Production and Use of Novel Peptide-Based Agents for Use with Bi-Specific Antibodies

Abstract

The present invention relates to a bi-specific antibody or antibody fragment having at least one arm that is reactive against a targeted tissue and at least one other arm that is reactive against a targetable conjugate. The targetable conjugate encompasses a hapten to which antibodies have been prepared. In preferred embodiments, the hapten is histamine-succinyl-glycine (HSG). In more preferred embodiments, the at least one arm comprises the CDR sequences of the HSG-binding 679 antibody. The targetable conjugate is attached to one or more therapeutic and/or diagnostic agents. The invention provides constructs and methods for producing the bispecific antibodies or antibody fragments, as well as methods for using them and kits comprising them.

1 . A method of treating or identifying diseased tissues in a subject, comprising:
 (A) administering to said subject a bispecific antibody or antibody fragment having at least one arm that binds a targeted tissue and at least one other arm that binds to a targetable conjugate, wherein said arm that binds a targetable conjugate is a 679 antibody or fragment thereof having the light chain complementarity determining region (CDR) sequences CDR1 (KSSQSLFNSRTRKNYLG, residues 24-40 of SEQ ID NO:2), CDR2 (WASTRES, residues 56-62 of SEQ ID NO:2) and CDR3 (TQVYYLCT, residues 95-102 of SEQ ID NO:2) and the heavy chain CDR sequences CDR1 (IYTMS, residues 30-34 of SEQ ID NO:4), CDR2 (TLSGDGDDIYYPDSVKG, residues 49-65 of SEQ ID NO:4) and CDR3 (VRLGDWDFDV, residues 98-107 of SEQ ID NO:4);   (B) optionally, administering to said subject a clearing composition, and allowing said composition to clear non-localized antibodies or antibody fragments from circulation;   (C) administering to said subject a targetable conjugate which comprises a carrier portion which comprises at least one HSG hapten and comprises at least one diagnostic and/or therapeutic agent.   
     
     
         2 . The method of  claim 1 , wherein said diagnostic agent emits 25-600 keV gamma particles and/or positrons. 
     
     
         3 . The method of  claim 1 , wherein said therapeutic agent is selected from the group consisting of a drug, a prodrug, a toxin, a radionuclide and an enzyme. 
     
     
         4 . The method of  claim 3 , wherein said prodrug is selected from the group consisting of epirubicin glucuronide, CPT-11, etoposide glucuronide, daunomicin glucuronide and doxorubicin glucuronide. 
     
     
         5 . The method of  claim 3 , wherein said toxin is selected from the group consisting of ricin, abrin, ribonuclease, DNase I, Staphylococcal enterotoxin-A, pokeweed antiviral protein, gelonin, diphtheria toxin,  Pseudomonas  exotoxin, and  Pseudomonas  endotoxin. 
     
     
         6 . The method of  claim 3 , wherein said therapeutic agent is an enzyme and said method further comprises:
 (D) administering to said subject
 i) a prodrug, wherein said enzyme is capable of converting said prodrug to a drug at the target site; or 
 ii) a drug which is capable of being detoxified in said subject to form an intermediate of lower toxicity, wherein said enzyme is capable of reconverting said detoxified intermediate to a toxic form, or 
 iii) a prodrug which is activated in said subject through natural processes and is subject to detoxification by conversion to an intermediate of lower toxicity, wherein said enzyme is capable of reconverting said detoxified intermediate to a toxic form. 
   
     
     
         7 . The method of  claim 3 , wherein said radionuclide is selected from the group consisting of  32 P,  33 P,  47 Sc,  64 Cu,  67 Cu,  67 Ga,  90 Y,  111 Ag,  111 In,  125 I,  131 I,  142 Pr,  153 Sm,  161 Tb,  166 Dy,  166 Ho,  177 Lu,  186 Re,  188 Re,  189 Re,  212 Pb,  212 Bi,  213 Bi,  211 At,  223 Ra and  225 Ac. 
     
     
         8 . The method of  claim 2 , wherein said diagnostic agent is selected from the group consisting of  18 F,  52 Fe,  62 Cu,  64 Cu,  67 Cu,  67 Ga,  68 Ga,  86 Y,  89 Zr,  94m Tc,  94 Tc,  99m Tc,  111 In,  123 I,  124 I,  125 I and  131 I. 
     
     
         9 . The method of  claim 1 , wherein said targetable conjugate comprises  10 B atoms, and said method further comprises the step of irradiating said boron atoms localized at said diseased tissue, thereby effecting BNCT of said diseased tissue. 
     
     
         10 . The method of  claims 8 , wherein said diagnostic agent is used to perform positron-emission tomography (PET). 
     
     
         11 . The method of  claim 1 , wherein said targetable conjugate comprises one or more image enhancing agents for use in magnetic resonance imaging (MRI). 
     
     
         12 . The method of  claim 11 , wherein said enhancing agent is selected from the group consisting of Mn, Fe and Gd. 
     
     
         13 . The method of  claim 1 , wherein the targetable conjugate comprises one or more agents for photodynamic therapy. 
     
     
         14 . The method of  claim 13 , wherein said agent for photodynamic therapy is a photosensitizer. 
     
     
         15 . The method of  claim 14 , wherein said photosensitizer is selected from the group consisting of benzoporphyrin monoacid ring A (BPD-MA), tin etiopurpurin (SnET2), sulfonated aluminum phthalocyanine (AlSPc) and lutetium texaphyrin (Lutex). 
     
     
         16 . The method of  claim 1 , wherein said at least one arm that binds a targeted tissue is a monoclonal antibody or a fragment of a monoclonal antibody. 
     
     
         17 . The method of  claim 1 , wherein said at least one arm that binds a targeted tissue is a human, chimeric or humanized antibody or a fragment of a human, chimeric or humanize antibody. 
     
     
         18 . The method of  claim 1 , wherein said at least one other arm that binds a targetable conjugate is a human, chimeric or humanized antibody or a fragment of a human, chimeric or humanized antibody. 
     
     
         19 . The method of  claim 1 , wherein said targetable conjugate comprises doxorubicin, SN-38, etoposide, methotrexate, 6-mercaptopurine or etoposide phosphate. 
     
     
         20 . The method of  claim 1 , wherein said targeted tissue is a tumor. 
     
     
         21 . The method of  claim 20 , wherein said tumor produces colon-specific antigen-p (CSAp) 
     
     
         22 . The method of  claim 21 , wherein the bispecific antibody comprises the Fv of MAb Mu9 and the Fv of MAb 679. 
     
     
         23 . The method of  claim 1 , wherein the bispecific antibody is a fusion protein. 
     
     
         24 . The method of  claim 20 , wherein the tumor produces carcinoembryonic antigen (CEA). 
     
     
         25 . The method of  claim 24 , wherein the bispecific antibody comprises the Fv of MAb MN14 and the Fv of MAb 679. 
     
     
         26 . The method of  claim 25 , wherein the fusion protein is trivalent, and incorporates the Fv of an antibody reactive with CSAp. 
     
     
         27 . The method of  claim 24 , wherein the bispecific antibody incorporates a Class III anti-CEA antibody and the Fv of 679. 
     
     
         28 . A method of intraoperatively identifying diseased tissues, in a subject, comprising:
 (a) administering a bispecific antibody or antibody fragment comprising at least one arm that binds a targeted tissue and at least one other arm that binds a targetable conjugate; and   administering a targetable conjugate selected from the group consisting of   
       
         
           
           
               
               
           
         
       
     
     
         29 . A method for the endoscopic or intravascular identification of diseased tissues, in a subject, comprising:
 (a) administering a bispecific antibody or antibody fragment comprising at least one arm that binds a targeted tissue and at least one other arm that binds a targetable conjugate; and   (b) administering a targetable conjugate comprising at least one diagnostic agent, wherein said targetable conjugate is selected from the group consisting of   
       
         
           
           
               
               
           
         
       
     
     
         30 . The method of  claim 29 , wherein said diagnostic agent is selected from the group consisting of  18 F,  52 Fe,  62 Cu,  64 Cu,  67 Cu,  67 Ga,  68 Ga,  86 Y,  89 Zr,  94m Tc,  94 Tc,  99m Tc,  111 In,  123 I,  124 I,  125 I,  131 I,  154-158 Gd and  175 Lu.