Assays for and Reversal of New Anticoagulants

Study Overview
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Brief Summary
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New anticoagulants are being introduced to replace warfarin. These drugs do not require monitoring and are safer. There is currently no recommended way to reverse these drugs rapidly in the event of undue bleeding or need for emergency surgery. This is a lab study to look at ways to reverse the drugs rapidly

Detailed Description
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We are developing in vitro assays of measurement of the effect of these drugs on the relevant coagulation pathways in plasma; such assays are not widely established. This will then allow us to test potential reversing agents such as activated Factor VII (Novo-Seven®), or Factor VIII inhibitor bypassing agent (FEIBA) for their ability to reverse these anti-coagulants invitro. The aims of this reversal research strategy is to provide a means whereby patients who present with serious bleeding or who need rapid reversal for surgery, for example, can be offered such treatment to allow rapid normalisation of their coagulation system. As part of this developmental programme, we wish to obtain samples from patients receiving Rivaroxaban or Dabigatran for therapeutic reasons, to test the effect of the respective drug on the relevant coagulation factors and to test in vitro reversibility. The only requirement for the patient is to have an extra 20ml of blood taken at a time when the patient is having other blood tests. There are no risks or experimental procedures planned to be carried out on patients.

Official Title
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Development of Anticoagulant Assays for New Anticoagulants and Their Reversibility in Vitro

Conditions
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Atrial Fibrillation, Osteoarthritis of the Knee, Osteoarthritis of the Hip

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Receiving dabigatran for atrial fibrillation Or,for osteoarthritis of the hip or knee receiving rivaroxaban to prevent thromboembolic disease after total hip or knee replacement respectively Exclusion Criteria: Failure to sign informed consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients receiving a new anticoagulant<br>Patients are receiving dabigatran for atrial fibrillation or rivaroxaban for osteoarthritis of hip or knee undergoing total hip or knee replacement respectively | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ability to reverse anticoagulant effect in vitro of dabigatran or rivarovaban | The ability of nonspecific coagulation factors to reverse anticoagulant effect in vitro as measured by dilute thrombin time, Calibrated automated thrombinoscope, thromboelastogram and Rotem | Two hours after ingestion of anticoagulant dose | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anticoagulant measurement, Anticoagulant reversal, Dabigatran, Rivaroxaban