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

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

This trial seeks to assess the feasibility of a full-scale, double-blind, placebo-controlled, randomized trial assessing whether low-dose colchicine (0.5 mg daily) reduces the risk of post-thrombotic syndrome (PTS) in patients with proximal lower extremity deep vein thrombosis (DVT).

Study Overview

• Status: Recruiting
• Conditions: Venous Thromboembolism
• Intervention / Treatment: Drug: Colchicine 0.5 mg po; Drug: Placebo 0.5 mg po

Detailed Description

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).

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Marc Carrier, MD,MSc,FRCPC; Phone Number: Ext. 73668 6137378899; Email: mcarrier@toh.ca

Study Locations

• Canada
  • Ontario
    • Ottawa, Ontario, Canada, K1H 8L6
      • Recruiting
      • The Ottawa Hospital General Campus
      • Contact: Veronica Bates; Email: vebates@ohri.ca
      • Principal Investigator: Marc Carrier, MD,MSc,FRCPC
  • Quebec
    • Montreal, Quebec, Canada, H2X 0A9
      • Recruiting
      • Centre de recherche du Centre Hospitalier de l'Universite de Montreal
      • Contact: Amélie Martin; Phone Number: 31541 514-890-8000; Email: amelie.martin.chum@ssss.gouv.qc.ca
      • Principal Investigator: Emmanuelle Duceppe, MD,PhD,FRCPC
    • Montreal, Quebec, Canada, H3T 1E2
      • Not yet recruiting
      • The Sir Mortimer B. Davis Jewish General Hospital
      • Contact: Stephanie Scala; Phone Number: 22178 514-340-8222; Email: Stephanie.Scala@ladydavis.ca
      • Principal Investigator: Susan Kahn, MD,MSc,FRCPC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental Arm: Colchicine; Colchicine 0.5 mg po once daily for 180 days. After the Day - 180 follow up, the study treatment will be discontinued and subsequent treatment will be at the discretion of the attending physician.	Drug: Colchicine 0.5 mg po; Colchicine 0.5 mg po once daily for 180 days.; Other Names: Myinfla tablet 0.5 mg po daily
Placebo Comparator: Control Arm : Placebo; Placebo 0.5 mg po once daily for 180 days. After the Day - 180 follow up, the study treatment will be discontinued and subsequent treatment will be at the discretion of the attending physician.	Drug: Placebo 0.5 mg po; Placebo 0.5 mg po once daily for 180 days.; Other Names: Placebo 0.5 mg po daily

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pilot Trial Primary Outcome: Recruitment Rate	Mean number of participants recruited per site per month	12 months
Full-Scale Trial Primary Outcome: Post Thrombotic Syndrome	VILLALTA scale score ≥5 signifies clinically meaningful Post Thrombotic Syndrome	180 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pilot Trial Secondary Outcome: Eligibility Rate	Proportion of screened patients who are eligible	12 months
Pilot Trial Secondary Outcome: Consent Rate	Proportion of eligible patients who provide consent	12 months
Pilot Trial Secondary Outcome: Retention Rate	Proportion of participants retained at follow-up	12 months
Pilot Trial Secondary Outcome: Study Completion Rate	Proportion of participants who completed all study procedures	12 months
Pilot Trial Secondary Outcome: Adherence Rate	Adherence to study drug measured by pill count at the end of follow-up	12 months
Pilot Trial Secondary Outcome: Reasons for declining participation	Pilot Trial Secondary Outcome: Reasons for declining participation	12 months
Full-Scale Trial Secondary Outcome: Recurrent Venous Thromboembolism	Full-Scale Trial Secondary Outcome: Recurrent Venous Thromboembolism	180 and 365 days
Full-Scale Trial Secondary Outcome: Major Bleeding	As per International Society on Thrombosis and Haemostasis (ISTH) definition	180 and 365 days
Full-Scale Trial Secondary Outcome: Clinically Relevant Non-Major Bleeding	As per ISTH definition	180 and 365 days
Full-Scale Trial Secondary Outcome: Overall Mortality	Full-Scale Trial Secondary Outcome: Overall Mortality	180 and 365 days
Full-Scale Trial Secondary Outcome: Incremental Cost-Effectiveness Ratio (ICER)	Full-Scale Trial Secondary Outcome: Incremental Cost-Effectiveness Ratio (ICER)	180 and 365 days
Full-Scale Trial Secondary Outcome: Post Thrombotic Syndrome	VILLALTA scale score ≥5 signifies clinically meaningful Post Thrombotic Syndrome	365 days
Full-Scale Trial Secondary Outcome: Severe Post Thrombotic Syndrome	VILLALTA scale score ≥ 15 signifies significant clinically meaningful Post Thrombotic Syndrome or presence of ulcer will be collected	180 and 365 days
Full-Scale Trial Secondary Outcome: Severity of Post Thrombotic Syndrome	Continuous VILLALTA score (VILLALTA scale score ≥5 signifies clinically meaningful Post Thrombotic Syndrome)	180 and 365 days
Full-Scale Trial Secondary Outcome: Patient Reported VILLALTA Scale	Full-Scale Trial Secondary Outcome: Patient Reported VILLALTA Scale (VILLALTA scale score ≥5 signifies clinically meaningful Post Thrombotic Syndrome)	180 and 365 days
Full-Scale Trial Secondary Outcome: Venous disease Specific Quality of Life	Scoring using VEINES-QOL/Sym (The VEINES-QOL summary score (based on 25 items) estimates the impact of chronic venous disease upon QOL)	180 and 365 days
Full-Scale Trial Secondary Outcome: Health-Related Quality of Life	Scoring using EuroQoL-EQ-5D-5L (EQ-5D-5L index scores range from -0.59 to 1, where 1 is the best possible health state)	180 and 365 days

Collaborators and Investigators

• Sponsor: Ottawa Hospital Research Institute
• Investigators: Principal Investigator: Marc Carrier, MD,MSc,FRCPC, Ottawa Hospital Research Institute / Division of Hematology- The Ottawa Hospital

Study record dates

Study Major Dates

• Study Start (Actual): July 7, 2025
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: May 28, 2024
• First Submitted That Met QC Criteria: May 28, 2024
• First Posted (Actual): June 4, 2024

Study Record Updates

• Last Update Posted (Actual): December 30, 2025
• Last Update Submitted That Met QC Criteria: December 23, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Inflammation; Colchicine; Randomized Trial; Post Thrombotic Syndrome; Proximal Lower Extremity Deep Vein Thrombosis
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Embolism and Thrombosis; Venous Insufficiency; Thromboembolism; Venous Thrombosis; Thrombosis; Pathological Conditions, Signs and Symptoms; Inflammation; Postthrombotic Syndrome; Venous Thromboembolism; Heterocyclic Compounds; Alkaloids; Colchicine
• Other Study ID Numbers: CONQUER-DVT Pilot

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: To be developed
• IPD Sharing Time Frame: Upon completion of the full-scale trial
• IPD Sharing Access Criteria: Contact Principal Investigator
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No