FDA approves Boehringer's blood thinner reversal agent

By Ransdell Pierson (Reuters) - U.S. health regulators on Friday approved Praxbind, a reversal agent made by Germany's privately held Boehringer Ingelheim, for use in emergency situations by patients taking the company's widely used Pradaxa blood thinner. The Food and Drug Administration said it granted accelerated approval for Praxbind "for managing patients taking Pradaxa, in emergency or life-threatening situations when bleeding can’t be controlled.” The FDA in 2010 approved Pradaxa, a pill, to prevent stroke in patients with a common heart rhythm irregularity called atrial fibrillation. Although Pradaxa is highly effective at preventing blood clots that can cause strokes in such patients, until now there has been no way to reverse the drug's effects. Praxbind, an intravenous injection, is the first reversal agent approved specifically for Pradaxa and works by binding to the drug compound to neutralize it, the FDA said. Another company is working on a reversal agent for two other leading oral blood thinner drugs. Portola Pharmaceuticals Inc plans before the end of 2015 to seek FDA approval for its agent that has proven highly able to reverse the effects of Johnson & Johnson's Xarelto and Eliquis from Bristol-Myers Squibb and Pfizer Inc. As blood thinners, Pradaxa, Xarelto and Eliquis are all meant to be more convenient alternatives to warfarin, an oral anti-coagulant that has been sold for more than 60 years but which comes with serious bleeding risks, difficult dietary restrictions and the need for routine blood monitoring. Vitamin K is often used to reverse the effects of warfarin, when bleeding emergencies occur. Xarelto and Eliquis, approved in 2011 and 2012, respectively, each have annual sales of about $1.6 billion and thin the blood by blocking Factor Xa, a protein highly involved in the blood-clotting process. Pradaxa, which had 2014 sales of $1.3 billion, works by directly blocking a clotting protein called thrombin. The drug's sales have stagnated due to safety concerns, including elevated risk of gastrointestinal bleeding. Last year, Boehringer paid $650 million to settle claims in the United States that Pradaxa had caused severe and fatal bleeding. (Reporting by Ransdell Pierson; Editing by Leslie Adler)