Merck announces top-line results of TRA-2P study of Vorapaxar

Merck (NYSE:MRK), known outside the United States and Canada as MSD, today announced the top-line results of the TRA-2P (Thrombin Receptor Antagonist in Secondary Prevention of atherothrombotic ischemic events) study of vorapaxar. Merck is developing vorapaxar, an investigational oral Protease Activated Receptor 1 (PAR-1) thrombin receptor antagonist, for the prevention of thrombosis, or clot formation, and the reduction of cardiovascular events.

TRA-2P showed that the addition of vorapaxar to standard of care significantly reduced the risk of the protocol-specified primary endpoint of the composite of cardiovascular death (CVD), heart attack (myocardial infarction, or MI), stroke or urgent coronary revascularization compared to standard of care. There was a significant increase in bleeding, including intracranial hemorrhage (ICH), among patients taking vorapaxar in addition to standard of care, although there was a lower risk of ICH in patients without a history of stroke.

The full results of TRA-2P will be presented at the American College of Cardiology Scientific Sessions in March.

“In developing vorapaxar, Merck and our scientific collaborators set a very high bar – would the addition of vorapaxar to standard of care provide incremental benefit in preventing clots?” said Peter S. Kim, president, Merck Research Laboratories. “We are pleased that TRA-2P met its primary endpoint, and we look forward to discussing the results with the scientific community.”

Merck will review the data from both TRA2-P and TRACER with the investigators and other outside experts to help better understand the profile of this investigational medicine in specific patient populations and to determine next steps, including potential regulatory filings.

Vorapaxar has been evaluated in two major clinical outcomes studies: TRA-2P TIMI 50 (Clinicaltrials.gov identifier: NCT00526474 ) was led by the Thrombolysis in Myocardial Infarction (TIMI) Study Group of Brigham and Women’s Hospital. TRA-2P was a secondary prevention study in 26,449 patients with a heart attack, an ischemic stroke, or documented peripheral vascular disease. TRACER (Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome), (Clinicaltrials.gov identifier: NCT00527943) was an acute care, hospital-based study of approximately 12,944 patients with non-ST-segment-elevation acute coronary syndrome. The study was led by the Duke Clinical Research Institute, and results were presented in 2011 at the American Heart Association Scientific Sessions and published in the January 5, 2012 issue of The New England Journal of Medicine (Vol. 366, No. 1). The news release can be found at http://www.merck.com/newsroom/news-release-archive/research-and-development/2011_1113.html.