A method of inhibiting vascular intimal hyperplasia including: placing a stent within a blood vessel, the stent having a stent body of a cylindrical configuration having outer and inner surfaces with a diamond-like thin film coated on the surfaces, a first coated layer coating at least the outer surface of the stent body, the first coated layer being prepared of a first composition comprising a biodegradable polymer and a vascular intimal hyperplasia inhibitor of a kind, comprising argatroban, which does not inhibit proliferation of endothelial cells, the weight composition ratio of the polymer to the vascular intimal hyperplasia inhibitor being within the range of 8:2 to 7:3, and a second coated layer; and causing argatroban to be released from the stent to thereby inhibit the vascular intimal hyperplasia without inhibiting proliferation of endothelial cells.