The Phase II trial, called Explore Xa, is a multi-national, double-blind, dose-finding study that will enroll approximately 500 patients and assess three once-daily doses of betrixaban (40mg, 60mg, and 80mg) administered for at least three months compared to dose-adjusted warfarin (given open label), the current standard of care, in patients with non-valvular atrial fibrillation.
The goal of the study is to assess long-term safety and tolerability of betrixaban and provide key dosing information for Phase III studies. The company expects to complete enrollment of this trial by the end of 2009.
Charles Homcy, president and CEO of Portola, said: “This is a major milestone achievement to advance the first of our two highly differentiated Phase II product candidates that address the unmet needs of the more than 50 million patients worldwide requiring hospital or chronic antithrombotic therapy.”