Second Generation" Drug-Eluting Stents Implantation Followed by Six Versus Twelve-Month - Dual Antiplatelet Therapy

Prospective, randomized, non-inferiority, multicenter, international study.In total 4000 patients (70 centers in Europe) with de novo lesions in native coronary arteries who meet the eligibility criteria randomized to 6 versus 12 month dual antiplatelet therapies following a second generation DES implantation. Assuming that the true proportion of thrombotic events is equal to 2.3% for both regimens (6-month and 12-month clopidogrel) 2000 patients for each treatment group are necessary to demonstrate a non-inferiority of the 6-months regimen if the proportion of thrombotic events will be no more than 3.5% with a power of 0.80 and a significance level of 0.05 (one-tail). If the non-inferiority hypothesis will be rejected, the superiority hypothesis (12-months regimen is superior to the 6-months-regimen) will be tested at a significance level of 0.05 (two-tails). The maximal not clinically relevant difference for the non-inferiority hypothesis of 1.2 % more thrombotic events has to be considered together with the lower expected number of bleeding events in the 6-months regimen. All the analysis will be done as "intention-to-treat" analysis.