Patent ID: 9187593
Filing Date: 2015-11-17
Classification: A61K,A61P,C08G

Abstract:
1. A biocompatible, biodegradable, non-hydrolyzed PLG low-burst copolymer material for a controlled release formulation having a weight average molecular weight of about 10 kilodaltons to about 23 kilodaltons and a ploydisperity index of about 1.4-2.0 which does not inclue a linear copolymer fraction characterized by a weight average molecular weight of about 4 kDa to about 10 kDa and a polydispersity index of about 1.4 to 2.5, and which PLG low burst copolymer material is produced by removing from a linear starting PLG copolymer material the linear copolymer fraction by a process of dissolving the starting PLG copolymer material in an organic solvent to provide a solution precipitating the low-burst copolymer material from the solution by contacting the solution with a non-solvent that is an organic liquid, and collecting the PLG low-burst copolymer material, the starting PLG copolymer material being produced by ring opening polymerization of cyclic dimer esters of lactide and glycolide or by condensation of lactic acid and glycolic acid and the stating PLG copolymer material being produced without hyrolysis of a higher molecular weight PLG copolymer material.