Patent ID: 6511663
Filing Date: 2003-01-28
Classification: A61K,C07D,C07K

Abstract:
A tri- or tetra-valent monospecific antigen-binding protein comprising three or four Fab fragments bound to each other by a connecting structure that is a cross-linker compound of the general formula (1):R1CH(R2)NHCOR3 wherein R1 is a carboxyl (â€”CO2H) or esterified carboxyl (â€”CO2R) group or a group â€”COA where A is an effector or reporter molecule attached to the â€”CO group either directly or via a spacer group to form a carbon-carbon, or carbon-hetero atom linkage; R2 and R3, which may be the same or different, are each an optionally substituted straight or branched alkylene, alkenylene or alkynylene chain, wherein said chain is optionally interrupted by one or more â€”Oâ€” or â€”Sâ€” atoms, or â€”N(R4), where R4 is a hydrogen atom or a C1-6 alkyl group, â€”N(R4)COâ€”, â€”CON(R4)â€”, C5-8 cycloalkylene, C6-12 arylene or C5-10 heteroarylene groups, and wherein said chain contains one or more reactive functional groups such that the total number of reactive functional groups in R2 and R3 together is three or more; and wherein said protein is not a natural immunoglobulin.