Real‐World Investigation of Satralizumab in Patients With Neuromyelitis Optica Spectrum Disease

Objective Satralizumab, a monoclonal antibody targeting the interleukin‐6 receptor, has demonstrated efficacy in clinical trials for neuromyelitis optica spectrum disorder (NMOSD). However, its real‐world effectiveness and safety compared to conventional immunosuppressive therapies remain uncertain. Methods We identified patients diagnosed with NMOSD in the TriNetX federated health research platform between January 2018 and April 2024. This international platform was accessed via Taipei Medical University. Patients were followed for 1 month to 3 years. A 1:1 propensity‐score matching (PSM) analysis balanced baseline characteristics between the satralizumab and conventional immunosuppressant groups. Risk ratios (RRs) were calculated for relapse risk and safety outcomes, including sepsis, respiratory infection, urinary tract infection, anemia, neutropenia, and mortality. Results A total of 220 patients received satralizumab, while 1744 received conventional immunosuppressants. After PSM, 218 patients remained in each group. Satralizumab was associated with a significantly lower relapse risk at 1 month (RR: 0.38, 95% CI 0.21–0.66), 3 months (RR: 0.43, 95% CI 0.28–0.66), 6 months (RR: 0.50, 95% CI 0.33–0.70), 9 months (RR: 0.62, 95% CI 0.46–0.83), 12 months (RR: 0.63, 95% CI 0.47–0.83), 24 months (RR: 0.60, 95% CI 0.42–0.86) and 36 months (RR: 0.52, 95% CI 0.32–0.83). Across all follow‐up intervals, numbers needed to treat were consistently between 4 and 9. No significant differences were observed in infection rates, anemia, neutropenia, or mortality between the groups. Interpretation Satralizumab demonstrated superior efficacy in reducing NMOSD relapse rates compared to conventional immunosuppressants while maintaining a comparable safety profile.