BACKGROUND AND PURPOSE: In Rivaroxaban Once Daily Oral Direct Factor Xa Inhibitor Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) trial, rivaroxaban was noninferior to dose-adjusted warfarin in preventing stroke or systemic embolism among patients with nonvalvular atrial fibrillation at moderate to high stroke risk. Because of differences in patient demographics, epidemiology, and stroke risk management in East Asia, outcomes and relative effects of rivaroxaban versus warfarin were assessed to determine consistency among East Asians versus other ROCKET AF participants. METHODS: Baseline demographics and interaction of treatment effects of rivaroxaban and warfarin among patients within East Asia and outside were assessed. RESULTS: A total of 932 (6.5%) ROCKET AF participants resided in East Asia. At baseline, East Asians had lower weight, creatinine clearance, and prior vitamin K antagonist use; higher prevalence of prior stroke; and less congestive heart failure and prior myocardial infarction than other participants. Despite higher absolute event rates for efficacy and safety outcomes in East Asians, the relative efficacy of rivaroxaban (20 mg once daily; 15 mg once daily for creatinine clearance of 30-49 mL/min) versus warfarin with respect to the primary efficacy end point (stroke/systemic embolism) was consistent among East Asians and non-East Asians (interaction P=0.666). Relative event rates for the major or nonmajor clinically relevant bleeding in patients treated with rivaroxaban and warfarin were consistent among East Asians and non-East Asians (interaction P=0.867). CONCLUSIONS: Observed relative efficacy and safety of rivaroxaban versus warfarin were similar among patients within and outside East Asia. Rivaroxaban, 20 mg once daily, is an alternative to warfarin for stroke prevention in East Asians with nonvalvular atrial fibrillation.