group consisting of:
(a) the activatable antibody comprises the heavy chain sequence of SEQ ID NO: 325 or 699 and a light chain comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 327, 329, 331, 333, 335, 337, 650, 652, 654, 656, 658, 660, 670-673, 701-712, and 721-788; (b) the activatable antibody comprises a combination of amino acid sequences, wherein the combination of amino acid sequences is selected from a single row in Table D, wherein for a given combination,
(i) the heavy chain of the AB comprises the amino acid sequences of the VH CDR sequences corresponding to the given combination in the single row listed in Table D,
(ii) the light chain of the AB comprises the amino acid sequences of the VL CDR sequences corresponding to the given combination in the single row listed in Table D,
(iii) the MM comprises the amino acid sequence of the mask sequence (MM) corresponding to the given combination in the single row listed in Table D, and
(iv) the CM comprises the amino acid sequence of the substrate sequence (CM) corresponding to the given combination in the single row listed in Table D;
(c) the activatable antibody comprises a combination of amino acid sequences, wherein for a given combination of amino acid sequences,
(i) the heavy chain of the AB comprises the amino acid sequences of the VH sequence or VH CDR sequences selected from the group consisting of: the VH sequence or VH CDR sequences listed in the corresponding column of Table E,
(ii) the light chain of the AB comprises the amino acid sequences of the VL sequence or VL CDR sequences selected from the group consisting of: the VL sequence or VL CDR sequences listed in the corresponding column of Table E,
(iii) the MM comprises the amino acid sequence of the mask sequence (MM) selected from the group consisting of: the MM sequences listed in the corresponding column of Table E, and
(iv) the CM comprises the amino acid sequence of the substrate sequence (CM) selected from the group consisting of: the C

Assignees

• Cytomx Therapeutics Inc

Inventors

• Sagert Jason Gary
• Tipton Kimberly Ann
• Terrett Jonathan Alexander
• Singh Shweta
• Weaver Annie Yang
• Desnoyers Luc Roland

Classifications

• C07K2317/94

  Stability, e.g. half-life, pH, temperature or enzyme-resistance · CPC title

• C07K16/2881 Primary

  against CD71 · CPC title

• C07K2317/33

  Crossreactivity, e.g. for species or epitope, or lack of said crossreactivity · CPC title

• C07K2319/50

  containing protease site · CPC title

• C07K2317/24

  containing regions, domains or residues from different species, e.g. chimeric, humanized or veneered · CPC title