The goal of this study was to demonstrate superiority of sirolimus-eluting stents (SES) over bare-metal stents (BMS) and of abciximab over no abciximab in primary percutaneous coronary intervention (PCI). Drug-eluting stents (DES) are increasingly used in primary PCI, but the recommendations for use in primary PCI are based on a few randomized controlled trials with selected patients. The usefulness of abciximab in primary PCI is not established. Nine hundred seven patients referred to the Catharina Hospital were randomized to SES or BMS, and to abciximab or no abciximab in a prospective, randomized, open 2 × 2 factorial trial with blinded evaluation. Primary endpoint was major adverse cardiac and cerebrovascular events (MACCE), defined as the composite of death, myocardial infarction (MI), stroke, repeat revascularization, and bleeding at 1 year (stent arm) and the composite of death, target vessel MI, target vessel revascularization (TVR), and bleeding at 30 days (abciximab arm). At 1 year, the rate of MACCE was lower in the SES arm (16.5% vs. 25.8%, p = 0.001), mainly driven by less repeat revascularization (9.8% vs. 16.8%; p = 0.003) and without influencing the cumulative incidence of death and MI (5.2% vs. 5.8%; p = 0.68). At 30 days, the rate of the composite of death, target vessel MI, TVR, and bleeding was lower in the abciximab arm (8.2% vs. 12.4%, p = 0.04), mainly driven by less TVR due to less stent thrombosis (1.2% vs.7.4%, p < 0.001). However, bleeding complications occurred more frequently in the abciximab group (5.7% vs. 2.8%, p = 0.03). Primary PCI with SES reduces adverse events at 1 year, mainly by reduction of repeat revascularization, whereas abciximab reduces early stent thrombosis, at the expense of more bleeding complications. (Comparison of Drug Eluting and Bare Metal Stents With or Without Abciximab in ST Elevation Myocardial Infarction [DEBATER]; NCT00986050).