NOVEL SUSTAINED RELEASE POLYMER
A polymer and a method for its preparation are provided. The polymer comprises poly(lactide), poly(lactide/glycolide) or poly(lactic acid/glycolic acid) segments bonded by ester linkages to both ends of an alkanediol core unit. The polymer is for use in a controlled release formulation for a medicament, preferably leuprolide acetate. The controlled release formulation is administered to a patient as a subcutaneous depot of a flowable composition comprising the polymer, a biocompatible solvent, and the medicament. Controlled release formulations comprising the polymer release leuprolide for treatment of prostate cancer patients over periods of 3-6 months.
1 . A polymer for use in manufacture of a controlled release formulation for leuprolide, comprising a structure of Formula I:
wherein:
R a is an alkane diradical comprising about 4 to about 8 carbon atoms;
R b is hydrogen or methyl with the proviso that both R b groups are identical;
R c is hydrogen or methyl with the proviso that both R c groups are identical;
each L/G independently comprises a lactide/glycolide copolymer segment;
the polymer has substantially no titratable carboxylic acid groups, and
the polymer has a weight average molecular weight of from about 6 kD to about 200 kD.