Cannon CP, et al. - This article was written with the objective to compare the utilization of two regimens of dual antithrombotic therapy that included dabigatran with the utilization of triple antithrombotic therapy that included warfarin among patients with atrial fibrillation who had undergone percutaneous coronary intervention (PCI). In this study, they found that, among patients with atrial fibrillation who had undergone PCI, dual therapy with dabigatran and a P2Y12 inhibitor resulted in a risk of bleeding events that were significantly lower than the risk with triple therapy with warfarin, a P2Y12 inhibitor, and aspirin; also, dual therapy with dabigatran was noninferior to triple therapy with warfarin with respect to the rate of thromboembolic events. In the dual-therapy regimens, each of the two doses of dabigatran led to a balance between the risk of bleeding and the prevention of thromboembolic events, which offers clinicians two additional options for the treatment of patients with varying risks of thromboembolic events and bleeding.

Methods

• For this study, they designed a multicenter trial. In this study, they randomly assigned 2725 patients with atrial fibrillation who had undergone PCI to triple therapy with warfarin plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and aspirin (for 1 to 3 months) (triple-therapy group) or dual therapy with dabigatran (110 mg or 150 mg twice daily) plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and no aspirin (110-mg and 150-mg dual-therapy groups).
• Elderly patients (≥80 years of age; ≥70 years of age in Japan) were randomly assigned to the 110-mg dual-therapy group or the triple-therapy group outside the United States.
• The primary endpoint was a major or clinically relevant nonmajor bleeding event amid follow-up (mean follow-up, 14 months).
• The trial also tested for the noninferiority of dual therapy with dabigatran (both doses combined) to triple therapy with warfarin with respect to the incidence of a composite effectiveness endpoint of thromboembolic events (myocardial infarction, stroke, or systemic embolism), death, or unplanned revascularization.

Results

• They observed that the incidence of the primary end point was 15.4% in the 110-mg dual-therapy group as compared with 26.9% in the triple-therapy group (hazard ratio, 0.52; 95% confidence interval [CI], 0.42 to 0.63; P<0.001 for noninferiority; P<0.001 for superiority) and 20.2% in the 150-mg dual-therapy group as compared with 25.7% in the corresponding triple-therapy group, which did not include elderly patients outside the United States (hazard ratio, 0.72; 95% CI, 0.58 to 0.88; P<0.001 for noninferiority).
• The incidence of the composite effectiveness end point was 13.7% in the two dual-therapy groups combined as compared with 13.4% in the triple-therapy group (hazard ratio, 1.04; 95% CI, 0.84 to 1.29; P=0.005 for noninferiority).
• The rate of serious adverse events did not vary significantly among the groups.