Patent ID: 6814980
Filing Date: 2004-11-09
Classification: A61K

Abstract:
A method for making microspheres containing a condensed polyanionic bioactive agent, comprising the steps of:(a) dissolving at least one biocompatible biodegradable polymer in a water-immiscible organic solvent to yield an organic phase; (b) dissolving a polyanionic bioactive agent in water to yield a first aqueous phase; (c) emulsifying the organic and first aqueous phases to yield a first emulsion; (d) dissolving a condensing agent in water to yield a second aqueous phase wherein the condensing agent is a polycation, the polycation being at least one of polylysines, polypeptides, and polyamines; (e) emulsifying the first emulsion and the second aqueous phase to yield a second emulsion; and (f) removing the organic solvent from the second emulsion to yield microspheres containing the condensed polyanionic bioactive agent.