Low-dose colchicine for the prevention of cardiovascular events after percutaneous coronary intervention: rationale and design of the COL BE PCI trial: Short title: Rationale and design of the COL BE PCI trial.

Patients with coronary artery disease (CAD) remain vulnerable to future major atherosclerotic events after revascularization, despite effective secondary prevention strategies. Inflammation plays a central role in the pathogenesis of CAD and recurrent events. To date, there is no specific anti-inflammatory medicine available with proven effective, cost-efficient, and favorable benefit-risk profile, except for colchicine. Initial studies with colchicine have sparked major interest in targeting atherosclerotic events with anti-inflammatory agents, but further studies are warranted to enforce the role of colchicine role as a major treatment pillar in CAD. Given colchicine's low cost and established acceptable long-term safety profile, confirming its efficacy through a pragmatic trial holds the potential to significantly impact the global burden of cardiovascular disease. The COL BE PCI trial is an investigator-initiated, multicenter, double-blind, event-driven trial. It will enroll 2,770 patients with chronic or acute CAD treated with percutaneous coronary intervention (PCI) at 19 sites in Belgium, applying lenient in- and exclusion criteria and including at least 30% female participants. Patients will be randomized between 2 hours and 5 days post-PCI to receive either colchicine 0.5 mg daily or placebo on top of contemporary optimal medical therapy and without run-in period. All patients will have baseline hsCRP measurements and a Second Manifestations of Arterial Disease (SMART) risk score calculation. The primary endpoint is the time from randomization to the first occurrence of a composite endpoint consisting of all-cause death, spontaneous non-fatal myocardial infarction, non-fatal stroke, or coronary revascularization. The trial is event-driven and will continue until 566 events have been reached, providing 80% power to detect a 21 % reduction in the primary endpoint taking a premature discontinuation of 15% into account. We expect a trial duration of approximately 44 months. The COL BE PCI Trial aims to assess the effectiveness and safety of administering low-dose colchicine for the secondary prevention in patients with both chronic and acute coronary artery disease undergoing PCI. Trial registration: ClinicalTrials.gov: NCT06095765.