Person:

Morrow, David

Background: Vorapaxar is a protease‐activated receptor‐1 antagonist approved by the U.S. Food and Drug Administration (FDA) for the reduction of thrombotic cardiovascular (CV) events in patients with a history of myocardial infarction (MI) and peripheral artery disease (PAD), without a previous stroke or transient ischemic attack (TIA). Methods and Results: We examined the efficacy and safety of vorapaxar in the intended use population, considering 20 170 patients randomized in the multinational, double‐blinded, placebo‐controlled TRA 2°P‐TIMI 50 trial. Of these, 16 897 qualified with a history of MI in the prior 2 weeks to 1 year and 3273 with PAD. At baseline 97% of the patients were treated with aspirin, 71% with a thienopyridine, and 93% a statin. At 3 years, the endpoint of CV death, MI, or stroke was significantly reduced with vorapaxar compared with placebo (7.9% versus 9.5%, HR, 0.80; 95% CI 0.73 to 0.89; P<0.001). Vorapaxar also significantly reduced the composite of CV death, MI, stroke, and urgent coronary revascularization (10.1% versus 11.8%, HR, 0.83; 95% CI 0.76 to 0.90; P<0.001), as well as the rate of CV death or MI (P<0.001). The safety endpoint of GUSTO moderate or severe bleeding, was increased in the vorapaxar group (3.7 versus 2.4, HR, 1.55; 95% CI 1.30 to 1.86, P<0.001). Intracranial bleeding (ICH) was 0.6% versus 0.4%, P=0.10 with vorapaxar versus placebo, with fatal bleeding 0.2% versus 0.2%; P=0.70. Conclusions: In patients with prior MI or PAD who have not had a previous stroke or TIA, vorapaxar added to standard therapy is effective for long‐term secondary prevention of thrombotic CV events, while increasing moderate or severe bleeding. Clinical Trial Registration URL: clinicaltrials.gov Unique Identifier: NCT00526474.

OBJECTIVES: The purpose of this study was to assess the prognostic utility of lipoprotein(a) [Lp(a)] in individuals with coronary artery disease (CAD). BACKGROUND: Data regarding an association between Lp(a) and cardiovascular (CV) risk in secondary prevention populations are sparse. METHODS: Plasma Lp(a) was measured in 6,708 subjects with CAD from 3 studies; data were then combined with 8 previously published studies for a total of 18,978 subjects. RESULTS: Across the 3 studies, increasing levels of Lp(a) were not associated with the risk of CV events when modeled as a continuous variable (odds ratio [OR]: 1.03 per log-transformed SD, 95% confidence interval [CI]: 0.96 to 1.11) or by quintile (Q5:Q1 OR: 1.05, 95% CI: 0.83 to 1.34). When data were combined with previously published studies of Lp(a) in secondary prevention, subjects with Lp(a) levels in the highest quantile were at increased risk of CV events (OR: 1.40, 95% CI: 1.15 to 1.71), but with significant between-study heterogeneity (p = 0.001). When stratified on the basis of low-density lipoprotein (LDL) cholesterol, the association between Lp(a) and CV events was significant in studies in which average LDL cholesterol was ≥130 mg/dl (OR: 1.46, 95% CI: 1.23 to 1.73, p < 0.001), whereas this relationship did not achieve statistical significance for studies with an average LDL cholesterol <130 mg/dl (OR: 1.20, 95% CI: 0.90 to 1.60, p = 0.21). CONCLUSIONS: Lp(a) is significantly associated with the risk of CV events in patients with established CAD; however, there exists marked heterogeneity across trials. In particular, the prognostic value of Lp(a) in patients with low cholesterol levels remains unclear.

Background— Vorapaxar reduces cardiovascular death, myocardial infarction (MI), or stroke in patients with previous MI while increasing bleeding. Patients with diabetes mellitus (DM) are at high risk of recurrent thrombotic events despite standard therapy and may derive particular benefit from antithrombotic therapies. The Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-TIMI 50 trial was a randomized, double-blind, placebo-controlled trial of vorapaxar in patients with stable atherosclerosis. Methods and Results— We examined the efficacy of vorapaxar in patients with and without DM who qualified for the trial with a previous MI. Because vorapaxar is contraindicated in patients with a history of stroke or transient ischemic attack, the analysis (n=16 896) excluded such patients. The primary end point of cardiovascular death, MI, or stroke occurred more frequently in patients with DM than in patients without DM (rates in placebo group: 14.3% versus 7.6%; adjusted hazard ratio, 1.47; P<0.001). In patients with DM (n=3623), vorapaxar significantly reduced the primary end point (11.4% versus 14.3%; hazard ratio, 0.73 [95% confidence interval, 0.60–0.89]; P=0.002) with a number needed to treat to avoid 1 major cardiovascular event of 29. The incidence of moderate/severe bleeding was increased with vorapaxar in patients with DM (4.4% versus 2.6%; hazard ratio, 1.60 [95% confidence interval, 1.07–2.40]). However, net clinical outcome integrating these 2 end points (efficacy and safety) was improved with vorapaxar (hazard ratio, 0.79 [95% confidence interval, 0.67–0.93]). Conclusions— In patients with previous MI and DM, the addition of vorapaxar to standard therapy significantly reduced the risk of major vascular events with greater potential for absolute benefit in this group at high risk of recurrent ischemic events. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00526474.