Dual antiplatelet therapy (DAPT) following coronary stenting is essential for the prevention of stent thrombosis, which can occur due to a response to the vascular scaffold, as well as to the local inflammation that occurs after angioplasty. DAPT after drug-eluting stent (DES) implantation is currently recommended for at least 12 months in the United States and for 6 months in Europe. Concern over very late stent thrombosis (occurring later than 1 year) with DES prompted a collaborative effort between the FDA and device and pharmaceutical manufacturers to study the efficacy of DAPT beyond 1 year in these patients.