PAR-1 antagonists: current state of evidence

J Thromb Thrombolysis. 2013 Jan;35(1):1-9. doi: 10.1007/s11239-012-0752-4.

Abstract

Vorapaxar (SCH 530348) and atopaxar (E5555) are oral protease-activated receptor-1 (PAR-1) antagonists with high bioavailability. They inhibits thrombin induced platelet aggregation by competitively inhibiting PAR-1. We systematically evaluated the evidence for the efficacy and safety of all PAR-1 antagonists as well as for the individual drugs vorapaxar and atopaxar in different databases-PubMed, EMBASE, Scopus, and Cochrane register of Controlled Clinical Trials (CENTRAL).We selected randomized controlled trials of PAR-1 antagonists that reported on cardiovascular mortality as a clinical outcome. The random-effects Mantel-Haenszel model was used to evaluate the effect of PAR-1 antagonists on cardiovascular mortality. Seven trials were selected (N = 42,355) for analysis. PAR-1 antagonists as a class, as well as individually, were associated with a non-significant numerically lower risk of cardiovascular mortality than that seen with agents used in the control group; RR, 0.93; 95% CI, 0.83-1.04; P = 0.20). No heterogeneity was noted. However, PAR-1 antagonists also appeared to increase the risk of bleeding significantly. PAR-1 antagonists appear to be associated with some reduction in the risk of cardiovascular mortality; however the significantly higher bleeding risk noted with PAR-1 antagonists appear to mandate a very careful selection of patients that may benefit without a substantially increased risk of bleeds.

Publication types

  • Meta-Analysis
  • Review

MeSH terms

  • Coronary Artery Disease* / drug therapy
  • Coronary Artery Disease* / mortality
  • Hemorrhage* / chemically induced
  • Hemorrhage* / mortality
  • Humans
  • Imines* / adverse effects
  • Imines* / therapeutic use
  • Lactones* / adverse effects
  • Lactones* / therapeutic use
  • Platelet Aggregation Inhibitors* / adverse effects
  • Platelet Aggregation Inhibitors* / therapeutic use
  • PubMed
  • Pyridines* / adverse effects
  • Pyridines* / therapeutic use
  • Randomized Controlled Trials as Topic
  • Receptor, PAR-1 / antagonists & inhibitors*

Substances

  • E 5555
  • Imines
  • Lactones
  • Platelet Aggregation Inhibitors
  • Pyridines
  • Receptor, PAR-1
  • vorapaxar