Satralizumab for Neuromyelitis Optica Spectrum Disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing autoimmune disease that often leads to disability. Satralizumab, a monoclonal antibody that antagonizes interleukin-6 (IL6), was investigated in this phase 3, randomized, double-blind, placebo-controlled, company-sponsored study. Investigators enrolled 83 patients with NMOSD to receive satralizumab or placebo subcutaneously at baseline, 2 weeks, and every 4 weeks thereafter. The double-blind period was planned until the occurrence of 26 protocol-defined relapses.

Relapses occurred in 8 (20%) of 41 satralizumab recipients and 18 (43%) of 42 placebo recipients. Relapses were reduced by 62% (hazard ratio, 0.38). At 48 weeks, 89% on satralizumab and 66% on placebo were relapse-free. I…