Positive results with Portola’s anti-clotting agent andexanet alfa and Eliquis

Portola Pharmaceuticals (Nasdaq: PTLA) says that its first Phase III study of andexanet alfa, a potential universal Factor Xa inhibitor antidote and US Food and Drug Administration-designated breakthrough therapy, met its primary and secondary endpoints with high statistical significance. Portola’s share shot up 16.1% to $29.35 on the news.

Andexanet alfa was well tolerated with no serious adverse events reported. Top-line efficacy data from the first of two ANNEXA-A (Andexanet Alfa a Novel Antidote to the Anticoagulant Effects of fXA Inhibitors - Apixaban) studies demonstrated that an intravenous (IV) bolus of andexanet alfa immediately and significantly reversed the anticoagulation activity of US pharma majors Bristol-Myers Squibb (NYSE: BMY) and Pfizer (NYSE: PFE) direct Factor Xa inhibitor Eliquis (apixaban).

Detailed data will be presented as an oral presentation during the Clinical Science: Special Report session at the American Heart Association 2014 Scientific Sessions on Monday, November 17.