OBJECTIVES : Neuromyelitis Optica (NMO, also known as Devic’s disease) is a rare, debilitating autoimmune disorder of the central nervous system, dominated by inflammation of the optic nerve (optic neuritis) and spinal cord (myelitis). Several immunosuppressants and monoclonal antibodies such as corticosteroids, azathioprine, and rituximab have been prescribed widely as preventive treatment for NMO. However, there is a dearth of evidence on the optimal use of these therapies. The objective of this study, therefore, is to compare and rank the efficacy and safety of all preventive therapies for NMO by conducting systematic literature review (SLR) and network meta-analysis (NMA) of relevant studies.

METHODS : Qualified studies were identified in a search of MEDLINE, Embase, CENTRAL, and ClinicalTrials.gov databases, from 2019 to the inception of databases. Studies assessing freedom from relapse, reduction of disability and the occurrence of adverse events were considered. Outcomes were analyzed using a Bayesian NMA adopting a fixed-effect model. Mean differences in change from baseline and mean odds ratios (OR) with 95% credible intervals (CrIs) were calculated.

RESULTS : The SLR identified 18 relevant studies that were subject to feasibility assessment, of which 10 studies (two RCTs, six retrospective and two prospective observational studies) were included in the NMA. Tocilizumab (OR: 4.48; 95%CrI: 1.73, 13.34) and tacrolimus (OR: 2.85; 95% CrI: 0.93, 9.54) demonstrated greater relapse-free rate in comparison to azathioprine in NMO patients. For disability, measured by change in expanded disability status scale score, rituximab was hierarchically superior with significant mean difference versus azathioprine (0.63; 95% CrI: 0.31, 0.96). As compared to azathioprine, rituximab had a favorable safety profile, followed by tocilizumab and tacrolimus.

CONCLUSIONS : Tocilizumab and tacrolimus may be considered as optimal treatments to prevent relapse in NMO. Rituximab improves disability in patients and is associated with relatively lesser adverse events compared to other preventive therapies.