Betting on best, not first

Portola Pharmaceuticals Inc. and partner Merck & Co. Inc. have reached the threshold of Phase III for betrixaban in the race to replace warfarin, but with three pharma compounds ahead of it, betrixaban will be selling a best-in-class story in the atrial fibrillation space.

In Phase IIb data presented at this month's American College of Cardiology meeting in Atlanta, Portola's once-daily, oral Factor Xa inhibitor showed improved safety over warfarin, which is associated with major bleeding, as well as unpredictable kinetics and interactions with other medications and even food. The study wasn't powered to show significance on efficacy endpoints...