Colchicine to reduce inflammation after proximal deep vein thrombosis

Colchicine to Quench the Inflammatory Response After Deep Vein Thrombosis: A Randomized Controlled Pilot Trial

This trial will try daily low‑dose colchicine (0.5 mg) versus a matching placebo in adults with a first proximal lower‑leg DVT to see if it lowers the chance of developing post‑thrombotic syndrome.

Quick facts

• Phase: Phase 3
• Study type: Interventional
• Enrollment: 150 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Ottawa Hospital Research Institute (Academic / other)
• Locations: 3 sites (Ottawa, Ontario and 2 other locations)
• Trial ID: NCT06440694 on ClinicalTrials.gov

What this trial studies

This is a double‑blind, randomized (1:1), placebo‑controlled pilot trial testing colchicine 0.5 mg daily started within seven days of initiating anticoagulation for acute, symptomatic proximal lower‑extremity DVT. Participants receive study drug for 180 days (+/‑ 7 days) with clinical follow‑up continued to 365 days (+/‑ 7 days); anticoagulant type and dosing are determined by the treating clinician. Randomization is central and web‑based and study drug begins within 24 hours of randomization. The pilot is designed to test feasibility and gather preliminary data to inform a potential full‑scale Phase 3 trial.

Who should consider this trial

Good fit: Adults (≥18) with a first, acute, symptomatic proximal (popliteal vein or above) objectively confirmed lower‑extremity DVT who can start the study drug within seven days of beginning anticoagulation and agree to one year of follow‑up.

Not a fit: Patients with active cancer, severe liver disease, active or recent infections, inflammatory bowel disease or chronic diarrhea, blood dyscrasias, current need for colchicine, or recent systemic immunosuppression are excluded and therefore unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, colchicine could lower the risk of post‑thrombotic syndrome after proximal DVT, reducing long‑term leg pain, swelling, and disability.

How similar studies have performed: Low‑dose colchicine has shown benefit in reducing inflammation and adverse outcomes in cardiovascular disease trials, but using colchicine specifically to prevent post‑thrombotic syndrome after DVT is novel and not yet proven in large trials.

Eligibility criteria

Inclusion Criteria:

* Consenting patients 18 years of age or older with a first, acute, symptomatic proximal (popliteal vein or more proximal) objectively confirmed DVT of the lower extremity will be eligible to participate in the study.

Exclusion Criteria:

1. History of an allergic reaction or significant sensitivity to colchicine.
2. Requirement of colchicine for other indications.
3. Active or chronic diarrhea, or documented inflammatory bowel disease (i.e., Crohn's disease or ulcerative colitis), collagenous colitis or irritable bowel syndrome or existing blood dyscrasias.
4. Known or suspected, recent (\<30 days) or active infections (acute or chronic).
5. History of cirrhosis, chronic active hepatitis, or severe liver disease.
6. Recent (\<30 days) or chronic use of systemic (oral, intravenous) immunosuppressive drugs (including but not limited to steroids, tumor necrosis factor-alpha blockers, cyclosporine).
7. Known active cancer.
8. Any of the following as measured within the past 1-3 months or at screening: alanine, or aspartate aminotransferase \>3 times the upper limit of normal, total bilirubin \>2 times the upper limit of normal and a creatinine clearance by Cockcroft-Gault formula \<30 mL/min.
9. Pregnancy, breast feeding or may be considering pregnancy during the study period or women of childbearing potential unwilling to use appropriate contraception during sex;
10. The use of medication with known drug-to-drug interactions (including but not limited to erythromycin or clarithromycin).
11. Unable or unwilling to provide consent.

Where this trial is running

Ottawa, Ontario and 2 other locations

• The Ottawa Hospital General Campus — Ottawa, Ontario, Canada (Recruiting)
• Centre de recherche du Centre hospitalier de l'Université de Montréal — Montreal, Quebec, Canada (Recruiting)
• The Sir Mortimer B. Davis Jewish General Hospital — Montreal, Quebec, Canada (Not_yet_recruiting)

Study contacts

• Principal investigator: Marc Carrier, MD,MSc,FRCPC — Ottawa Hospital Research Institute / Division of Hematology- The Ottawa Hospital
• Study coordinator: Marc Carrier, MD,MSc,FRCPC

Conditions Venous Thromboembolism; Proximal Lower Extremity Deep Vein Thrombosis; Randomized Trial; Colchicine; Post Thrombotic Syndrome; Inflammation