Clinical outcomes of prolonged anticoagulation with rivaroxaban after unprovoked venous thromboembolism

Abstract

Essentials Clinical trials demonstrated the gain of extended anticoagulation among patients with VTE. In a real-world setting, we evaluated outcomes of extended rivaroxaban use for unprovoked VTE. Extended rivaroxaban treatment lowered the risk of recurrent VTE among unprovoked VTE patients. Extended rivaroxaban treatment was not associated with increased risk of major bleeding. Background: Randomized trial data demonstrate the gain of extended duration anticoagulation in patients with venous thromboembolic events (VTE); however, real-world data are limited. Objectives: Assess the risk of recurrent VTE and major bleeding in a real-world setting of patients who experienced unprovoked VTE and received extended treatment with rivaroxaban. Methods: US claims databases (February 2011–April 2015) were used in this retrospective study. The study population included adult patients initiated on rivaroxaban within 7 days after their first unprovoked VTE (ie, deep vein thrombosis, pulmonary embolism) and received ≥3 months continuous rivaroxaban treatment (index date: end of 3-month treatment). Patients who were treated beyond 3 months formed the continued cohort and the remainder formed the discontinued cohort (ie, discontinued at 3 months). Adjusted Kaplan-Meier rates for recurrent VTE and major bleeding events were compared between cohorts with confounders being controlled through a propensity score weighting approach. Results: Patients in the continued cohort (N = 3763) had significantly lower rates of recurrent VTE than those who discontinued (N = 1051): 0.57% vs 1.19% (P =.042), 1.07% vs 2.10% (P =.017), and 1.45% vs 2.60% (P =.023) at 3, 6, and 12 months, respectively. No significant differences in the rate of major bleeding were observed between cohorts. A sensitivity analysis among unprovoked VTE patients receiving rivaroxaban for ≥6 months showed similar results. Conclusions: Continued rivaroxaban treatment beyond an initial 3- or 6-month treatment period significantly lowered the risk of recurrent VTE without a significant increase of major bleeding, compared to treatment discontinued at 3 or 6 months.