Antibodies and antibody-drug conjugates specific for cd123 and uses thereof

Abstract

The present invention provides antibodies that specifically bind to CD123. The invention further relates to immunoconjugates (e.g., antibody-drug conjugates, or ADCs) comprising such antibodies, antibody encoding nucleic acids, and methods of obtaining such antibodies. The invention further relates to therapeutic methods for use of these antibodies and ADCs for the treatment of a condition associated with cells expressing CD123 (e.g., cancer or autoimmune disease).

1 - 47 . (canceled) 
     
     
         48 . A method of treating a condition associated with cells expressing CD123 in a subject, the method comprising administering to the subject in need thereof an effective amount of an antibody-drug conjugate;
 wherein the antibody-drug conjugate comprises an antibody which specifically binds to CD123, a linker, and a cytotoxic agent;   wherein the antibody binds CD123 without inhibiting the IL-3 signaling pathway.   
     
     
         49 . The method of  claim 48 , wherein the antibody comprises:
 a heavy chain variable region (VH) comprising three complementarity determining regions (CDRs) of a VH comprising the amino acid sequence of SEQ ID NO: 6, 24, 32, or 44, and   a light chain variable region (VL) comprising three CDRs of a VL comprising the amino acid sequence of SEQ ID NO: 17, 28, 39, 48, 57, or 71.   
     
     
         50 . The method of  claim 49 , wherein at least one of the following applies:
 (a) the VH region of the antibody comprises
 (i) a VH CDR1 comprising the amino acid sequence of SEQ ID NO: 7 or 33; 
 (ii) a VH CDR2 comprising the amino acid sequence of SEQ ID NO: 8, 25, 34, or 45; and 
 (iii) a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 9, 35, or 46; 
   (b) the VL region of the antibody comprises:
 (i) a VL CDR1 comprising the amino acid sequence of SEQ ID NO: 18 or 40; 
 (ii) a VL CDR2 comprising the amino acid sequence of SEQ ID NO: 19 or 41; and 
 (iii) a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 20 or 42. 
   
     
     
         51 . The method of  claim 50 , wherein at least one of the following applies:
 (a) the VH of the antibody comprises
 (i) a VH CDR1 comprising the amino acid sequence of SEQ ID NO: 7, 
 (ii) a VH CDR2 comprising the amino acid sequence of SEQ ID NO: 25, and 
 (iii) a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 9; 
   (b) the VL of the antibody comprises
 (i) a VL CDR1 comprising the amino acid sequence of SEQ ID NO: 18, 
 (ii) a VL CDR2 comprising the amino acid sequence of SEQ ID NO: 19, and 
 (iii) a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 20. 
   
     
     
         52 . The method of  claim 49 , wherein at least one of the following applies:
 (a) the VH of the antibody comprises the amino acid sequence of SEQ ID NO: 24 or a variant thereof with one or several conservative amino acid substitutions in residues that are not within a CDR;   (b) the VL of the antibody comprises the amino acid sequence shown in SEQ ID NO: 28 or a variant thereof with one or several amino acid substitutions in amino acids that are not within a CDR.   
     
     
         53 . The method of  claim 50 , wherein the antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 30 and a heavy chain comprising the amino acid sequence of SEQ ID NO: 27. 
     
     
         54 . The method of  claim 48 , wherein the antibody comprises an acyl donor glutamine-containing tag engineered at a specific site. 
     
     
         55 . The method of  claim 54 , wherein the acyl donor glutamine-containing tag comprises an amino acid sequence selected from the group consisting of Q, LOG, LLQGG (SEQ ID NO:77), LLQG (SEQ ID NO:78), LSLSQG (SEQ ID NO: 79), GGGLLQGG (SEQ ID NO: 80), GLLQG (SEQ ID NO: 81), LLQ, GSPLAQSHGG (SEQ ID NO: 82), GLLQGGG (SEQ ID NO: 83), GLLQGG (SEQ ID NO: 84), GLLQ (SEQ ID NO: 85), LLQLLQGA (SEQ ID NO: 86), LLQGA (SEQ ID NO: 87), LLQYQGA (SEQ ID NO: 88), LLQGSG (SEQ ID NO: 89), LLQYQG (SEQ ID NO: 90), LLQLLQG (SEQ ID NO: 91), SLLQG (SEQ ID NO: 92), LLQLQ (SEQ ID NO: 93), LLQLLQ (SEQ ID NO: 94), LLQGR (SEQ ID NO: 95), LLQGPP (SEQ ID NO: 96), LLQGPA (SEQ ID NO: 97), GGLLQGPP (SEQ ID NO: 98), GGLLQGA (SEQ ID NO: 99), LLQGPGK (SEQ ID NO: 100), LLQGPG (SEQ ID NO: 101), LLQGP (SEQ ID NO: 102), LLQP (SEQ ID NO: 103), LLQPGK (SEQ ID NO: 104), LLQAPGK (SEQ ID NO: 105), LLQGAPG (SEQ ID NO: 106), LLQGAP (SEQ ID NO: 107), and LLQLQG (SEQ ID NO: 108). 
     
     
         56 . The antibody of  claim 55 , wherein the acyl donor glutamine-containing tag is LLQG (SEQ ID NO: 78). 
     
     
         57 . The method of  claim 48 , wherein the linker is a cleavable linker. 
     
     
         58 . The method of  claim 57 , wherein the cleavable linker is selected from the group consisting of Ac-Lys-Gly (acetyl-lysine-glycine), aminocaproic acid, Ac-Lys-p-Ala (acetyl-lysine-p-alanine), amino-PEG2 (polyethylene glycol)-C2, amino-PEG3-C2, amino-PEG6-C2, Ac-Lys-Val-Cit-PABC (acetyl-lysine-valine-citrulline-p-aminobenzyloxycarbonyl), amino-PEG6-C2-Val-Cit-PABC, aminocaproyl-Val-Cit-PABC, [(3R,5R)-1-{3-[2-(2-aminoethoxy)ethoxy]propanoyl}piperidine-3,5-diyl]bis-Val-Cit-PABC, [(3S,5S)-1-{3-[2-(2-aminoethoxy)ethoxy]propanoyl}piperidine-3,5-diyl]bis-Val-Cit-PABC, putrescine, and Ac-Lys-putrescine. 
     
     
         59 . The method of  claim 57 , wherein the cleavable linker is Ac-Lys-Val-Cit-PABC (acetyl-lysine-valine-citrulline-p-aminobenzyloxycarbonyl). 
     
     
         60 . The method of  claim 48 , wherein the cytotoxic agent is selected from the group consisting of an anthracycline, an auristatin, a camptothecin, a combretastatin, a CBI dimer, a cyclopropylpyrroloindoline (CPI) dimer, a CTI dimer, a dolastatin, a duocarmycin, an enediyne, a geldanamycin, an indolino-benzodiazepine dimer, a maytansine, a puromycin, a pyrrolobenzodiazepine dimer, a taxane, a vinca alkaloid, a tubulysin, a hemiasterlin, a spliceostatin, a pladienolide, and stereoisomers, isosteres, analogs, or derivatives thereof. 
     
     
         61 . The method of  claim 60 , wherein the cytotoxic agent is a cyclopropylpyrroloindoline (CPI) dimer. 
     
     
         62 . The method of  claim 61 , wherein the CPI dimer is C 31 H 31 Cl 2 N 4 O 7 P, or a pharmaceutically acceptable salt or solvate thereof, optionally wherein the CPI dimer salt is C 31 H 31 Cl 2 N 4 O 7 P·C 2 HF 3 O 2 . 
     
     
         63 . A method of treating or ameliorating cancer in a subject expressing CD123 comprising administering to the subject in need thereof an effective amount of an antibody-drug conjugate;
 wherein the antibody-drug conjugate comprises an antibody which specifically binds to CD123, a linker, and a cytotoxic agent;   wherein the antibody binds CD123 without inhibiting the IL-3 signaling pathway.   
     
     
         64 . The method of  claim 63 , wherein the cancer is selected from the group consisting of acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN), hairy cell leukemia, B-cell non-Hodgkin's lymphoma (NHL), multiple myeloma, malignant plasma cell neoplasm, Hodgkin's lymphoma, nodular lymphocyte predominant Hodgkin's lymphoma, Kahler's disease and Myelomatosis, plasma cell leukemia, plasmacytoma, B-cell prolymphocytic leukemia, chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), follicular lymphoma, Burkitt's lymphoma, marginal zone lymphoma, mantle cell lymphoma, large cell lymphoma, precursor B-lymphoblastic lymphoma, myeloid leukemia, Waldenstrom's macroglobulinemia, diffuse large B cell lymphoma, follicular lymphoma, marginal zone lymphoma, mucosa-associated lymphatic tissue lymphoma, small cell lymphocytic lymphoma, mantle cell lymphoma, Burkitt lymphoma, primary mediastinal (thymic) large B-cell lymphoma, lymphoplasmacytic lymphoma, Waldenstrom macroglobulinemia, nodal marginal zone B cell lymphoma, splenic marginal zone lymphoma, intravascular large B-cell lymphoma, primary effusion lymphoma, lymphomatoid granulomatosis, T cell/histiocyte-rich large B-cell lymphoma, primary central nervous system lymphoma, primary cutaneous diffuse large B-cell lymphoma (leg type), EBV positive diffuse large B-cell lymphoma of the elderly, diffuse large B-cell lymphoma associated with inflammation, intravascular large B-cell lymphoma, ALK-positive large B-cell lymphoma, plasmablastic lymphoma, large B-cell lymphoma arising in HHV8-associated multicentric Castleman disease, B-cell lymphoma unclassified with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma, B-cell lymphoma unclassified with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, and other B-cell related lymphoma. 
     
     
         65 . The method of  claim 64 , wherein the cancer is acute myeloid leukemia (AML). 
     
     
         66 . A method of treating a condition associated with cells expressing CD123 in a subject, the method comprising administering to the subject in need thereof an effective amount of an antibody-drug conjugate;
 wherein the antibody-drug conjugate comprises an antibody which specifically binds to CD123, a linker, and a cytotoxic agent;   wherein the linker is conjugated to the antibody at a specific site.   
     
     
         67 . The method of  claim 66 , wherein the antibody-to-drug ratio is about 2.