Rivaroxaban for Scheduled Work-up of DVT - The Ri-Schedule Study

Study Overview
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Brief Summary
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This prospective outcome study is designed to assess the safety of rivaroxaban in the pre-diagnosis phase of DVT.

Detailed Description
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This prospective outcome study is designed to assess the safety of rivaroxaban in the pre-diagnosis phase of DVT. International guidelines suggest the use of low molecular weight heparin (LMWH) if the diagnostic process is expected to be delayed for more than 4 hours. Rivaroxaban is a new DOAC that in clinical trials has proven to be non-inferior to LMWH and warfarin for the treatment of DVT with the added benefit of causing less major bleeding. Because of its rapid onset of action and oral administration, rivaroxaban could be used instead of LMWH in the pre-diagnosis phase pending the results of the diagnostic test. However, the safety of a such proposed indication has to be proven before it can be adopted in clinical practice. This study aims to determine the safety and feasibility of pre-diagnostic treatment with rivaroxaban. The primary outcome of this study safety is a composite endpoint of serious bleedings encountered within 48 hours after administration of rivaroxaban.

Official Title
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Rivaroxaban for Scheduled Work-up of Patients With Suspected Deep Venous Thrombosis

Conditions
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Deep Venous Thrombosis

Intervention / Treatment
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* Drug: Rivaroxaban


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Consecutive outpatients referred to ER because of suspected DVT 18 years of age Signed informed consent Exclusion Criteria: 1- refuse to consent Patients with the criteria below will not be eligible for scheduled work-up: Duration of the diagnostic work-up is expected to last < 2 hours Presence of active cancer or receiving chemotherapy for cancer Suspicion of coexisting clinical PE Suspicion of active bleeding (gastrointestinal bleeding or muscle hematoma) Signs of threatened circulation or having intractable pain in the lower extremity or may be considered as candidate for thrombolytic treatment Physician does not consider it safe to discharge the patient Presence of logistic factors that may hinder a scheduled work-up Presence of co-morbid conditions that require hospital admission Patient prefers not to be discharged before diagnosis is completed Glomerular Filtration Rate < 45 ml/min Presence of contraindications to rivaroxaban including; Lesion or condition, if considered to be a significant risk for major bleeding e.g current or recent gastrointestinal ulceration, presence of malignant neoplasms at high risk of bleeding, recent brain or spinal injury, recent brain, spinal or ophthalmic surgery, recent intracranial haemorrhage, known or suspected oesophageal varices, arteriovenous malformations, vascular aneurysms or major intraspinal or intracerebral vascular abnormalities Concomitant treatment with any other anticoagulants e.g. unfractionated heparin (UFH), low molecular weight heparins (enoxaparin, dalteparin, etc.), heparin derivatives (fondaparinux, etc.), oral anticoagulants (warfarin, dabigatran etexilate, apixaban etc.) Hepatic disease associated with coagulopathy and clinically relevant bleeding risk including cirrhotic patients with Child Pugh B and C. Pregnancy/positive pregnancy test and breastfeeding (see section 4.6) 11. Hb < 11 g/dl 12. Presence of drug interaction with rivaroxaban including concomitant systemic treatment with azole-antimycotics (such as ketoconazole, itraconazole, voriconazole and posaconazole) or HIV protease inhibitors (e.g. ritonavir), acetylsalicylic acid at a dose higher than 160 mg or platelet aggregation inhibitors

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 95 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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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Rivaroxaban<br>Rivaroxaban 15 mg every 12 hours until the completion of the diagnostic work-up, which should not exceed 24 hours. | Drug: Rivaroxaban<br>* Rivaroxaban 15 mg every 12 hours until the completion of the diagnostic work-up, which should not exceed 24 hours (maximum 2 tablets)<br>* Other names: Xarelto;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of serious bleedings and/or death related to bleeding | Serious bleedings and/or death related to bleeding encountered within 48 hours after the last rivaroxaban tablet was ingested in patients in whom DVT was excluded or until the ingestion of first tablet of oral anticoagulation or application of IV/SC heparin in those in whom DVT is confirmed. | Until 48 hours after last tablet | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Feasability rate | Assessed by the proportion of patients who can be managed by a scheduled work-up | 12 hours | 
| Failure rate | Worsening in pre-existing complaints or developement of signs/symptoms of pulmonary embolism | until 48 hours after last tablet | 
| 90-day outcome | The 90-day outcome of the applied diagnostic strategy using Wells pre-test clinical probability, D-dimer and compression ultrasounography and safety of coagulation | 90 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Deep venous thrombosis, Rivaroxaban