Portola Pharmaceuticals, a biopharmaceutical company developing innovative drugs that provide significant advances in cardiovascular and inflammatory diseases, and cancer, announced new clinical data that demonstrate PRT060128, the Company's novel anti-platelet drug that directly and reversibly inhibits the P2Y12 ADP receptor, overcomes high platelet reactivity (HPR) in patients who do not respond to clopidogrel (Plavix(R)).

 

The results [Abstract #5603] were presented at the American Heart Association (AHA) Scientific Sessions 2008 in New Orleans, LA. Studies show there is substantial variability in patient response to clopidogrel therapy with up to 30% of patients not responding to treatment. Numerous studies link this suboptimal treatment response to poor clinical outcomes.

PRT060128 is the only reversible, direct acting, intravenous (IV) and oral ADP receptor antagonist in clinical development. Inhibiting the P2Y12 ADP receptor on platelets has been proven to prevent thrombosis and subsequent heart attacks. Portola believes that PRT060128 may provide significant clinical benefit through immediate, high-level platelet inhibition in the acute setting and a seamless transition to predictable, reversible platelet inhibition in the chronic setting.

"Of the millions of cardiac patients treated with clopidogrel anti- platelet therapy every year, a significant portion do not respond, and remain at high risk for major adverse cardiac events," said Paul A. Gurbel, M.D., principal investigator and Director of Cardiovascular Research at the Center for Thrombosis Research at Sinai Hospital, Baltimore, MD. "These results show that this direct-acting anti-platelet agent with a novel mechanism of action may have the potential to fill this significant treatment gap and meet a major unmet need."