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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/show/NCT03266783




Registration number
NCT03266783
Ethics application status
Date submitted
1/11/2019
Date registered
28/08/2017
Date last updated
4/11/2019

Titles & IDs
Public title
Comparison of Bleeding Risk Between Rivaroxaban and Apixaban for the Treatment of Acute Venous Thromboembolism
Scientific title
Comparison of Bleeding Risk Between Rivaroxaban and Apixaban for the Treatment of Acute Venous Thromboembolism
Secondary ID [1] 0 0
COBRRA
Universal Trial Number (UTN)
Trial acronym
COBRRA
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Venous Thromboembolism 0 0
Condition category
Condition code
Cardiovascular 0 0 0 0
Diseases of the vasculature and circulation including the lymphatic system
Blood 0 0 0 0
Clotting disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Treatment: Drugs - Apixaban
Treatment: Drugs - Rivaroxaban

Active Comparator: Apixaban group - 10 mg PO BID for 1 week, then 5 mg PO BID for 3 months of treatment

Active Comparator: Rivaroxaban group - 15 mg PO BID for 3 weeks, then 20 mg PO OD for 3 months of treatment


Treatment: Drugs: Apixaban
Refer to Apixaban group

Treatment: Drugs: Rivaroxaban
Refer to Rivaroxaban group

Intervention code [1] 0 0
Treatment: Drugs
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
The rate of adjudicated clinically relevant bleeding (CRB) events - CRB events are defined as the composite of major bleeding (MB) events and clinically relevant non-major bleeding (CRNMB) events.
Timepoint [1] 0 0
For the duration of the study: 3 months
Secondary outcome [1] 0 0
Adjudicated Major Bleeding events
Timepoint [1] 0 0
For the duration of the study: 3 months
Secondary outcome [2] 0 0
Adjudicated Clinically Relevant Non-Major Bleeding events
Timepoint [2] 0 0
For the duration of the study: 3 months
Secondary outcome [3] 0 0
Adjudicated recurrent VTE events
Timepoint [3] 0 0
For the duration of the study: 3 months
Secondary outcome [4] 0 0
Adjudicated VTE-related deaths
Timepoint [4] 0 0
For the duration of the study: 3 months
Secondary outcome [5] 0 0
All-cause mortality
Timepoint [5] 0 0
For the duration of the study: 3 months
Secondary outcome [6] 0 0
Medication adherence
Timepoint [6] 0 0
For the duration of the study: 3 months
Secondary outcome [7] 0 0
Quality-adjusted life years (QALYs) gained
Timepoint [7] 0 0
For the duration of the study: 3 months
Secondary outcome [8] 0 0
Incremental cost-effectiveness ratio
Timepoint [8] 0 0
For the duration of the study: 3 months
Secondary outcome [9] 0 0
Impact of verbal consent on patient participation in comparison with participants from sites using written informed consent
Timepoint [9] 0 0
For the duration of the study: 3 months

Eligibility
Key inclusion criteria
- Confirmed newly diagnosed symptomatic acute VTE (proximal power extremity DVT or
segmental or greater PE)

- Age ≥ 18 years old

- Informed consent obtained
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
- Have received > 72 hours of therapeutic anticoagulation

- Creatinine clearance < 30 ml/min calculated with the Cockcroft-Gault formula

- Any contraindication for anticoagulation with apixaban or rivaroxaban as determined by
the treating physician such as, but not limited to:

- active bleeding,

- active malignancy, defined as a) diagnosed with cancer within the past 6 months;
or b) recurrent, regionally advanced or metastatic disease; or c) currently
receiving treatment or have received any treatment for cancer during the 6 months
prior to randomization; or d) a hematologic malignancy not in complete remission,

- 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)

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
Recruitment outside Australia
Country [1] 0 0
Canada
State/province [1] 0 0
Alberta
Country [2] 0 0
Canada
State/province [2] 0 0
British Columbia
Country [3] 0 0
Canada
State/province [3] 0 0
Nova Scotia
Country [4] 0 0
Canada
State/province [4] 0 0
Ontario
Country [5] 0 0
Canada
State/province [5] 0 0
Quebec

Funding & Sponsors
Primary sponsor type
Other
Name
Ottawa Hospital Research Institute
Address
Country
Other collaborator category [1] 0 0
Other
Name [1] 0 0
Canadian Institutes of Health Research (CIHR)
Address [1] 0 0
Country [1] 0 0
Other collaborator category [2] 0 0
Other
Name [2] 0 0
Canadian Venous Thromboembolism Clinical Trials and Outcomes Research (CanVECTOR) Network
Address [2] 0 0
Country [2] 0 0

Ethics approval
Ethics application status

Summary
Brief summary
Apixaban and rivaroxaban have been compared to standard therapy for treatment of acute
symptomatic venous thromboembolism (VTE) in randomized controlled trials (RCTs), and are both
approved by Health Canada. No safety or efficacy data is available from direct head-to-head
comparison of these two anticoagulants. Lawsuits in the United States over bleeding events,
patient perceptions, and concerns with medication adherence are additional factors
highlighting the importance of a comparison trial. This multi-center, pragmatic, prospective,
randomized, open-label, blinded end-point (PROBE) trial aims to compare the safety of
apixaban and rivaroxaban for the treatment of VTE.
Trial website
https://clinicaltrials.gov/show/NCT03266783
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Lana Castellucci, MD, FRCPC
Address 0 0
Ottawa Hospital Research Institute
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Lana Castellucci, MD, FRCPC
Address 0 0
Country 0 0
Phone 0 0
613-737-8899
Fax 0 0
Email 0 0
lcastellucci@toh.ca
Contact person for scientific queries

Summary results
For IPD and results data, please see https://clinicaltrials.gov/show/NCT03266783