Multispecific antigen-binding molecules and uses thereof

Abstract

The present invention provides multispecific antigen-binding molecules and uses thereof. The multispecific antigen-binding molecules comprise a first antigen-binding domain that specifically binds a target molecule, and a second antigen-binding domain that specifically binds an internalizing effector protein. The multispecific antigen-binding molecules of the present invention can, in some embodiments, be bispecific antibodies that are capable of binding both a target molecule and an internalizing effector protein. In certain embodiments of the invention, the simultaneous binding of the target molecule and the internalizing effector protein by the multispecific antigen-binding molecule of the present invention results in the attenuation of the activity of the target molecule to a greater extent than the binding of the target molecule alone. In other embodiments of the invention, the target molecule is a tumor associated antigen, and the simultaneous binding of the tumor associated antigen and the internalizing effector protein by the multispecific antigen-binding molecule of the present invention causes or facilitates the targeted killing of tumor cells.

What is claimed is: 
     
         1 . A multispecific antigen-binding molecule comprising:
 a first antigen-binding domain (D1); and   a second antigen-binding domain (D2);   wherein D1 specifically binds a target molecule (T); and   wherein D2 specifically binds an internalizing effector protein (E);   wherein the simultaneous binding of T and E by the multispecific antigen-binding molecule attenuates the activity of T to a greater extent than the binding of T by D1 alone.   
     
     
         2 . The multispecific antigen-binding molecule of  claim 1 , wherein E is a cell surface-expressed molecule that is directly internalized into the cell. 
     
     
         3 . The multispecific antigen-binding molecule of  claim 2 , wherein E is selected from the group consisting of CD63, MHC-I, Kremen-1, Kremen-2, LRP5, LRP6, transferrin receptor, LDLr, MAL, V-ATPase, and ASGR. 
     
     
         4 . The multispecific antigen-binding molecule of  claim 2 , wherein D2 comprises a ligand, or portion of a ligand, that specifically binds E. 
     
     
         5 . The multispecific antigen-binding molecule of  claim 1 , wherein E is a soluble ligand that is internalized into a cell via the interaction between E and an internalizing cell surface-expressed receptor molecule. 
     
     
         6 . The multispecific antigen-binding molecule of  claim 5 , wherein E is transferrin or a portion thereof that is capable of binding to membrane-expressed transferrin receptor. 
     
     
         7 . The multispecific antigen-binding molecule of  claim 5 , wherein D2 comprises a receptor, or ligand-binding portion of a receptor, that specifically binds E. 
     
     
         8 . The multispecific antigen-binding molecule of  claim 1 , wherein T is a cell surface-expressed target molecule. 
     
     
         9 . The multispecific antigen-binding molecule of  claim 8 , wherein T is selected from the group consisting of IL-4R, IL-6R, PRLR, Nav1.7, GCGR, and HLA-B27. 
     
     
         10 . The multispecific antigen-binding molecule of  claim 8 , wherein D1 comprises a ligand, or portion of a ligand, that specifically binds T. 
     
     
         11 . The multispecific antigen-binding molecule of  claim 1 , wherein T is an intracellular precursor of a secreted or transmembrane protein. 
     
     
         12 . The multispecific antigen-binding molecule of  claim 1 , wherein T is a soluble target molecule. 
     
     
         13 . The multispecific antigen-binding molecule of  claim 12 , wherein T is selected from the group consisting of IL-4, IL-6, IL-13, SOST, and DKK1. 
     
     
         14 . The multispecific antigen-binding molecule of  claim 12 , wherein D1 comprises a receptor, or ligand-binding portion of a receptor, that specifically binds T. 
     
     
         15 . The multispecific antigen-binding molecule of  claim 1 , wherein D1 and/or D2 exhibits pH-dependent binding to its antigen. 
     
     
         16 . The multispecific antigen-binding molecule of  claim 15 , wherein D1 binds T with lower affinity at acidic pH as compared to neutral pH; and/or wherein D2 binds E with lower affinity at acidic pH as compared to neutral pH. 
     
     
         17 . The multispecific antigen-binding molecule of  claim 1 , wherein D1 and/or D2 comprise(s) at least one antibody variable region. 
     
     
         18 . The multispecific antigen-binding molecule of  claim 17 , wherein D1 and/or D2 comprise(s) a heavy chain variable region (HCVR) and a light chain variable region (LCVR). 
     
     
         19 . The multispecific antigen-binding molecule of  claim 18 , wherein the multispecific antigen-binding molecule is a bispecific antibody. 
     
     
         20 . The multispecific antigen-binding molecule of  claim 1 , wherein D1 is derived from an antigen-binding molecule that binds but does not substantially inactivate T on its own. 
     
     
         21 . A method for inactivating or attenuating the activity of a target molecule (T), the method comprising contacting T and an internalizing effector protein (E) with a multispecific antigen-binding molecule, wherein the multispecific antigen-binding molecule comprises a first antigen-binding domain (D1) and a second antigen-binding domain (D2), wherein D1 specifically binds T, and wherein D2 specifically binds E; and wherein the simultaneous binding of T and E by the multispecific antigen-binding molecule causes inactivation of T to a greater extent than the binding of T by D1 alone. 
     
     
         22 . The method of  claim 21 , wherein E is a cell surface-expressed molecule that is directly internalized into the cell. 
     
     
         23 . The method of  claim 21 , wherein E is a soluble ligand that is internalized into a cell via the interaction between E and an internalizing cell surface-expressed receptor molecule. 
     
     
         24 . The method of  claim 21 , wherein T is a cell surface-expressed target molecule. 
     
     
         25 . The method of  claim 21 , wherein T is a soluble target molecule. 
     
     
         26 . The multispecific antigen-binding molecule of  claim 1 , wherein D2 comprises an antigen-binding portion of an anti-CD63 antibody. 
     
     
         27 . The multispecific antigen-binding molecule of  claim 26 , wherein D1 comprises an antigen-binding portion of an anti-IL-4R antibody. 
     
     
         28 . The multispecific antigen-binding molecule of  claim 26 , wherein D1 comprises an antigen-binding portion of an anti-SOST antibody. 
     
     
         29 . A multispecific antigen-binding molecule comprising:
 a first antigen-binding domain (D1); and   a second antigen-binding domain (D2);   wherein D1 specifically binds a target molecule (T); and   wherein D2 binds an internalizing effector protein (E);   wherein T is a tumor-associated antigen;   and wherein the simultaneous binding of T and E by the multispecific antigen-binding molecule causes internalization of the multispecific antigen-binding molecule into a tumor cell.   
     
     
         30 . The multispecific antigen-binding molecule of  claim 29 , wherein the multispecific antigen-binding molecule is conjugated to a drug, toxin or radioisotope. 
     
     
         31 . The multispecific antigen-binding molecule of  claim 29 , wherein D2 binds E with low affinity. 
     
     
         32 . A method of targeting a tumor in a subject, the method comprising administering to the subject the multispecific antigen-binding molecule of  claim 29 , and a second antigen-binding protein that specifically binds T at an epitope that is non-overlapping with the epitope to which D1 binds. 
     
     
         33 . The method of  claim 32 , wherein the second antigen-binding protein is conjugated to a drug, toxin or radioisotope.