The EXPAND study: Efficacy and safety of rivaroxaban in Japanese patients with non-valvular atrial fibrillation

Aims: The EXPAND study examined the real-world efficacy and safety of rivaroxaban for the prevention of stroke and systemic embolism (SE) in Japanese patients with non-valvular atrial fibrillation (NVAF). Methods and results: This multicenter, prospective, non-interventional, observational, cohort study was conducted at 684 medical centers in Japan. A total of 7141 NVAF patients ≥20 years of age (mean, 71.6 ± 9.4 years) who were being or about to be treated with rivaroxaban (10 mg/day, 43.5%; 15 mg/day, 56.5%) were followed for an average of 897.1 (±206.8) days with a high follow-up rate (99.65%). The mean CHADS₂ score at baseline was 2.1 (1.3) (0–1, 37%; 2, 29%; ≥3, 34%). The total incidence rate of symptomatic stroke and SE (primary efficacy endpoint) was 1.0%/year, and 0.5%, 0.9%, and 1.7%/year for those with CHADS₂ scores of 0–1, 2, and ≥3, respectively. Cumulative incidence rates for major bleeding (primary safety endpoint) and non-major bleeding (secondary safety endpoint) were 1.2%/year and 4.9%/year, respectively. Differences were noted between new and current users only for major bleeding event rate (1.7% vs. 1.1%/year, P = 0.0024). Comparisons with previous studies suggested that rivaroxaban is effective and safe for low-risk patients (0–1 CHADS₂), as shown for warfarin in the XANTUS international prospective post-marketing study. Conclusions: The EXPAND study demonstrated that low dosages of rivaroxaban for Japanese NVAF patients in real-world clinical practice, including those with CHADS₂ scores 0–1, resulted in low rates of stroke and SE, and major and non-major bleeding.