The investigators primarily aim to observe the time to first relapse from initiation of belimumab treatment.~The secondary outcomes are to determine: The safety profile of belimumab in participants with NMO and whether belimumab improves Expanded Disability Status Scale (EDSS), et al.
Neuromyelitis Optica Spectrum Disorders (NMOSD) is associated with a pathological humoral immune response against the aquaporin-4(AQP-4) water channel. Belimumab (Benlysta ®) is a human immunoglobulin G1λ monoclonal antibody that inhibits B-cell survival and differentiation by neutralizing soluble B lymphocyte stimulator. Belimumab may benefit some patients with NMOSD due to the important role of B cells in the pathogenesis of NMOSD. Clincial trials may be needed to observe its efficacy and safety.