Patent ID: 8217123

Claim:
A polymer conjugate comprising the structure: POLY A -L-S—S—Y-POLY B -Y—S—S-A wherein: each of POLY A and POLY B is a water soluble polymer segment, where POLY B has a molecular weight of 10 KDa or less, and the sum of the molecular weights of POLY A and POLY B is at least 3 KDa; each Y is independently a divalent linking group consisting of a saturated or unsaturated hydrocarbon backbone which is three to ten carbon atoms in length and has substituents which are independently selected from hydrogen, lower alkyl, lower alkenyl, and non-interfering substituents as defined herein, where two such alkyl and/or alkenyl substituents on different carbon atoms of the backbone may be linked so as to form a cycloalkyl, cycloalkenyl, or aryl group; L is a linker group; each S—S is a disulfide group attached to an sp 3 hybridized carbon of the adjacent Y; and A is a covalently linked residue of a pharmacologically active molecule.