Sintering technique for the preparation of polymer matrices for the controlled release of macromolecules

A new method for making polymeric systems for the controlled release of macromolecular drugs is described. The method consists of mixing drug and polymer (ethylene-vinyl acetate copolymer) powders below the glass transition temperature of the polymer and compressing the mixture at a temperature above the glass transition point. The macromolecule is not exposed to organic solvent during the fabrication process. Kinetic studies indicate that there is sustained release, and the bioactivity of macromolecules tested is unchanged throughout the sintering and release processes.