Positive top-line results for Portola’s blood-thinner antidote

USA-based Portola Pharmaceuticals (Nasdaq: PTLA) has released positive top-line results from the second part of the Phase III ANNEXA-A (Andexanet Alfa a Novel Antidote to the Anticoagulant Effects of FXa Inhibitors – Apixaban) study. This evaluated the safety and efficacy of andexanet alfa, an investigational antidote, with Bristol-Myers Squibb’s (NYSE: BMY) Factor Xa inhibitor Eliquis (apixaban) in healthy volunteers.

Andexanet alfa, a US Food and Drug Administration-designated Breakthrough Therapy, was administered as an intravenous (IV) bolus followed by a continuous two-hour infusion to sustain the reversal of anticoagulation activity. This registration-enabling study achieved all primary and secondary endpoints with high statistical significance. Andexanet alfa produced rapid reversal of the anticoagulant effect of apixaban, as measured by anti-Factor Xa activity, which was sustained for the duration of the infusion. In the study, andexanet alfa was well tolerated, with no serious adverse events, thrombotic events, or antibodies to Factor X or Xa reported. The full data from this second part of the ANNEXA-A study will be presented at an upcoming scientific meeting.

Plans to submit BLA by end of 2015