US Patent 7101566 Polymer coated microparticles for sustained release

The present invention is directed to sustained release microparticle formulation for parenteral administration of biologically active substances, especially drugs. More specifically it relates to coated drug containing microparticles, wherein the coating is a synthetic, bioabsorbable, biocompatible polymeric wax that is the reaction product of a polybasic acid or derivative thereof, a polyol and a fatty acid, the polymeric wax having a melting point less than about 70° C., as determined by differential scanning calorimetry.