Rivaroxaban, a direct factor Xa inhibitor, is a novel oral anticoagulant 
approved for stroke prevention in patients with nonvalvular atrial fibrillation 
and also approved in Europe (but not in the United States) to prevent recurrent 
ischemic events in patients with recent acute coronary syndromes. Advantages of 
rivaroxaban over oral anticoagulants such as warfarin are the lack of need for 
ongoing monitoring, a fixed-dose regimen, and fewer drug and food interactions. 
Drawbacks include a lack of an antidote and the absence of a widely available 
method to reliably monitor the anticoagulant effect. In patients at risk of 
stroke due to atrial fibrillation, rivaroxaban was noninferior compared to 
warfarin in preventing stroke/systemic embolism in the Rivaroxaban Once Daily 
Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for 
Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial 
and was associated with a similar risk of major bleeding; the incidence of 
intracranial hemorrhage was 33% lower with rivaroxaban. Concerns raised about 
the trial were the adequacy of warfarin management and the increase in event 
rate at the end of the trial. The drug acquisition cost of rivaroxaban is higher 
than that of warfarin although decision-analytic models suggest that it is cost 
effective in atrial fibrillation. In patients with recent acute coronary 
syndrome, low-dose rivaroxaban reduced mortality and the composite end point of 
death from cardiovascular causes, myocardial infarction and stroke, but this was 
accompanied by an increased risk of intracranial hemorrhage and major bleeding 
in the Rivaroxaban in Combination With Aspirin Alone or With Aspirin and a 
Thienopyridine in Patients With Acute Coronary Syndromes-Thrombolysis in 
Myocardial Infarction (ATLAS ACS 2-TIMI) 51 trial. Thus, rivaroxaban appears to 
be a valuable addition to the therapeutic armamentarium in atrial fibrillation 
although caution should be exercised, given the limited experience in 
combination with novel oral antiplatelet agents. The role of rivaroxaban as part 
of a modern regimen in acute coronary syndrome continues to be evaluated.