FDA Agrees to Review Antithrombotic Drug Vorapaxar
Approval sought for secondary prevention of cardiovascular events (July 24)
A new drug application (NDA) for an investigational antithrombotic medicine, vorapaxar, has been accepted for standard review by the FDA.
The drug’s developer (Merck) is seeking approval of vorapaxar for the secondary prevention of cardiovascular events in patients with a history of heart attack and no history of stroke or transient ischemic attack (TIA).
Vorapaxar is an antagonist of the protease-activated receptor-1 (PAR-1) — the primary receptor for thrombin on human platelets that is also present on vascular endothelium and smooth muscle. Patients with peripheral artery disease (PAD) are at risk of systemic atherothrombotic events as well as acute and chronic limb ischemia.
In the large randomized, double-blind, placebo-controlled TRA2°P-TIMI 50 trial, which included 26,449 patients with stable atherosclerotic vascular disease (i.e., myocardial infarction [MI], stroke, or PAD), vorapaxar did not reduce the risk of cardiovascular death, MI, or stroke in patients with PAD; however, the drug significantly reduced acute limb ischemia and peripheral revascularization. The beneficial effects of PAR-1 antagonism on limb vascular events were accompanied by an increased risk of bleeding.
According to Reuters, if the drug is approved, it would likely be used by few patients because of the bleeding risk.