SOUTH SAN FRANCISCO, Calif., Feb. 10 /PRNewswire/ -- Portola Pharmaceuticals, Inc. today announced that results from its Phase 2 EXPLORE-Xa clinical trial of betrixaban, an investigational oral direct Factor Xa inhibitor anticoagulant, will be presented during a late-breaking results session at the American College of Cardiology's (ACC) 59th Annual Scientific Session in Atlanta in March. EXPLORE-Xa is a Phase 2 dose-ranging trial evaluating betrixaban for stroke prevention in 500 patients with atrial fibrillation (SPAF). Portola has a global development and commercialization agreement with Merck & Co., Inc. for betrixaban.

    Oral Presentation Details
    A Randomized Clinical Trial of Three Doses of a Long-Acting Oral Direct
     Factor Xa Inhibitor Betrixaban in Patients With Atrial Fibrillation
     (Presentation #3015-12)
    Presenter: Dr. Michael D. Ezekowitz
    Session: Late-Breaking Clinical Trials II: Cardiac Arrhythmias
    Date: Monday, March 15, 8:51-9:03 a.m. ET
    Location: Georgia World Congress Center, Murphy Ballroom

About Betrixaban

Betrixaban is an oral direct Factor Xa inhibitor anticoagulant with a half life that supports true, once-daily dosing and a low peak-to-trough drug concentration ratio that minimizes anticoagulant variability. Betrixaban has minimal excretion through the kidneys, and is the only novel anticoagulant currently being studied in patients regardless of their kidney function. As a result, it has the potential to become the only novel oral anticoagulant available for patients with severe renal disease. In addition, betrixaban is minimally metabolized through the Cytochrome P450 enzyme system, which may result in a low potential for drug-drug interactions.

Portola and Merck are currently evaluating betrixaban for SPAF in the EXPLORE-Xa trial. Betrixaban could potentially be further developed for other indications including, but not limited to, the treatment or prevention of life-threatening blood clots in patients undergoing high-risk orthopedic and general surgery, those with acute and chronic medical illness, and those with acute coronary syndrome.

About Portola Pharmaceuticals, Inc.

Portola Pharmaceuticals develops innovative therapeutics based on targets with established proofs of concept that are designed to provide significant advances over current treatments for cardiovascular disease and inflammation. The company has global development and commercialization agreements with two of the world's leading pharmaceutical companies collectively valued at about $1B in upfront and milestone payments plus double-digit royalties on future sales. Betrixaban, its oral direct Factor Xa inhibitor, is licensed to Merck & Co., Inc., and elinogrel, its competitive and reversible P2Y12 ADP receptor antagonist, is licensed to Novartis. Both are Phase 2 product candidates that have best-in-class features to address the global multi-billion dollar hospital, specialty and chronic care anticoagulant and antiplatelet markets, respectively. Portola's proprietary pipeline programs are focused on the discovery and development of PRT061103, a thromboxane receptor antagonist, which is targeted to address a significant unmet need as a potential aspirin alternative for patients intolerant to aspirin; PRT064445, a Factor Xa inhibitor antidote to help manage or reverse the bleeding complications in the tens of millions of patients expected to be treated with Factor Xa inhibitors or low-molecular weight heparin worldwide in the next decade; and PRT062607, a novel, orally-available Syk-specific kinase inhibitor to treat chronic inflammatory diseases, including rheumatoid arthritis. For additional information, visit www.portola.com.

SOURCE Portola Pharmaceuticals, Inc.