Effectiveness and safety of rivaroxaban versus warfarin in patients with provoked venous thromboembolism.

A paucity of real-world data evaluating rivaroxaban in provoked venous thromboembolism (VTE) exists. We assessed the effectiveness and safety of rivaroxaban versus warfarin in provoked VTE patients treated in routine practice. Using MarketScan claims data from 1/2012 to 12/2016, we identified adults who had ≥ 1 primary hospitalization/emergency department discharge diagnosis code for VTE (index event) and a provoking factor, received rivaroxaban or warfarin as their first outpatient oral anticoagulant within 30-days of the index event and had ≥ 12-month of insurance coverage prior the index VTE. Provoking factors included cancer, hospital admission for ≥ 3-consecutive days over the prior 3-months, major surgery, trauma or fracture within 90-days or pregnancy within 42-weeks of the index VTE. Differences in baseline covariates between cohorts were adjusted using inverse probability-of-treatment weights based on propensity-scores (residual standardized differences < 0.1 achieved for all covariates after adjustment). The incidence of the composite endpoint of recurrent VTE or major bleeding at 3- and 6-months was compared using Cox regression and reported as hazard ratios (HRs) and 95% confidence intervals (CIs). We included 4454 rivaroxaban and 13,164 warfarin users with provoked VTE. At 3- and 6-months, rivaroxaban was associated with a reduced hazard of the composite endpoint (HR 0.72, 95% CI 0.61-0.84 and HR 0.69, 95% CI 0.60-0.80) and recurrent VTE (HR 0.70, 95% CI 0.59-0.84 and HR 0.71, 95% CI 0.60-0.84) versus warfarin. Major bleeding was non-significantly reduced at 3-months (HR 0.77, 95% CI 0.57-1.06) and significantly reduced at 6-months (HR 0.68, 95% CI 0.53-0.88) with rivaroxaban. Rivaroxaban reduces recurrent VTE and major bleeding risk versus warfarin in provoked VTE patients treated in routine practice.