Portola Pharmaceuticals Begins Enrollment In Phase 3 Trial For Andexanet Alfa

(RTTNews) - Portola Pharmaceuticals (PTLA) Monday said it has begun enrollment in a late-stage study for the recombinant Factor Xa inhibitor reversal agent andexanet alfa, with Bayer HealthCare and Janssen Pharmaceuticals Inc.'s Factor Xa inhibitor Xarelto.

Andexanet alfa is indicated for reversing the anticoagulation activity of Factor Xa inhibitor-treated patients who are experiencing a major bleeding episode or who require emergency surgery.

The randomized, double-blind, placebo-controlled Phase 3 study will test the efficacy of andexanet alfa in healthy volunteers aged 50 to 75. In the first part of the trial, around 40 healthy volunteers will be given Xarelto 20 mg once daily and then randomized in a 2:1 ratio to andexanet alfa administered as an 800 mg IV bolus or to placebo.

In the second part of the study, 40 healthy volunteers will be randomized in a 2:1 ratio to andexanet alfa administered as an IV bolus followed by a continuous infusion for 120 minutes or to placebo. The volunteers will be followed for up to 43 days to assess safety.