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Comparison of Bleeding Risk Between Rivaroxaban and Apixaban (COBRRA Pilot)

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ClinicalTrials.gov Identifier: NCT02559856
Recruitment Status : Completed
First Posted : September 24, 2015
Last Update Posted : April 17, 2018
Sponsor:
Collaborator:
Canadian Institutes of Health Research (CIHR)
Information provided by (Responsible Party):
Ottawa Hospital Research Institute

Brief Summary:
This vanguard pilot study compares rivaroxaban and apixaban, two of the new oral blood thinners for the treatment of blood clots. Half of the patients will receive apixaban and half will receive rivaroxaban. The main objective is to determine the feasibility of patient recruitment and resources required to follow enrolled patients and inform for a larger, multi-centered trial and to assess which one is safer.

Condition or disease Intervention/treatment Phase
Venous Thromboembolism Drug: Apixaban Drug: Rivaroxaban Phase 4

Detailed Description:
Recently developed new oral anticoagulants (OAC) overcome some of the limitations of established therapy with vitamin K antagonists (VKA) and low molecular weight heparin (LMWH) for treatment of acute venous thromboembolism (VTE), due to ease of administration and more predictable pharmacokinetic properties. Many clinical questions about the new OAC remain unanswered because there have not been direct head-to-head comparison trials. For example, although studies have shown that rivaroxaban and apixaban are at least as effective and safe as LMWH and VKA, meta-analyses suggest that apixaban may be associated with lower bleeding risk. Concerns about the potential impact of medication non-adherence have been raised. Compliance with twice daily medications (e.g. apixaban) is often worse than once daily medications (e.g. rivaroxaban). Both of these medications are approved by Health Canada for treatment of VTE yet there is genuine uncertainty about which of the two direct OAC confer the best risk-to-benefit ratio.This is a multi-centre, prospective randomized open blinded end-point (PROBE) trial assessing clinical feasibility for a larger multi-centered trial comparing bleeding outcomes using apixaban vs. rivaroxaban for treatment of acute VTE. The primary objective of the study is to determine if it is feasible to conduct a large randomized multicenter trial comparing apixaban vs. rivaroxaban for the treatment of acute VTE. The secondary objectives are to assess safety and superiority of apixaban vs rivaroxaban.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 72 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Comparison of Bleeding Risk Between Rivaroxaban and Apixaban for the Treatment of Acute Venous Thromboembolism: The Pilot Study
Actual Study Start Date : May 2016
Actual Primary Completion Date : November 2017
Actual Study Completion Date : February 2018

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Active Comparator: Apixaban
10 mg PO twice-a-day for 1 week, then 5 mg PO, twice daily for 3 or 6 months of treatment.
Drug: Apixaban
Other Name: Eliquis

Active Comparator: Rivaroxaban
15 mg PO twice-a-day for 3 weeks, then 20 mg PO once daily for 3 or 6 months of treatment.
Drug: Rivaroxaban
Other Name: Xarelto




Primary Outcome Measures :
  1. Proportion of patients screened who are eligible to participate in the trial [ Time Frame: For the duration of the study 3-6 months ]
  2. Proportion of eligible patients who consent to participate in the trial [ Time Frame: For the duration of the study 3-6 months ]
  3. Proportion of patients who attend each follow-up visit [ Time Frame: For the duration of the study 3-6 months ]
  4. Proportion of patients completing all required study procedures, per follow-up visit [ Time Frame: For the duration of the study 3-6 months ]

Secondary Outcome Measures :
  1. Bleeding Events [ Time Frame: For the duration of the study 3-6 months ]
    Major bleeding events, clinically relevant non-major and minor bleeding episodes

  2. Venous Thromboembolism [ Time Frame: For the duration of the study 3-6 months ]
    Recurrent VTE and VTE related-death

  3. Death [ Time Frame: For the duration of the study 3-6 months ]
    • All-cause mortality rates
    • Individual rates of death related to VTE, cardiovascular disease, bleeding or other causes

  4. Medication compliance as assessed by study pill count [ Time Frame: For the duration of the study 3-6 months ]
  5. Time-to-event analysis [ Time Frame: For the duration of the study 3-6 months ]
    The time-to-first occurrence of secondary outcomes between randomization and end of follow-up



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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Confirmed newly diagnosed acute VTE (proximal lower extremity DVT and segmental or greater PE)
  • Age ≥ 18 years old
  • Written informed consent

Exclusion Criteria:

  • Any contraindication for anticoagulation such as active bleeding
  • Clinically significant liver disease or alanine aminotransferase (ALT) levels ≥ 3 times the upper limit of normal range
  • Creatinine clearance < 30 ml/min calculated with the Cockcroft-Gault formula (29)
  • Known allergies to either apixaban or rivaroxaban
  • Pregnancy
  • Use of contraindicated medications with apixaban or rivaroxaban
  • Active malignancy in the last 6 months (excluding localized skin malignancy)
  • No private insurance coverage for the study drug or not willing to pay for study drug

Information from the National Library of Medicine

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): NCT02559856


Locations
Canada, Ontario
The Ottawa Hospital - General Campus
Ottawa, Ontario, Canada, K1H 8L6
Sponsors and Collaborators
Ottawa Hospital Research Institute
Canadian Institutes of Health Research (CIHR)
Investigators
Principal Investigator: Lana Castellucci, MD Ottawa Hospital Research Institute

Responsible Party: Ottawa Hospital Research Institute
ClinicalTrials.gov Identifier: NCT02559856     History of Changes
Other Study ID Numbers: COBRRA Pilot
20150574-01H ( Other Identifier: OHSN REB )
First Posted: September 24, 2015    Key Record Dates
Last Update Posted: April 17, 2018
Last Verified: April 2018

Additional relevant MeSH terms:
Thromboembolism
Venous Thromboembolism
Embolism and Thrombosis
Vascular Diseases
Cardiovascular Diseases
Rivaroxaban
Apixaban
Factor Xa Inhibitors
Antithrombins
Serine Proteinase Inhibitors
Protease Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anticoagulants