Satralizumab treatment in patients with AQP4-IgG-seropositive neuromyelitis optica spectrum disorder after rituximab treatment: A case series

Background: The US Food and Drug Administration approved satralizumab for use in adult patients with aquaporin-4 immunoglobulin G-positive (AQP4-IgG+) neuromyelitis optica spectrum disorder (NMOSD) in 2020, but real-world data are limited. The objective of this case series is to describe the experience with satralizumab in adult patients with AQP4-IgG+ NMOSD who previously received rituximab. Methods: Case information for patients with AQP4-IgG+ NMOSD who had received satralizumab for >= 6 months was obtained from US healthcare providers from April 1, 2022, to September 30, 2023. Patient characteristics, examination findings, diagnostic tests, treatment response and adverse events were recorded. Patients who received satralizumab after discontinuing treatment with rituximab were included in this case series. Results: Twenty patients were included, and their ages ranged from 19 to 70 years. Overall, 45 % of patients selfidentified as Black/African American, 40 % as White, 10 % as Asian and 5 % as multiracial. Time since confirmed NMOSD diagnosis ranged from 4 to 17 years. Median (range) duration of rituximab treatment was 50 (12-162) months. The main reasons for switching to satralizumab were intolerance (60 %) to and inadequate disease control (25 %) with rituximab. The majority of patients (70 %) received satralizumab for >= 24 months and as monotherapy (90 %). All 20 patients were free from radiographically confirmed relapses with satralizumab. Overall, patients maintained disease control with satralizumab, and adverse events primarily included asymptomatic laboratory abnormalities. Two patients permanently discontinued satralizumab due to adverse events.