Meningococcal infection in patients receiving eculizumab or ravulizumab for generalized myasthenia gravis or neuromyelitis optica spectrum disorder: A real-world study of US clinical practice.

Eculizumab and ravulizumab are terminal complement inhibitors that are effective treatments approved for generalized myasthenia gravis (gMG) and neuromyelitis optica spectrum disorder (NMOSD) among other indications. Treatment with terminal complement inhibitors is associated with increased risk of Neisseria meningitidis (Nm) infection. This study used post-marketing and pharmacovigilance data from the Alexion safety database to assess the cumulative exposure-adjusted Nm infection and mortality rates among US patients treated with eculizumab or ravulizumab across approved indications, with a specific focus on gMG and NMOSD. The data cutoff was October 1, 2025, for eculizumab and December 31, 2025, for ravulizumab. By 2025, across all approved indications, cumulative exposure to eculizumab and ravulizumab in the United States was 34,713 and 21,348 patient-years, respectively, and cumulative Nm infection and mortality rates remained relatively stable over time (eculizumab: 0.15 and 0.01 per 100 patient-years, respectively; ravulizumab: 0.08 and 0.01 per 100 patient-years, respectively). Cumulative Nm infection rates among eculizumab-treated patients with gMG and NMOSD were 0.05 and 0.12 per 100 patient-years, respectively. Cumulative Nm infection rates among ravulizumab-treated patients with gMG or NMOSD were 0.03 and 0.13 per 100 patient-years, respectively. No mortalities due to Nm were reported for eculizumab- or ravulizumab-treated patients with gMG or NMOSD. This real-world study demonstrates that Nm infection and associated mortality rates in the United States among patients receiving eculizumab or ravulizumab have remained stably low despite increasing patient-years of exposure to each treatment. These results suggest Nm-related risk mitigation strategies are effective in patients receiving eculizumab or ravulizumab.