Advisors to the US Food and Drug Administration have voted comprehensively against expanding approval for Bayer/Johnson & Johnson's oral anticoagulant Xarelto for acute coronary syndrome.

The agency's Cardiovascular and Renal Drugs Advisory Committee voted 10-0, with one abstention, against the approval of Xarelto (rivaroxaban) in combination with standard antiplatelet therapy to reduce the risk of thrombotic cardiovascular events (heart attack, stroke or cardiovascular death) in patients with ACS. The vote was no great surprise given that earlier in the week, FDA staffers had issued a report saying the data provided by J&J to get approval for Xarelto to be used 90 days after patients experience serious chest pain or cardiac problems failed to show sufficient proof that the factor Xa inhibitor offered significant benefit.

The FDA has twice rejected J&J's bid to expand the label on Xarelto for ACS and has repeatedly informed the company that the additional data it has been re-filing has not been enough to allay fears over fatal bleeding. Panellist Steven Nissen of the Cleveland Clinic said at the meeting (and quoted by Bloomberg) that “it’s not just that the data are fragile, it’s that the therapy has both benefits and harms and in that context the quality of the data becomes increasingly important".

Xarelto is approved for six uses already in the USA - reducing the risk of strokes in patients with nonvalvular AF, as a treatment for deep vein thrombosis and pulmonary embolism and for reducing the risk of blood clots in the legs and lungs of people who have had hip or knee replacement surgery. It was approved in Europe for ACS in May last year.

Paul Burton, head of clinical development at J&J's Janssen R&D unit, said the company will "work with the FDA to address questions raised". The FDA approved Xarelto in July 2011 to prevent blood clots in patients undergoing knee and hip surgeries. The drug’s use has since been extended to patients with irregular heartbeats and deadly leg and lung blood clots.