Bayer and Johson & Johnson have been boosted by the news that regulators in the USA have given the green light to their potential blockbuster Xarelto to prevent stroke in people with irregular heartbeat.

Specifically, the US Food and Drug Administration has approved Xarelto (rivaroxaban) to reduce the risk of stroke and systemic embolism in patients with non-valvular AF. The approval is based on data from the 14,264-patient Phase III ROCKET AF trial, which showed that Xarelto was equivalent to warfarin in terms of its safety and efficacy.

The approval comes a couple of months after the agency's Cardiovascular and Renal Drugs advisory committee voted 9-2 in favour of backing the oral factor Xa inhibitor in the AF indication, despite qualms from FDA staffers the statistical analyses used in ROCKET-AF. Xarelto was approved in July for the prevention of deep vein thrombosis which may lead to a pulmonary embolism in people undergoing knee or hip replacement surgery.

The FDA has added a black box warning to make clear that people using Xarelto should not discontinue treatment before talking with their doctor, as that can increase the risk of stroke.

Still, the approval is clearly good news for Bayer and J&J, as Xarelto is the only oral anticoagulant approved in the USA that offers once-daily dosing, without the need for routine blood monitoring. Now the drug will go up against Boehringer Ingelheim's already-approved Pradaxa (dabigatran), while coming up on the rails is Bristol-Myers Squibb/Pfizer's Eliquis (apixaban).