Long-term effectiveness and safety of satralizumab for neuromyelitis optica spectrum disorder in a real-world clinical setting in Japan: A 2.5-year final analysis of a multicenter medical chart review (The SAkuraBeyond Study)

Purpose: To evaluate the real-world effectiveness and safety of satralizumab over 2.5 years using medical data charts of satralizumab-treated Japanese patients with aquaporin-4 immunoglobulin-G seropositive neuromyelitis optica spectrum disorder (AQP4[+] NMOSD). Major findings: Overall, 124 patients were evaluated (mean ± standard deviation: age, 51.1 ± 14.0 years; disease duration, 7.0 [6.0] years). At baseline, 72.6%, 16.9%, and 35.5% of patients received oral glucocorticoids (GCs), azathioprine (AZA), and tacrolimus (TAC), respectively. The annualized relapse rate (ARR [95% confidence interval]) decreased from 0.45 (0.34–0.58) within 52 weeks before satralizumab initiation to 0.03 (0.02–0.07) after 130 weeks of satralizumab initiation; relapse-free rate was 91.8% at 130 weeks. Nine patients had nine relapses; seven were re-administered satralizumab after relapse. At 130 weeks, 48.8% of relapse-free patients were not receiving oral GCs (89.3% received ⩽5 mg/day); mean oral GC dose reduced from 10.3 to 2.5 mg/day. In patients receiving AZA and TAC at baseline, 80.0% and 47.1% were no longer receiving AZA and TAC at 130 weeks, respectively. Serious drug reactions occurred in 9.7% of patients (serious infections, 6.5%). Conclusion: The real-world relapse-free rate at 2.5 years was 91.8% (ARR = 0.03) in satralizumab-treated patients with AQP4[+] NMOSD, supporting the relapse-preventive effect of satralizumab without new safety concerns. Registration number: UMIN000050027