Prevention of Recurrence After Thrombolysis in Acute Iliofemoral Venous Thrombosis with Rivaroxaban (Prais Study): A Prospective, Randomized, Open Label, Multicenter Trial

Abstract

Introduction: Recently new oral anticoagulants (NOAC) has replaced vitamin K antagonist (VKA) for the treatment of deep vein thrombosis (DVT). But the role of NOAC after thrombolysis of acute iliofemoral DVT is not yet defined. The aim of this randomized clinical trial is to compare the safety and efficacy of rivaroxaban versus VKA after thrombolysis of acute iliofemoral DVT. Methods: Patients were recruited from 7 hospitals in Korea. After successful thrombolysis or mechanical thrombectomy of acute iliofemoral DVT, 72 patients were randomized to standard anticoagulation (enoxaparin and warfarin) or rivaroxaban. Primary efficacy outcome was recurrence of any venous thromboembolism within 6 months. Secondary safety outcome were major bleeding and clinically relevant non-major bleeding (CRNMB). Other safety variables including any adverse events, vascular events, and all-cause mortality were also analyzed. Results: Intention-to-treat analysis was done for 67 patients (35 in rivaroxaban group, and 32 in VKA group). The primary outcome of recurrent VTE occurred in 4 patients in each group (11.4% vs 12.5%; hazard ratio[HR], 0.90; 95% confidence interval [CI], 0.21 to 3.96; P=1). Major bleeding or CRNMB developed in 1 patient in the rivaroxaban group and 3 patients in the VKA group (2.9% vs 9.4%, HR, 0.28; 95% CI, 0.03 to 2.88; P=0.34). Recurrence-free survival and significant bleeding-free survival at 6 month were not different in both groups. (P=0.28 and P=0.98, respectively) Conclusion: After thrombolysis of acute iliofemoral DVT, rivaroxaban was as effective as warfarin for the prevention of DVT recurrence. Rivaroxaban group showed a tendency of lower incidence of major bleeding/CRNMB. Rivaroxaban can safely replace warfarin in patients after successful thrombolysis for acute iliofemoral DVT. (Funded by Bayer Schering Pharma; ClinicalTrials.gov number, NCT01986192.)