The Food and Drug Administration reaffirmed its confidence in the data supporting the claim that rivaroxaban (Xarelto) is a safe and effective alternative to warfarin for preventing strokes and blood clots in patients with nonvalvular atrial fibrillation.
“The FDA concludes that Xarelto is a safe and effective alternative to warfarin in patients with atrial fibrillation,” the agency said in a statement released on Oct. 11.
Questions arose about the validity of the data collected in the pivotal trial that supported this indication for rivaroxaban, the ROCKET AF (Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation) study, because the Alere INRatio device used to monitor warfarin levels in the trial was subsequently found faulty and recalled by its manufacturer in July 2016.In response to these events the FDA “completed a variety of analyses to assess the impact that this faulty monitoring device had on the ROCKET AF study results. The agency has determined that effects on strokes or bleeding, including bleeding in the head, were minimal,” the agency said in its statement.
Researchers associated with ROCKET AF published their own analysis of the impact of the faulty device on bleeding rates among patients treated with warfarin in the trial and concluded that device malfunction did not appear to influence the results (N Engl J Med. 2016 Feb 25;374[8]:785-8).
Rivaroxaban is one of four new oral anticoagulants (NOACs) on the U.S. market that are alternatives to warfarin for stroke and clot prevention in patients with nonvalvular atrial fibrillation. An analysis of 2014 data on U.S. office-based prescriptions for NOACs in atrial fibrillation patients showed that rivaroxaban was by far the most commonly prescribed drug in the class, prescribed for patients during 48% of physician office visits that led to a NOAC prescription (Am J Med. 2015 Dec;128[12]:1300-5).
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