Inebilizumab, an anti-CD19, B-cell depleting monoclonal antibody for adults with aquaporin-4 antibody-seropositive (AQP4+) neuromyelitis optica spectrum disorder (NMOSD), provided similar safety and efficacy for patients with new-onset NMOSD and patients treated with prior immunotherapies, according to findings presented during the American Academy of Neurology Annual Meeting.
To examine the safety and efficacy of inebilizumab as a therapy for AQP4+ NMOSD, John W. Lindsey, MD, and colleagues conducted post-hoc analyses for patients enrolled in the N-MOmentum phase 2/3 double-blind trial following their first attack. Participants were treated with inebilizumab 300 mg via IV or placebo on days 1 and 15 and every 26 weeks thereafter. Researchers administered no immunosuppressants except for oral corticosteroids within the first 2 weeks, followed by a 1-week taper. Time to first adjudicated attack served as the primary endpoint, and disability was evaluated as a secondary endpoint with the Expanded Disability Status Scale (EDSS).
Similar Results for Patients With One Vs Two or More Attacks Prior to Study
Among 37 participants enrolled in the trial, one of 24 treated with inebilizumab (4.2%) and three of 13 treated with placebo (23.1%) experienced an adjudicated attack (HR, 0.160; 95% CI, 0.017–1.542). Conversely, among 176 participants with a history of two or more attacks prior to the study, 17 of 137 treated with inebilizumab (12.4%) and 19 of 39 treated with placebo (48.7%) experienced an adjudicated attack (HR, 0.212; 95% CI, 0.110–0.408).
For participants with one pre-study attack, Dr. Lindsey and colleagues reported EDSS worsening from baseline in three of 24 patients treated with inebilizumab (12.5%) and three of 13 patients treated with placebo (23.1%; OR, 0.503 [95% CI, 0.082–3.080]), compared with 21 of 137 patients treated with inebilizumab (15.3%) and 15 of 39 patients treated with placebo (38.5%) with two or more pre-study attacks (OR, 0.309; 95% CI, 0.138–0.691).
Dr. Lindsey and colleagues reported no significant differences in attacks or EDSS worsening between participants with one pre-study attack and those with two or more pre-study attacks. Rates of treatment-emergent adverse events were similar between patients treated with inebilizumab (79.2%) and those treated with placebo (76.9%) with one pre-study attack.
