Thrombin-receptor antagonist vorapaxar in acute coronary syndromes

N Engl J Med. 2012 Jan 5;366(1):20-33. doi: 10.1056/NEJMoa1109719. Epub 2011 Nov 13.

Abstract

Background: Vorapaxar is a new oral protease-activated-receptor 1 (PAR-1) antagonist that inhibits thrombin-induced platelet activation.

Methods: In this multinational, double-blind, randomized trial, we compared vorapaxar with placebo in 12,944 patients who had acute coronary syndromes without ST-segment elevation. The primary end point was a composite of death from cardiovascular causes, myocardial infarction, stroke, recurrent ischemia with rehospitalization, or urgent coronary revascularization.

Results: Follow-up in the trial was terminated early after a safety review. After a median follow-up of 502 days (interquartile range, 349 to 667), the primary end point occurred in 1031 of 6473 patients receiving vorapaxar versus 1102 of 6471 patients receiving placebo (Kaplan-Meier 2-year rate, 18.5% vs. 19.9%; hazard ratio, 0.92; 95% confidence interval [CI], 0.85 to 1.01; P=0.07). A composite of death from cardiovascular causes, myocardial infarction, or stroke occurred in 822 patients in the vorapaxar group versus 910 in the placebo group (14.7% and 16.4%, respectively; hazard ratio, 0.89; 95% CI, 0.81 to 0.98; P=0.02). Rates of moderate and severe bleeding were 7.2% in the vorapaxar group and 5.2% in the placebo group (hazard ratio, 1.35; 95% CI, 1.16 to 1.58; P<0.001). Intracranial hemorrhage rates were 1.1% and 0.2%, respectively (hazard ratio, 3.39; 95% CI, 1.78 to 6.45; P<0.001). Rates of nonhemorrhagic adverse events were similar in the two groups.

Conclusions: In patients with acute coronary syndromes, the addition of vorapaxar to standard therapy did not significantly reduce the primary composite end point but significantly increased the risk of major bleeding, including intracranial hemorrhage. (Funded by Merck; TRACER ClinicalTrials.gov number, NCT00527943.).

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Coronary Syndrome / drug therapy*
  • Acute Coronary Syndrome / therapy
  • Aged
  • Angioplasty
  • Cardiovascular Diseases / mortality
  • Cardiovascular Diseases / prevention & control
  • Combined Modality Therapy
  • Coronary Artery Bypass
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Follow-Up Studies
  • Hemorrhage / chemically induced*
  • Humans
  • Intracranial Hemorrhages / chemically induced
  • Kaplan-Meier Estimate
  • Lactones / adverse effects
  • Lactones / therapeutic use*
  • Male
  • Middle Aged
  • Platelet Aggregation Inhibitors / adverse effects
  • Platelet Aggregation Inhibitors / therapeutic use*
  • Pyridines / adverse effects
  • Pyridines / therapeutic use*
  • Receptor, PAR-1 / antagonists & inhibitors*

Substances

  • Lactones
  • Platelet Aggregation Inhibitors
  • Pyridines
  • Receptor, PAR-1
  • vorapaxar

Associated data

  • ClinicalTrials.gov/NCT00527943