Efficacy and Safety of Monoclonal Antibody Therapy in Neuromyelitis Optica Spectrum Disorders: Evidence from Randomized Controlled Trials

Background : Neuromyelitis optica spectrum disorders (NMOSD) are autoimmune inflammatory disorders in central nervous system (CNS) characterized by symptoms of optic nerve, spinal cord, brainstem and cerebrum injuries. Recent studies have shown that monoclonal antibodies (Rituximab, Eculizumab, Inebilizumab, Satralizumab, etc.) were effective for the treatment of NMOSD. We performed a meta-analysis to evaluate the efficacy and safety of these monoclonal antibodies in NMOSD. Methods : The MEDLINE, EMBASE, Central Register of Controlled Trials (CENTRAL) and clinicaltrials.gov database were searched for randomized controlled trials (RCTs) which had assessed the therapy of monoclonal antibody in NMOSD patients. Results : We pooled 524 (monoclonal antibody group, n = 344 and placebo group, n = 180) from 4 RCTs and 444 patients (84.7%) were AQP4-IgG seropositive. Monoclonal antibody therapy reduced annualized relapse rate (mean -0.27, 95% CI, -0.36 to -0.18, P <0.0001), on-trial relapse risk (RR 0.25, 95% CI 0.12 to 0.52, P = 0.0003), EDSS (Expanded disability status scale) score (mean -0.51, 95% CI, -0.92 to -0.11, P = 0.01) and serious adverse events (RR 0.59, 95% CI 0.37 to 0.96, P = 0.03) but didn't show any significant differences in total adverse events or mortality. In the subgroup analysis, we found that comparing with other monoclonal antibodies, Eculizumab might be more effective in decreasing on-trial relapse risk (Chi2 =9.84, P =0.002) for AQP-4 positive patients. Conclusions : Monoclonal antibody therapy was effective and safe in NMOSD treatment. More RCTs were expected to assess monoclonal antibodies in NMOSD.