This study aims to evaluate the efficacy and safety of inebilizumab in Chinese patients with aquaporin-4 immunoglobulin G (AQP4-IgG) positive neuromylitis optic spectrum disorders (NMOSD) in a real-world setting.

Inebilizumab, a humanized anti-CD19 B cell-depleting monoclonal antibody, has received approval for the treatment of adult NMOSD patients with AQP4-IgG-positive, following the positive results of a phase 2/3 trial (NCT02200770). However, there is a persistent need to explore the real-world management of NMOSD.

A total of 45 AQP4-IgG-seropositive NMOSD patients were enrolled, with an average age of 44.8±14.1 years. The mean follow-up duration after initiating inebilizumab treatment was 10.5±3.8 months. At 6-month follow up, no relapses were reported. The EDSS score decreased from a median of 2.75 (range 1.5 to 8.5) to 2.0 (range 1.0 to 7.5), and a more than twofold decrease in AQP4-IgG titters (p<0.01, p<0.05, respectively). The CD19+ B lymphocyte counts also significantly decreased from 418.2±306.6/μl to 5.4±12.0/μl (p<0.01). Among 153 intravenous injections, only one patient reported an allergic reaction, which resolved after discontinuation of the treatment. No severe infections were reported, although there was a slightly decrease in serum levels of IgG, IgM and IgA.

Inebilizumab significantly reduced attacks, the EDSS score and serum AQP4-IgG titter in AQP4-IgG-positive NMOSD patients, without any serious adverse reaction reported, indicating that it is an effective and safe therapeutic option for NMOSD patients in the real-world.