Abstract
OBJECTIVES: The aim of this study was to determine if rivaroxaban is associated with a reduction in stent thrombosis among patients with acute coronary syndromes (ACS) in the ATLAS-ACS 2 TIMI 51 (Anti-Xa Therapy to Lower Cardiovascular Events in Addition to Standard Therapy in Subjects With Acute Coronary Syndrome-Thrombolysis in Myocardial Infarction 51) trial. BACKGROUND: Dual antiplatelet therapy (DAPT) has been the mainstay of efforts to prevent stent thrombosis. Because thrombin is a potent stimulant of platelet activation, we hypothesized that inhibition of thrombin generation via factor Xa inhibition may further reduce the risk of stent thrombosis. METHODS: The ATLAS-ACS 2 TIMI 51 study was a placebo-controlled trial that randomly assigned 15,526 patients with recent ACS to receive twice-daily doses of either 2.5 mg or 5 mg of rivaroxaban or placebo for a mean of 13 months and up to 31 months. RESULTS: Among patients who had a stent placed before or at the time of the index event, rivaroxaban significantly reduced independently adjudicated Academic Research Consortium definite and probable stent thrombosis in the pooled (1.9% vs. 1.5%; hazard ratio [HR]: 0.65; p = 0.017) and the 2.5 mg twice-daily (1.9% vs. 1.5%; HR: 0.61; p = 0.023) treatment groups when compared with placebo, with a trend toward a reduction in the 5 mg twice-daily treatment group (1.9% vs. 1.5%; HR: 0.70; p = 0.089). Among patients who received both aspirin and a thienopyridine (stratum 2), the benefit of rivaroxaban emerged during the period of active treatment with DAPT (HR: 0.68; 95% CI: 0.50 to 0.92, combined rivaroxaban group vs. placebo). Among stented patients who were treated with dual antiplatelet therapy, there was a mortality reduction among those treated with twice-daily rivaroxaban 2.5 mg (HR: 0.56; 95% CI: 0.35 to 0.89; p = 0.014). CONCLUSIONS: Among stented patients with ACS treated with DAPT, the administration of twice-daily rivaroxaban 2.5 mg was associated with a reduction in stent thrombosis and mortality. (An Efficacy and Safety Study for Rivaroxaban in Patients With Acute Coronary Syndrome; NCT00809965).
