Colchicine to Quench the Inflammatory Response After Deep Vein Thrombosis (The Conquer-DVT Pilot Trial)

Eligible and consenting patients will be randomized via a central web-based randomization system (1:1 ratio) to receive one tablet of colchicine 0.5 mg or identical matching placebo daily starting within 7 days of initiation of anticoagulation for acute, symptomatic, proximal lower extremity Deep Vein Thrombosis (DVT) for a treatment course of 180 days (+/- 7 days). Study drug will start within 24 hours of randomization. The type, dose, and duration of anticoagulant therapy : unfractionated heparin, Low Molecular Weight Heparin (LMWH), fondaparinux, Direct Oral Anticoagulation (DOAC) or Vitamin K Agonist (VKA) will be left to the discretion of the treating physician or local investigator. The study drug will be continued until the end of the treatment period (180 days +/- 7 days). All patients will be observed until the end of study follow-up (365 days +/- 7 days).

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

• History of an allergic reaction or significant sensitivity to colchicine.
• Requirement of colchicine for other indications.
• 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.
• Known or suspected, recent (<30 days) or active infections (acute or chronic).
• History of cirrhosis, chronic active hepatitis, or severe liver disease.
• Recent (<30 days) or chronic use of systemic (oral, intravenous) immunosuppressive drugs (including but not limited to steroids, tumor necrosis factor-alpha blockers, cyclosporine).
• Known active cancer.
• 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.
• Pregnancy, breast feeding or may be considering pregnancy during the study period or women of childbearing potential unwilling to use appropriate contraception during sex;
• The use of medication with known drug-to-drug interactions (including but not limited to erythromycin or clarithromycin).
• Unable or unwilling to provide consent.