A coated implantable medical device 10 includes a structure 12 adapted for introduction into the vascular system, esophagus, trachea, colon, biliary tract, or urinary tract; at least one layer 18 of a bioactive material posited on one surface of structure 12; and at least one porous layer 20 posited over the bioactive material layer 18 posited on one surface of structure (12) and the bioactive-material-free surface. Preferably, the structure 12 is a coronary stent. The porous layer 20 is comprised of a polymer applied preferably by vapor or plasma deposition and provides a controlled release of the bioactive material. It is particularly preferred that the polymer is a polyamide, parylene or a parylene derivative, which is deposited without solvents, heat or catalysts, merely by condensation of a monomer vapor. Also disclosed is the method of manufacture of the device 10, as well as a method of using it in medical treatments.