Real-world effectiveness and safety of rivaroxaban versus warfarin among non-valvular atrial fibrillation patients with obesity in a US population

Objectives Current evidence indicates that the pharmacokinetic profile of rivaroxaban is not significantly impacted by body weight. However, real-world data are needed to better assess the potential clinical benefits and risks associated with rivaroxaban in non-valvular atrial fibrillation (NVAF) patients with obesity. Thus, our objectives were to assess the real-world effectiveness and safety of rivaroxaban versus warfarin among NVAF patients with obesity in the US nationally representative commercially-insured population. Methods Health insurance claims data from the IQVIA PharMetrics Plus database (January 2010-September 2019) were used to identify NVAF patients with obesity (based on diagnosis codes) initiated on rivaroxaban or warfarin. Inverse probability of treatment weighting (IPTW) was used to adjust for imbalances between groups. Study outcomes of interest were evaluated up to 36 months post-treatment initiation and included the composite of stroke or systemic embolism (stroke/SE) and major bleeding. Outcomes were compared using Cox proportional hazards regression models with hazard ratios (HR) and 95% confidence intervals (CIs). Results A total of 10,555 patients were initiated on rivaroxaban and 5080 patients on warfarin. Following IPTW, the risk of stroke/SE was 26% lower among patients prescribed rivaroxaban relative to warfarin (HR: 0.74, 95% CI: 0.60, 0.91, p = .004) at 36 months. Rivaroxaban-initiated patients had a risk of major bleeding similar to that of warfarin-initiated patients (HR: 0.85, 95% CI: 0.71, 1.02, p = .085). Conclusions These results suggest that rivaroxaban is an effective and safe treatment option among NVAF patients with obesity in a commercially-insured US population.

Automated summary

This study demonstrated that rivaroxaban is an effective and safe treatment option for NVAF patients with obesity in a commercially-insured US population, with a 26% lower risk of stroke/SE compared to warfarin at 36 months post-treatment initiation. The risk of major bleeding was similar between rivaroxaban-initiated patients and warfarin-initiated patients.