The Food and Drug Administration on Nov. 4 approved rivaroxaban to reduce the risk of stroke in nonvalvular atrial fibrillation.
It is the second approval for the anticoagulant. In July, rivaroxaban (Xarelto) was approved for reducing the risk of blood clots, deep vein thrombosis, and pulmonary embolism after knee or hip replacement surgery. The new indication may spur more use of the product, as physicians continue to look for alternatives to warfarin.
"This approval gives doctors and patients another treatment option for a condition that must be managed carefully," said Dr. Norman Stockbridge, director of the Division of Cardiovascular and Renal Products in the FDA’s Center for Drug Evaluation and Research, in a statement.
Rivaroxaban, sold by Janssen Pharmaceuticals Inc., is the only oral anticoagulant approved in the United States thus far that offers once-daily dosing, without the need for routine blood monitoring. It is, however, the second warfarin alternative. In October 2010, the agency approved dabigatran (Pradaxa) for stroke prevention in AF.
While dabigatran has been embraced by physicians – with some 250,000 prescriptions issued by late August – rivaroxaban may face a less enthusiastic audience. At an FDA advisory panel meeting in September on the drug, the panel urged that it only be used as a third-line therapy. Panelists generally said that rivaroxaban did not appear to be as effective as dabigatran, or even warfarin, in some cases.
The approval of rivaroxaban was based on the 14,000-patient study, ROCKET AF (Rivaroxaban Once-daily oral direct Factor Xa inhibition Compared with vitamin K antagonism for the prevention of stroke and Embolism Trial in Atrial Fibrillation). Rivaroxaban was found to be similar to warfarin in its ability to prevent stroke, said the FDA.
Dr. Robert M. Califf
"In clinical studies, Xarelto was shown to be effective in patients who are at increased risk of stroke, and especially in those with co-morbidities such as high blood pressure or diabetes, and other factors that increase the risk of stroke," said Dr. Robert M. Califf, ROCKET AF study co-chairman and vice chancellor for clinical research at Duke University, Durham, N.C., in a statement issued by Janssen.
"These patients represent many of those with the most to gain from effective anticoagulation."
According to the FDA, bleeding was the most common adverse event reported by patients treated with rivaroxaban in ROCKET AF. The risk of major bleeding was similar to that of warfarin, but it caused less bleeding into the brain and more bleeding into the stomach and intestines.
The drug has a boxed warning that sudden discontinuation increases the risk of stroke.