Efficacy and Safety of Ticagrelor Over Time in Patients With Prior MI in PEGASUS-TIMI 54

Abstract

Background: Ticagrelor reduces ischemic risk in patients with prior myocardial infarction (MI). It remains unclear whether ischemic risk and the benefits of prolonged P2Y₁₂ inhibition in this population remain consistent over time.

Objectives: The study sought to investigate the pattern of ischemic risk over time and whether the efficacy and safety of ticagrelor were similar early and late after randomization.

Methods: The PEGASUS-TIMI (Prevention of Cardiovascular Events in Patients with Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin-Thrombolysis In Myocardial Infarction) 54 trial randomized patients with prior MI (median 1.7 years prior) to ticagrelor 90 mg, ticagrelor 60 mg, or placebo on a background of aspirin. The rates of cardiovascular (CV) death, MI, and stroke as well as TIMI major bleeding were analyzed at yearly landmarks (years 1, 2, and 3).

Results: A total of 21,162 patients were randomized and followed for 33 months (median), with 28% of patients ≥5 years from MI at trial conclusion. The risk of CV death, MI, or stroke in the placebo arm remained roughly constant over the trial at an ∼3% annualized rate. The benefit of ticagrelor 60 mg was consistent at each subsequent landmark (year 1 hazard ratio [HR]: 0.82; 95% confidence interval [CI]: 0.67 to 0.99; year 2 HR: 0.90; 95% CI: 0.74 to 1.11; and year 3 HR: 0.79; 95% CI: 0.62 to 1.00). TIMI major bleeding was increased with ticagrelor 60 mg at each landmark, but with the greatest hazard in the first year (year 1 HR: 3.22; year 2 HR: 2.07; year 3 HR: 1.65).

Conclusions: Patients with a history of MI remain at persistent high risk for CVD, MI, and stroke as late as 5 years after MI. The efficacy of low-dose ticagrelor is consistent over time with a trend toward less excess bleeding. (Prevention of Cardiovascular Events in Patients with Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin [PEGASUS]; NCT01225562).

Keywords: P2Y(12) inhibition; cardiovascular death; ischemic risk; myocardial infarction; secondary prevention; stroke.