Patent ID: 8491906

Claim:
A specific binding member that binds human extra-domain B of fibronectin (ED-B) and comprising an antigen-binding site that comprises an antibody heavy chain variable region (VH domain) of an L19 antibody comprising the VH CDR1 sequence set forth in SEQ ID NO: 1, the VH CDR2 sequence set forth in SEQ ID NO: 2 and the VH CDR3 sequence set forth in SEQ ID NO: 3, an antibody light chain variable region (VL domain) of an L19 antibody comprising the VL CDR1 sequence set forth in SEQ ID NO: 4, the VL CDR2 sequence set forth in SEQ ID NO: 5 and the VL CDR3 sequence set forth in SEQ ID NO: 6; and a εS2-CH4 domain, wherein, said specific binding member exhibits greater accumulation in a tumor expressing said ED-B after 48 hours of administration compared to that achieved by a specific binding member comprising said VH and VL domains but lacking said εS2-CH4 domain.