An implantable medical device comprising (a) a metallic substrate and (b) a bisphosphonate wherein both phosphorus atoms contained in the bisphosphonate are covalently attached to a same carbon atom. The bisphosphonate continuously coats the external surface of the metallic substrate as monolayer and as outermost layer. At least one phosphonate moiety of the bisphosphonate is covalently and directly bonded to the external surface of the metallic substrate and/or covalently bonded to another molecule of the bisphosphonate in the coating.