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Anticoagulant

Rivaroxaban vs Apixaban for Blood Clots (COBRRA Trial)

Vancouver, Canada
Phase 4
Recruiting
Led By Lana Castellucci, MD, FRCPC
Research Sponsored by Ottawa Hospital Research Institute
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Age ≥ 18 years old
Confirmed newly diagnosed symptomatic acute venous thromboembolism (VTE) [proximal lower extremity deep vein thrombosis (DVT) or segmental or greater pulmonary embolism (PE)]
Must not have
Have received > 72 hours of therapeutic anticoagulation
Contraindication for anticoagulation with apixaban or rivaroxaban as determined by the treating physician such as, but not limited to: active bleeding, active malignancy, weight > 120 kg, liver disease (Child-Pugh Class B or C), use of contraindicated medications, another indication for long-term anticoagulation (e.g. atrial fibrillation), pregnant (note below) or breastfeeding (Note: as reported by the patient or a pregnancy test will be ordered at the discretion of the treating physician for women of childbearing potential as per standard of care)
Timeline
Screening 3 weeks
Treatment Varies
Follow Up for the duration of the study: 3 months
Awards & highlights
Drug Has Already Been Approved
No Placebo-Only Group
Pivotal Trial

Summary

This trial will compare the safety of apixaban and rivaroxaban, two drugs used to treat venous thromboembolism (VTE).

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Who is the study for?
Adults over 18 with a new diagnosis of acute venous thromboembolism (VTE), including deep vein thrombosis or pulmonary embolism, can join this trial. They must not have had more than 72 hours of anticoagulation treatment and should have adequate kidney function. People with active bleeding, certain liver diseases, heavy body weight, or those on conflicting medications cannot participate.Check my eligibility
What is being tested?
This study compares the safety of two blood thinners—Rivaroxaban and Apixaban—in treating VTE. It's a head-to-head test to see which causes fewer bleeding problems in patients. The trial is multi-center and designed so that neither the participants nor the outcome assessors know who receives which drug.See study design
What are the potential side effects?
Both Rivaroxaban and Apixaban may increase the risk of bleeding events such as nosebleeds, heavier menstrual flow, bruising easily, prolonged bleeding from cuts, increased risk of internal bleeds like stomach or brain hemorrhages.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
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I am 18 years old or older.
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I have a new diagnosis of a serious blood clot in my leg or lungs.
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Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
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I have been on blood thinners for more than 72 hours.
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I cannot take certain blood thinners due to conditions like bleeding, cancer, being over 120kg, liver disease, other medications, another need for blood thinners, or being pregnant/breastfeeding.
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Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~for the duration of the study: 3 months
This trial's timeline: 3 weeks for screening, Varies for treatment, and for the duration of the study: 3 months for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Hemorrhage

Awards & Highlights

Drug Has Already Been Approved
The FDA has already approved this drug, and is just seeking more data.
No Placebo-Only Group
All patients enrolled in this study will receive some form of active treatment.
Pivotal Trial
The final step before approval, pivotal trials feature drugs that have already shown basic safety & efficacy.

Trial Design

2Treatment groups
Active Control
Group I: Apixaban groupActive Control1 Intervention
10 mg orally (PO), twice a day (BID) for 1 week, then 5 mg PO BID for 3 months of treatment
Group II: Rivaroxaban groupActive Control1 Intervention
15 mg orally (PO), twice a day (BID) for 3 weeks, then 20 mg PO once a day (OD) for 3 months of treatment

Find a Location

Closest Location:London Health Sciences Center· London, Canada· 228 miles

Who is running the clinical trial?

Canadian Institutes of Health Research (CIHR)OTHER_GOV
1,409 Previous Clinical Trials
26,537,660 Total Patients Enrolled
6 Trials studying Deep Vein Thrombosis
2,920 Patients Enrolled for Deep Vein Thrombosis
Canadian Venous Thromboembolism Clinical Trials and Outcomes Research (CanVECTOR) NetworkNETWORK
11 Previous Clinical Trials
14,723 Total Patients Enrolled
Ottawa Hospital Research InstituteLead Sponsor
583 Previous Clinical Trials
3,205,033 Total Patients Enrolled
8 Trials studying Deep Vein Thrombosis
3,359 Patients Enrolled for Deep Vein Thrombosis
Lana Castellucci, MD, FRCPCPrincipal InvestigatorOttawa Hospital Research Institute
2 Previous Clinical Trials
3,090 Total Patients Enrolled

Media Library

Apixaban (Anticoagulant) Clinical Trial Eligibility Overview. Trial Name: NCT03266783 — Phase 4
Deep Vein Thrombosis Research Study Groups: Apixaban group, Rivaroxaban group
Deep Vein Thrombosis Clinical Trial 2023: Apixaban Highlights & Side Effects. Trial Name: NCT03266783 — Phase 4
Apixaban (Anticoagulant) 2023 Treatment Timeline for Medical Study. Trial Name: NCT03266783 — Phase 4
~335 spots leftby Mar 2026
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