The present invention is directed to parenterally-administrable
microparticles for providing sustained-release of a therapeutic agent in
the body, where the microparticles include a polymeric core containing a
therapeutically effective amount of a therapeutic agent disposed therein,
a first film encapsulating the core, the first film prepared from a first
biodegradable polymer soluble in an appropriate solvent therefore, and a
second film encapsulating the core and the first film, the second film
prepared from a biodegradable polymer soluble in an appropriate solvent
therefore, wherein the first film is insoluble in the solvent used to
prepare the second film, and to parenterally-administrable compositions
containing such microparticles dispersed in a suitable carrier therefore.