Effectiveness of satralizumab in a real-world clinical setting in Japan: Interleukin-6 receptor inhibition in neuromyelitis optica spectrum disorder: A six-month interim analysis of a multicenter medical chart review

Background

Satralizumab is approved in Japan for relapse prevention of neuromyelitis optica spectrum disorder (NMOSD) in aquaporin-4 immunoglobulin G–seropositive (AQP4[+]) patients. However, clinical trial data for Japanese patients are limited.

Methods

SAkuraBeyond, an ongoing real-world observational study (UMIN000050027), evaluates NMOSD relapse over 2.5 years among satralizumab-treated patients with AQP4[+] NMOSD in Japan (25 sites). Herein, we present a 26-week interim effectiveness analysis. Patient data were derived from medical chart review and electronic case report forms.

Results

Of the 125 enrolled patients who initiated satralizumab, 124 were included in the study (mean age, 51.1 years; female, 93.5 %; mean disease duration, 7.0 years). At week 26, 120 patients were relapse-free (12 withdrew from satralizumab). The annualized relapse rate [95 % confidence interval (CI)] was 0.069 [0.026–0.183] at week 26 after satralizumab initiation and 0.445 [0.342–0.580] within 52 weeks before satralizumab initiation. The relapse-free rate [95 % CI] at week 26 was 96.6 % [91.2–98.7]. Four patients had relapses, of whom 1 discontinued satralizumab. Three recorded a modified Rankin Scale of ≤3 (1 with unknown status). The mean oral glucocorticoid (GC) dose reduced from baseline to 26 weeks of satralizumab treatment; the GC dose was reduced in 71.3 % of patients treated with oral GC >0 mg at baseline. Azathioprine and tacrolimus doses could be reduced to 0 mg/day in 35.3 % and 26.2 % of relapse-free patients, respectively, at week 26.

Conclusion

The 6-month relapse-free rate after satralizumab treatment was 96.6 %. Satralizumab use permitted dose reduction of concomitant oral GC and immunosuppressants over 26-weeks.