Comparison of Oral Anticoagulants for Extended VEnous Thromboembolism (COVET)
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ClinicalTrials.gov Identifier: NCT03196349 |
Recruitment Status :
Terminated
(Lack of enrollment)
First Posted : June 22, 2017
Results First Posted : August 14, 2019
Last Update Posted : December 13, 2019
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Venous Thromboembolism | Drug: Warfarin Drug: Apixaban 2.5 MG Drug: Rivaroxaban 10 MG | Phase 4 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 44 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Single (Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | Comparison of Oral Anticoagulants for Extended VEnous Thromboembolism (COVET) |
Actual Study Start Date : | August 1, 2018 |
Actual Primary Completion Date : | May 1, 2019 |
Actual Study Completion Date : | May 1, 2019 |

Arm | Intervention/treatment |
---|---|
Active Comparator: Warfarin
Subjects randomized to Warfarin will have warfarin administered daily in order to maintain a target INR of 2-3
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Drug: Warfarin
Will be randomized to receive open label warfarin daily to achieve a target INR of 2-3 |
Active Comparator: Apixaban
Subjects randomized to Apixaban will have apixaban administered study drug of 2.5mg twice daily
|
Drug: Apixaban 2.5 MG
Will be randomized to receive open label apixaban of 2.5 mg twice daily |
Active Comparator: Rivaroxaban
Subjects randomized to Rivaroxaban will have rivaroxaban administered study drug of 10 mg daily
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Drug: Rivaroxaban 10 MG
Will be randomized to receive open label rivaroxaban of 10mg daily |
- Number of Subjects With Clinically Relevant Bleeding Events [ Time Frame: Randomization to 12 months ]Primary outcome of Clinically relevant bleeding (composite of major bleeding (MB) and/or clinically relevant non major bleeding (CRNMB))
- Number of Subjects With Recurrent Venous Thromboembolism (VTE) [ Time Frame: Randomization to 12 months ]Primary efficacy outcome of recurrent VTE
- Number of Subjects Experiencing Major Bleeding [ Time Frame: Randomization to 12 months ]Major bleeding
- Number of Subjects Experiencing Clinically Relevant Non-major Bleeding [ Time Frame: Randomization to 12 months ]Clinically relevant non-major bleeding
- Number of Subjects With Premature Termination of Study Medication [ Time Frame: Randomization to 12 months ]Premature termination of study medication
- Number of Subjects Experiencing All-cause Mortality [ Time Frame: Randomization to 12 months ]All cause mortality
- Number of Subjects Experiencing Vascular Events (Myocardial Infarction, Ischemic Stroke) [ Time Frame: Randomization to 12 months ]MI, ischemic stroke, peripheral arterial embolism

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
3.1 Inclusion Criteria
To be eligible for this trial, patients must meet all of the following criteria:
- Have confirmed acute, symptomatic, first lower extremity proximal DVT and/or PE that is NOT associated with a transient risk factor.
- Have completed an initial treatment course of oral anticoagulant therapy for 3-12 months and have a recommendation from their provider to continue anticoagulation indefinitely.
- Have the capacity to understand and sign an informed consent form.
- Be 18 years of age and older.
- Under the direct care of a healthcare provider for treatment of VTE for the length of time in the study.
3.2 Exclusion Criteria
If a patient meets any of the following criteria, he or she may not be enrolled in the study:
- Creatinine clearance (CrCl) < 30 mL/min as determined by Cockcroft-Gault formula documented within 3 months from date of consent
- Significant liver disease (Child-Pugh B or C)
- Concomitant use of medications that are strong P-glycoprotein or CYP3A4 inducers/inhibitors
- Another indication for chronic therapeutic-dose anticoagulation, such as atrial fibrillation (i.e., rivaroxaban, 10 mg daily, or apixaban, 2.5 mg twice daily, would not be appropriate therapy)
- A clinical indication for a specific anticoagulant regimen (e.g., warfarin with a target INR of 2-3 is recommended for patients with 'triple-positive' antiphospholipid syndrome).
- Life expectancy < 3 months
- Currently pregnant or breast feeding
- Unable / unwilling to pay for one (or more) of the treatment options
- Active Cancer defined as:
Diagnosed with cancer within the past 6 months; or Recurrent, regionally advanced or metastatic disease; Currently receiving treatment or have received any treatment for cancer during the 6 months prior to randomization; or A hematologic malignancy not in complete remission
• Unwilling / unlikely to agree to follow up

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03196349
United States, California | |
University of California Irvine Medical Center | |
Orange, California, United States, 92868 |
Principal Investigator: | Thomas Ortel, MD | Duke University |
Documents provided by Duke University:
Responsible Party: | Duke University |
ClinicalTrials.gov Identifier: | NCT03196349 |
Other Study ID Numbers: |
Pro00077510 |
First Posted: | June 22, 2017 Key Record Dates |
Results First Posted: | August 14, 2019 |
Last Update Posted: | December 13, 2019 |
Last Verified: | December 2019 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Undecided |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Product Manufactured in and Exported from the U.S.: | No |
Thromboembolism Venous Thromboembolism Embolism and Thrombosis Vascular Diseases Cardiovascular Diseases Warfarin Rivaroxaban Apixaban |
Anticoagulants Factor Xa Inhibitors Antithrombins Serine Proteinase Inhibitors Protease Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action |