Rituximab for the Treatment of Neuromyelitis Optica Spectrum Disorder

Key Message

Four systematic reviews, 1 randomized controlled trial (RCT), 1 economic evaluation, and 2 evidence-based guidelines were identified.Four systematic reviews (2 that included moderate- to high-quality evidence and 2 that did not report the quality of the evidence) and 1 RCT (that provided high-quality evidence) reported on the clinical effectiveness of rituximab (RTX) for the treatment of neuromyelitis optica spectrum disorder (NMOSD). Overall, RTX treatment appeared to reduce the relapse rate and disability level compared with pre-treatment or placebo. In terms of reduction in relapse rate and disability, RTX was either better or not different from azathioprine (AZA). For relapse rates, disability levels, and incidence of adverse events, network meta-analyses showed that no treatment was favoured for comparisons between RTX, mycophenolate mofetil (MMF), and cyclophosphamide (CYP).One economic evaluation (of moderate quality) showed that, for patients with NMOSD, in the context of the Thai health care system, RTX biosimilar with CD27+ memory B cell monitoring regimen had the highest probability (48%) of being cost-effective, followed by AZA (30%), MMF (13%), RTX with CD27+ memory B cell monitoring regimen (9%), RTX biosimilar (0%), and RTX (0%) at a willingness-to-pay threshold of 160,000 Thai bhat (equivalent to US$5,289 in 2019 values) per quality-adjusted life-year gained.The 2 guidelines recommended immunosuppressants (RTX, AZA, and MMF) for prevention of NMOSD attacks. In addition, 1 guideline mentioned that tocilizumab, eculizumab, inebilizumab, and satralizumab can be used in NMOSD leave it up to patients who have no response to other immunosuppressants. The quality of the evidence that informed the guidelines and the strength of the recommendations were not reported.Findings need to be interpreted with caution given the limited quantity of evidence on comparative efficacy and safety between various immunosuppressants, that many of the included primary studies were retrospective studies, the heterogeneity among the studies included in the systematic reviews, and the lack of clarity with respect to the strength of the recommendations.