Multivalent carriers of bi-specific antibodies

Abstract

Provided herein are targetable constructs that are multivalent carriers of bi-specific antibodies, i.e., each molecule of a targetable construct can serve as a carrier of two or more bi-specific antibodies. Also provided are targetable complexes formed by the association of a targetable construct with two or more bi-specific antibodies. The targetable constructs and targetable complexes of the invention are incorporated into biosensors, kits and pharmaceutical compositions, and are used in a variety of therapeutic and other methods.

1 . A bi-specific antibody comprising the structure [IgG 1 ]-[scFv]2; 
 wherein said antibody comprises a pair of heavy chains and a pair of light chains,    wherein each heavy chain comprises an IgG1 heavy chain and an scFv, wherein said scFv is fused to the C-terminus of said IgG 1 heavy chain, optionally via a linker peptide.    
     
     
         2 . The antibody according to  claim 1 , wherein the binding sites formed by said heavy chain and said light chain specifically binds to an epitope on a targeted tissue.  
     
     
         3 . The antibody according to  claim 2 , wherein each of said scFv moieties specifically binds to a carrier epitope.  
     
     
         4 . The antibody according to  claim 1 , wherein said IgG1 is a human, humanized, chimeric, or CDR-grafted antibody.  
     
     
         5 . The antibody according to  claim 1 , wherein each of said scFv molecules is human, humanized, or CDR-grafted.  
     
     
         6 . The antibody according to  claim 5 , wherein said antibody further comprises a bioactive moiety.  
     
     
         7 . The antibody according to  claim 6 , wherein said bioactive moiety is selected from the group consisting of a drug, a prodrug, an enzyme, a hormone, an immunomodulator, an oligonucleotide; a radionuclide, an image enhancing agent and a toxin.  
     
     
         8 . The antibody according to  claim 1 , wherein said antibody is selected from the group consisting of [hMN14-IgG1]-[734scFv] 2  and [hMN14-IgG1 (1253A) ]-[734scFv] 2 .  
     
     
         9 . The antibody according to  claim 1 , wherein said antibody is selected from the group consisting of [hMN14-IgG1]-[679scFv] 2  and [hMN14-IgG1 (1253A) ]-[679scFv] 2 .  
     
     
         10 . The antibody according to  claim 1 , wherein said antibody is selected from the group consisting of [hA20-IgG1]-[734scFv] 2  and [hA20-IgG1 (1253A) ]-[734scFv] 2 .  
     
     
         11 . The antibody according to  claim 1 , wherein said antibody is selected from the group consisting of [hA20-IgG1]-[679scFv] 2  and [hA20-IgG1 (1253A) ]-[679scFv] 2 .  
     
     
         12 . The antibody according to  claim 1 , wherein said antibody is selected from the group consisting of [hLL2-IgG1]-[734scFv] 2  and [hLL2-IgG1 (1253A) ]-[734scFv] 2 .  
     
     
         13 . The antibody according to  claim 1 , wherein said antibody is selected from the group consisting of [hLL2-IgG1]-[679scFv] 2  and [hLL2-IgG1 (1253A) ]-[670scFv] 2 .  
     
     
         14 . A binding complex comprising a tetravalent binding molecule bound to a targetable construct, wherein said tetravalent binding molecule comprises two binding sites for a carrier epitope and two binding sites for a target epitope, and 
 wherein said targetable construct comprises a molecular scaffold and at least two carrier epitopes.    
     
     
         15 . The binding complex according to  claim 14 , wherein said targetable construct comprises at least two pairs of carrier epitopes and wherein at least two of said tetravalent binding molecules are bound to said targetable construct.  
     
     
         16 . The binding complex according to  claim 15 , wherein said at least two pairs of carrier epitopes comprise a first pair and a second pair, wherein said first and second pair are different epitopes, and wherein a first tetravalent binding molecule is bound to said first pair of carrier epitopes and a second tetravalent binding molecule is bound to said second pair of carrier epitopes.  
     
     
         17 . The binding complex according to  claim 16 , wherein said first and second pair of carrier epitopes are different epitopes.  
     
     
         18 . The binding complex according to  claim 17 , wherein said first and second tetravalent binding molecules bind to the same target epitope.  
     
     
         19 . The binding complex according to  claim 14 , wherein said targetable construct is selected from the group consisting of IMP 246, IMP 156, IMP 192 and IMP 222.  
     
     
         20 . The binding complex according to  claim 14 , wherein said carrier epitope is a hapten.  
     
     
         21 . The binding complex according to  claim 14 , wherein said carrier epitope is a chelator, wherein said chelator optionally is bound to a metal ion.  
     
     
         22 . The binding complex according to  claim 21 , wherein said chelator is selected from the group consisting of DTPA, DOTA, benzyl DTPA, NOTA, and TETA.  
     
     
         23 . The binding complex according to  claim 14 , wherein said tetravalent binding molecule is a bi-specific antibody comprising the structure [IgG 1 ]-[scFv]2; 
 wherein said antibody comprises a pair of heavy chains and a pair of light chains,    wherein each heavy chain comprises an IgG1 heavy chain and an scFv, wherein said scFv is fused to the C-terminus of said IgG1 heavy chain, optionally via a linker peptide.    
     
     
         24 . The binding complex according to  claim 14 , wherein said molecular scaffold is a peptide or peptide derivative.  
     
     
         25 . The binding complex according to  claim 14 , wherein said target epitope is an antigen associated with a disease.  
     
     
         26 . The binding complex according to  claim 25 , wherein said disease is selected from the group consisting of hyperproliferative disease, pathogenic disease, cancer, cardiovascular disease, neurodegenerative disease, metabolic disease, and autoimmune disease  
     
     
         27 . The binding complex according to  claim 26 , wherein said target epitope is a tumor associated antigen associated with a type of cancer selected from the group consisting of acute lymphoblastic leukemia, acute myelogenous leukemia, biliary cancer, breast cancer, cervical cancer, chronic lymphocytic leukemia, chronic myelogenous leukemia, colorectal cancer, endometrial cancer, esophageal, gastric, head and neck cancer, Hodgkin's lymphoma, lung cancer, medullary thyroid, non-Hodgkin's lymphoma, ovarian cancer, pancreatic cancer, glioma, melanoma, liver cancer, prostate cancer, and urinary bladder cancer.  
     
     
         28 . The binding complex according to  claim 27 , wherein said target epitope is a tumor associated antigen selected from the group consisting of A3, antigen specific for A33 antibody, BrE3, CD1, CD1a, CD3, CD5, CD15, CD19, CD20, CD21, CD22, CD23, CD25, CD30, CD45, CD74, CD79a, CD80, HLA-DR, NCA 95, NCA90, HCG and its subunits, CEA, CSAp, EGFR, EGP-1, EGP-2, Ep-CAM, Ba 733, HER2/neu, KC4, KS-1, KS1-4, Le-Y, MAGE, MUC1, MUC2, MUC3, MUC4, PAM-4, PSA, PSMA, RS5, S100, TAG-72, p53, tenascin, IL-6, insulin growth factor-1 (IGF-1), Tn antigen, Thomson-Friedenreich antigens, tumor necrosis antigens, VEGF, 17-1A, an angiogenesis marker, a cytokine, an immunomodulator, an oncogene marker, an oncogene product, and other tumor associated antigens.  
     
     
         29 . A method of treating a disease in a subject, comprising administering to a subject suffering from said disease 
 (i) a tetravalent binding molecule comprising two binding sites for a carrier epitope and two binding sites for a target epitope, wherein said target epitope is an epitope associated with said disease,    (ii) optionally, a clearing agent, and    (iii) a targetable construct comprising a molecular scaffold and at least two carrier epitopes.    
     
     
         30 . The method according to  claim 29 , wherein said disease is selected from the group consisting of hyperproliferative disease, pathogenic disease, cancer, cardiovascular disease, neurodegenerative disease, metabolic disease, and autoimmune disease.  
     
     
         31 . The method according to  claim 29 , wherein said targetable construct further comprises a bioactive moiety.  
     
     
         32 . A method of diagnosing/detecting a disease in a subject, comprising administering to a subject suspected of suffering from said disease (i) a tetravalent binding molecule comprising two binding sites for a carrier epitope and two binding sites for a target epitope, 
 (ii) optionally, a clearing agent, and    (iii) a targetable construct comprising a molecular scaffold and at least two carrier epitopes, wherein said construct comprises a detectable label.    
     
     
         33 . The method according to  claim 32 , wherein said target epitope is comprised within, displayed by or released from one or more cells, tissues, organs or systems of said subject.  
     
     
         34 . A kit, comprising 
 (i) a tetravalent binding molecule comprising two binding sites for a carrier epitope and two binding sites for a target epitope,    (ii) optionally, a clearing agent, and    (iii) a targetable construct comprising a molecular scaffold and at least two carrier epitopes.    
     
     
         35 . A pharmaceutical composition comprising a bispecific antibody according to  claim 1.