The Peri-OPerative COlchicine to Reduce Negative Events (POPCORN) Trial

Patients with prior coronary revascularization have a high risk of major adverse cardiovascular events (MACE) after major surgery, up to more than 2-fold when compared to patients without prior coronary revascularization. The pro-inflammatory and hypercoagulable states induced by surgery and the hemodynamic changes caused by fluid shifts and anesthesia are all important triggers of perioperative myocardial ischemia. Indeed, peri-operative systemic inflammation is associated with a nearly 4-fold increase in the risk of perioperative MACE. Neutrophils, the most abundant of inflammatory cells, adhere to inflamed or injured endothelium, migrate into the vessel wall, release proteolytic enzymes that can lead to erosion or rupture of plaque. Peri-operative cytokine generation may also activate the inflammasome and, thereby, macrophage-mediated synthesis of interleukin (IL)-1 , a known target for therapy for secondary prevention of MACE, particularly in the setting of high C-reactive protein (CRP) concentration.

Colchicine is a safe, well-tolerated anti-inflammatory agent that preferentially accumulates in neutrophils compared with other inflammatory cells. Colchicine inhibits chemotaxis, endothelial adhesion, and extravasation of neutrophils at sites of endothelial injury or inflammation; suppresses the inflammasome-mediated production of IL-1 by macrophages; and reduces inflammation and MACE in patients with cardiovascular disease. The Colchicine Cardiovascular Outcomes Trial and Low Dose Colchicine 2 Trial demonstrated a reduction in MACE with colchicine in about 4000 patients with prior myocardial infarction and about 5000 patients with stable coronary artery disease, respectively. The Colchicine-PCI trial demonstrated for the first time that administration of colchicine prior to injury dampens the inflammatory response measured by CRP. The effects of colchicine on peri-operative MACE in patients with prior coronary revascularization or high coronary atherosclerotic burden undergoing major surgery, remains unknown.

The aims of this trial are to 1) assess the effect of colchicine compared to placebo on peri-operative MACE in response to intermediate- or high-risk non-cardiac surgery in patients with prior coronary revascularization or high coronary atherosclerotic burden; 2) characterize the level of systemic inflammation and profile of peri-operative neutrophils in this population; and 3) determine the clinical and genetic predictors of peri-operative MACE and examine factors that determine heterogeneity of treatment response in this population. This prospective, double-blinded, placebo-controlled, randomized trial will enroll 700 participants with prior coronary revascularization or high coronary atherosclerotic burden who undergo intermediate- or high-risk non-cardiac surgery across six VA medical centers that serve as cardiovascular referral centers for their VISNs. Following referral for surgery, and confirmation that the patient meets all study entry criteria, participants will be consented and randomized 1:1 within center to a loading dose of colchicine or placebo one day before surgery and twice daily dosing for 14 days post-operation. DNA will be collected at baseline, while measures of systemic inflammation will be collected at baseline, one day, two days, and at 14 days post-operation (or hospital discharge, whichever occurs earlier). Follow-up for all randomized participants who undergo surgery will occur at 30 days + 7 days.