Extended antiplatelet therapy with clopidogrel alone versus clopidogrel plus aspirin after completion of 9- to 12-month dual antiplatelet therapy for ACS patients with both high bleeding and ischemic risk. Rationale and design of the OPT-BIRISK double blinded, placebo controlled randomized trial

Abstract Background Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is the cornerstone for prevention ischemic events in patients with acute coronary syndromes (ACS) and undergoing percutaneous coronary intervention (PCI). However, the optimal antiplatelet strategy for ACS patients with both high bleeding and high ischemic risks is unclear. Study design The Optimal antiPlatelet Therapy for patients with high Bleeding and Ischemic RISK (OPT-BIRISK) trial is a multicenter, double blinded, placebo controlled, randomized study designed to test the superiority of extended antiplatelet therapy with clopidogrel monotherapy compared with aspirin and clopidogrel for reduction of bleeding events in ACS patients with both high bleeding and high ischemic risks (“bi-risk”). A total of 7700 patients who completed 9- to 12-month DAPT after new generation drug eluting stent implantation for the treatment of ACS will be randomized to receive clopidogrel monotherapy or aspirin plus clopidogrel for 9 months, followed by aspirin monotherapy for 3 months. The primary end point is Bleeding Academic Research Consortium type 2, 3 or 5 bleedings at 9 months after randomization. The key secondary endpoint is major adverse cardiac and cerebral events at 9 months after randomization, defined as a composite of all-cause death, myocardial infarction, stroke or coronary artery revascularization. Conclusion OPT-BIRISK is the first large scale, randomized trial aimed to explore the optimal antiplatelet strategy for bi-risk ACS patients after PCI in current clinical practice. The results will add evidence regarding de-escalation antiplatelet therapy for patients at special risk.