Bioactive coatings for coronary stents: Modulation of cell proliferation by controlled release of anti-proliferative drugs

Drug eluting coronary stents coated with a bioactive and biostable polymer system (THBA70), based on acrylate copolymers bearing a salicylic acid derivative as side substituent, were evaluated. The microstructural architecture of the copolymer THBA70 comprises a random copolymer of a methacrylate derivative from triflusal (4-trifluoromethyl salicylic acid) with 45 mol% of THEMA (2-methacryloyloxyethyl [2-(acetyloxy)-4-(trifluoromethyl)] benzoate), which makes the system anti-thrombogenic with good adhesion to the surface of metallic stents. The bioactive coating prevented thrombosis, an adverse effect associated with the implantation of drug-eluting stents. The in vitro drug delivery of drug-eluting stents under dynamic conditions indicated excellent controlled drug release. The THBA70 films loaded with relatively low concentrations of taxol or simvastatin in contact with fibroblasts produced inhibition of cell proliferation with a dose-dependent bioactivity.