| abstract |
(57) [Summary]nAn implant with a coating comprising a polymer matrix is swollen in a pharmaceutical solution, whereby the pharmaceutically active compound is absorbed into the polymer matrix. Implanting this product results in the release of the pharmaceutically active compound from the coating. The polymer is preferably formed from an zwitterionic monomer, most preferably an ethylenically unsaturated monomer comprising 2-methacryloyloxyethyl-2′-trimethylammonium ethyl phosphate inner salt. The monomer from which the polymer is formed may further comprise surface binding monomers such as hydrophobic containing monomers, and cross-linking monomers, the content of which may be used to control swellability. Preferably, the implant is a stent and the coating on the outer surface is thicker than the coating on the inner surface. Drug release may be controlled by the choice of comonomer. This implant is preferably a stent for use in the cardiovascular system. |