The FDA’s Cardiovascular and Renal Drugs Advisory Committee voted 10-1 in favor of approval for the antiplatelet vorapaxar to reduce atherothrombotic events in patients with a history of MI.
Vorapaxar sulfate (proposed name Zontivity, Merck) plus aspirin has been shown to reduce the risk of cardiovascular events in atherosclerosis patients with no history of stroke or transient ischemia attack. But vorapaxar, a thrombin receptor antagonist, may hold bleeding risks.
Reviewers were asked to assess the tradeoff between the drug’s efficacy and risk. They weighed evidence from two randomized trials, TRAP2 and TRACER. TRAP2 enrolled 26,499 patients with either a prior MI, prior ischemic stroke or established peripheral artery disease. TRACER included almost 13,000 patients with acute coronary syndrome without STEMI within 24 hours of presenting at the hospital.
Both trials experienced setbacks. TRACER was terminated early because of major bleeding in the vorapaxar group. In TRAP2, study of patients with a history of stroke was terminated early while the other groups continued.
TRAP2 results showed vorapaxar reduced the risk of cardiovascular death, MI or stroke compared to placebo but the rate of bleeding was higher (1 percent vs. 0.5 percent).
The FDA takes the advisory panel’s recommendation into consideration when it makes its decision. It often but not always follows panel recommendations.