Early Withdrawal of Aspirin after PCI in Acute Coronary Syndromes

BACKGROUND: Whether potent P2Y12 inhibitor monotherapy without aspirin initiated shortly after successful percutaneous coronary intervention (PCI) is effective and safe for patients with acute coronary syndromes is unclear. METHODS: We conducted a multicenter, open-label, randomized trial in Brazil involving patients with acute coronary syndromes who had undergone successful PCI. Patients were assigned in a 1:1 ratio within the first 4 days of hospitalization to stop treatment with aspirin and receive potent P2Y12 inhibitor monotherapy (ticagrelor or prasugrel) or to receive dual antiplatelet therapy (aspirin and a potent P2Y12 inhibitor) for 12 months. The two ranked primary outcomes, assessed through 12 months, were a composite of death from any cause, myocardial infarction, stroke, or urgent target-vessel revascularization (tested for noninferiority, with a noninferiority margin of 2.5 percentage points) and major or clinically relevant nonmajor bleeding (tested for superiority). RESULTS: A total of 3410 patients were included in the intention-to-treat population (1712 in the monotherapy group and 1698 in the dual antiplatelet therapy group). At 12 months, death from any cause, myocardial infarction, stroke, or urgent revascularization had occurred in 119 patients (Kaplan-Meier estimate, 7.0%) in the monotherapy group and in 93 patients (Kaplan-Meier estimate, 5.5%) in the dual antiplatelet therapy group (absolute risk difference, 1.47 percentage points; 95% confidence interval [CI], -0.16 to 3.10; P = 0.11 for noninferiority). Major or clinically relevant nonmajor bleeding had occurred in 33 patients (Kaplan-Meier estimate, 2.0%) in the monotherapy group and in 82 patients (Kaplan-Meier estimate, 4.9%) in the dual antiplatelet therapy group (absolute risk difference, -2.97 percentage points; 95% CI, -4.20 to -1.73). Stent thrombosis occurred in 12 patients in the monotherapy group and in 4 in the dual antiplatelet therapy group. CONCLUSIONS: Among patients who had undergone successful PCI for acute coronary syndromes, potent P2Y12 inhibitor monotherapy was not found to be noninferior to dual antiplatelet therapy with respect to a composite of death or ischemic events at 12 months. (Funded by the Brazilian Ministry of Health; NEO-MINDSET ClinicalTrials.gov number, NCT04360720.).