Vorapaxar: Phase III data

Top-line data from the double-blind, international Phase III TRA-2P trial in 26,449 patients showed that vorapaxar plus standard of care (SOC) met the composite primary endpoint of significantly reducing the incidence of cardiovascular death, MI, stroke or urgent coronary revascularization vs. placebo plus SOC. Merck did say the vorapaxar arm led to a significant increase in bleeding, including intracranial hemorrhage, vs. the placebo arm, but that the risk of intracranial hemorrhage was lower in patients without a history of stroke. The trial enrolled patients with a prior heart attack, ischemic stroke or peripheral arterial disease (PAD) to receive placebo or once-daily 2.5 mg vorapaxar in combination with SOC consisting of clopidogrel or aspirin. Data will be presented at the American College of Cardiology meeting in Chicago in March. Merck said it will review data from both the TRA-2P and TRACER trials in order to better understand the product profile of vorapaxar in specific patient populations and to determine next steps, including potential regulatory filings.

Last November, Merck reported data from the Phase III TRACER trial in 12,944 patients with non-ST segment elevation acute coronary syndrome (ACS) showing that vorapaxar plus SOC missed the composite primary endpoint of significantly reducing the incidence of cardiovascular death, MI, stroke, recurrent ischemia with rehospitalization or urgent coronary revascularization after a median follow-up of 502 days vs. placebo plus SOC (18.5% vs. 19.9%, p=0.07). In TRACER, vorapaxar plus SOC significantly reduced the composite secondary endpoint of the incidence of CV death, MI or stroke vs. placebo plus SOC (14.7% vs. 16.4%, p=0.02). However, Merck said that according to the pre-specified data analysis plan, superiority for the composite secondary endpoint could not be declared because the primary endpoint was not achieved (see BioCentury, Nov. 21, 2011). ...