Colchicine in Patients Undergoing Coronary Artery Bypass Grafting After Acute Coronary Syndrome (COCAR)

Colchicine in Patients Undergoing Coronary Artery Bypass Grafting After Acute Coronary Syndrome: an Open-label Randomized Trial

The present study seeks to evaluate the effectiveness of the use of perioperative colchicine with regard to operative complications, in patients with acute coronary syndrome and indication for cardiac post-surgical revascularization.

Patients will be selected and randomized while still in the emergency room and medication (colchicine 0.5mg every 12 hours or placebo) will be started within 24 hours of randomization, being maintained for 30 days after surgery.

Study Overview

• Status: Completed
• Conditions: Coronary Artery Disease; Coronary Artery Bypass; Acute Coronary Syndrome; Postpericardiotomy Syndrome; Postoperative Atrial Fibrilation; Perioperative Myocardial Infarction; Myocardial Reperfusion
• Intervention / Treatment: Drug: Colchicine

Detailed Description

Atherosclerotic cardiovascular disease remains a leading cause of global morbidity and mortality. Despite advances in medical therapy, patients presenting with Acute Coronary Syndrome (ACS) sustain a high residual risk of recurrent events, largely driven by inflammatory pathways.

Consequently, targeting inflammation has become a major focus of recent cardiovascular research. Colchicine, a widely available and low-cost anti-inflammatory agent, has demonstrated significant benefits in both acute and chronic coronary syndromes. In the setting of elective coronary artery bypass grafting (CABG), prophylactic colchicine has been shown to reduce perioperative myocardial injury and the incidence of post-pericardiotomy syndrome, with a strong pathophysiological rationale for preventing postoperative atrial fibrillation (POAF).

However, evidence regarding the use of perioperative colchicine in the highly vulnerable scenario of patients presenting with ACS who require surgical revascularization (a "double inflammatory hit" model) is scarce. The present study seeks to evaluate the effectiveness of perioperative colchicine in preventing major operative complications in this specific high-risk ACS population. Objective documentation of the benefit of colchicine in this setting could pioneer a new therapeutic approach with great potential to modify current medical guidelines.

To address this gap, the trial utilizes a Prospective Randomized Open-label Blinded Endpoint (PROBE) design. While the allocation to the intervention (colchicine) or standard of care is open-label to both patients and the clinical care team, the assessment of all clinical endpoints is strictly masked.

To mitigate detection and observer bias, an independent Clinical Events Committee (CEC) was established. This committee is composed of physicians who are not involved in patient recruitment or direct clinical care. The CEC performs the formal, blinded adjudication of all clinical efficacy and safety events. The adjudication process is conducted using raw, anonymized clinical data (ECGs, cardiac biomarkers, surgical reports, and imaging), with the committee completely blinded to the randomized treatment allocation.

• Study Type: Interventional
• Enrollment (Actual): 100
• Phase: Phase 2

Contacts and Locations

Study Locations

• Brazil
  • São Paulo
    • São Paulo, São Paulo, Brazil, 05403000
      • Heart Institute - University of São Paulo

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients with acute coronary syndrome, with indication for myocardial revascularization surgery
• Patients of both genders, aged over 18 years.

Exclusion Criteria:

• Inability to sign the informed consent form;
• Current use of colchicine;
• Current use of long-term corticosteroid therapy
• Inflammatory bowel disease or chronic diarrhea;
• Clinically significant non-transient haematological abnormalities;
• Renal dysfunction, with creatinine greater than 2 times the upper limit of normality;
• Severe liver disease;
• Drug addiction or alcoholism;
• History of clinically significant sensitivity to colchicine.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Colchicine; Oral tablet colchicine 0.5mg, twice a day, will be started within 24 hours after randomization and maintained until 30 days after coronary artery bypass grafting.	Drug: Colchicine; Oral tablet colchicine 0.5mg, twice a day, will be started within 24 hours after randomization and maintained until 30 days after coronary artery bypass grafting.
No Intervention: Conventional treatment; The control group will follow conventional treatment guided by current guidelines.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Composite outcome of postpericardiotomy syndrome, postoperative fibrillation, and periprocedural myocardial infarction.	30 days after coronary artery bypass graft

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Death		30 days after coronary artery bypass graft
Myocardial infarction		30 days after coronary artery bypass graft
Stroke		30 days after coronary artery bypass graft
Hospital readmission		30 days after coronary artery bypass graft
Postpericardiotomy syndrome		30 days after coronary artery bypass graft
Postoperative fibrillation		30 days after coronary artery bypass graft
Periprocedural myocardial infarction		30 days after coronary artery bypass graft
Infection	Infection of any kind	30 days after coronary artery bypass graft
Myocardial injury		30 days after coronary artery bypass graft
Length of stay		30 days after coronary artery bypass graft

Collaborators and Investigators

• Sponsor: University of Sao Paulo General Hospital

Study record dates

Study Major Dates

• Study Start (Actual): February 5, 2022
• Primary Completion (Actual): December 21, 2025
• Study Completion (Actual): December 21, 2025

Study Registration Dates

• First Submitted: February 2, 2023
• First Submitted That Met QC Criteria: February 2, 2023
• First Posted (Actual): February 13, 2023

Study Record Updates

• Last Update Posted (Actual): March 3, 2026
• Last Update Submitted That Met QC Criteria: February 27, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Coronary Artery Disease; Atherosclerosis; Cardiac Surgery; Acute Coronary Syndrome; Colchicine; Cardiology; Myocardial Reperfusion; Postpericardiotomy Syndrome; Coronary Artery Bypass; Postoperative atrial fibrilation; Perioperative Myocardial Infarction
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Postoperative Complications; Pathologic Processes; Heart Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Myocardial Ischemia; Pathological Conditions, Signs and Symptoms; Coronary Artery Disease; Atherosclerosis; Acute Coronary Syndrome; Postpericardiotomy Syndrome; Heterocyclic Compounds; Alkaloids; Colchicine
• Other Study ID Numbers: SDC 5302/21/077

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No