Patent ID: 8323669

Claim:
A paclitaxel or docetaxel polymer conjugate in which a carboxylic acid group of a block copolymer having a polyethylene glycol moiety and two or more amidated polyaspartic acid moieties is ester-bonded to an alcoholic hydroxyl group of a paclitaxel or docetaxel represented by formula (I) wherein R1 represents a hydrogen atom or a (C1-C6) alkyl group; R2 represents a linking group; R3 represents a hydrogen atom or a (C1-C6) acyl group; R4 represents a residue of an alcoholic hydroxyl group of a paclitaxel or docetaxel; R5 represents a group selected from the group consisting of a (C1-C30) alkoxy group, a (C1-C30) aralkyloxy group, a (C1-C30) alkylamino group, a di(C1-C30) alkylamino group, an amino acid with a protected carboxyl group and —N(R6)CONH(R7) wherein R6 and R7, which may be identical or different, each represent a (C3-C6) cycloalkyl group, or a (C1-C5) alkyl group which may be substituted with a tertiary amino group; t represents an integer from 5 to 11,500; d, e, f, g, h, i and j each independently represent an integer from 0 to 200; provided that d+e is an integer from 1 to 200, and d+e+f+g+h+i+j is an integer from 3 to 200; and the respective constituent units of the polyaspartic acid are bound in any order.