Fibronectin-based binding molecules and uses thereof

Abstract

The invention provides fibronectin type III (Fn3)-based binding molecules that bind to a specific target antigen. The invention further provides bispecific Fn3-based binding molecules that bind to two or more targets simultaneously. The Fn3-based binding molecules of the invention can also be linked together to form multispecific Fn3-based binding molecules, and/or can be conjugated to a non-Fn3 moiety, such as, Human Serum Albumin (HSA), for improved half life and stability. The invention also provides methods for generating, screening and using Fn3-based binding molecules in a variety of therapeutic and diagnostic applications.

1 - 43 . (canceled) 
     
     
         44 . A Fn3-based binding molecule conjugate comprising an Fn3 domain that binds a target and a non-Fn3 moiety which extends half-life of the Fn3-based binding molecule. 
     
     
         45 . The Fn3-based binding molecule conjugate of  claim 44 , wherein the non-Fn3 moiety is selected from the group consisting of human serum albumin (HSA), an antibody Fc region and polyethylene glycol (PEG). 
     
     
         46 . The Fn3-based binding molecule conjugate of  claim 44 , wherein the non-Fn3 moiety is an antibody Fc region. 
     
     
         47 . The Fn3-based binding molecule conjugate of  claim 46 , wherein the antibody Fc region is an Fc region of IgG1. 
     
     
         48 . The Fn3-based binding molecule conjugate of  claim 44 , wherein the Fn3 domain is derived from the wild type tenth Fn3 domain of human fibronectin of SEQ ID NO:1. 
     
     
         49 . The Fn3-based binding molecule conjugate of  claim 48 , wherein the top BC, DE and FG loops of the Fn3 domain differ from the wild type Fn3 domain of SEQ ID NO:1. 
     
     
         50 . The Fn3-based binding molecule conjugate of  claim 49 , wherein the top loops differ from the wild type Fn3 domain of SEQ ID NO:1 at one or more of positions 23, 24, 25, 26, 27, 28, 29, 30, 51, 52, 53, 54, 55, 56, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87 and 88. 
     
     
         51 . The Fn3-based binding molecule conjugate of  claim 49 , wherein the top loops differ from the wild type Fn3 domain of SEQ ID NO:1 at positions 23, 24, 26, 27, 28, 29, 30, 54, 55, 56, 78, 79, 80, 81, 82, 83, 84, 85, 87 and 87. 
     
     
         52 . The Fn3-based binding molecule conjugate of  claim 51 , wherein the non-Fn3 moiety is an antibody Fc region. 
     
     
         53 . The Fn3-based binding molecule conjugate of  claim 52 , wherein the antibody Fc region is an Fc region of IgG1. 
     
     
         54 . A pharmaceutical composition comprising an Fn3-based binding molecule conjugate of  claim 44  and a pharmaceutically acceptable carrier. 
     
     
         55 . A pharmaceutical composition comprising an Fn3-based binding molecule conjugate of  claim 53  and a pharmaceutically acceptable carrier.