Safety and efficacy of satralizumab monotherapy in neuromyelitis optica spectrum disorder: a randomised, double-blind, multicentre, placebo-controlled phase 3 trial

RCT (n=168) found that this monoclonal antibody targeting IL6 reduced rate of relapse vs. placebo in overall trial population (protocol-defined relapses in 19 [30%] on satralizumab and 16 [50%] on placebo; HR 0.45, 95% CI 0.23–0.89; p=0.018), with a favourable safety profile.

SPS commentary:

This is one of two large, placebo-controlled randomised trials in The Lancet Neurology evaluating the use of monoclonal antibodies targeting IL6 for the prevention of relapse in patients with NMOSD.


The other study (n=118 in China) evaluated tocilizumab (8mg/kg IV every 4 weeks) and found that it significantly reduced the risk of a subsequent NMOSD relapse compared with oral azathioprine (2–3 mg/kg per day), with median time to first relapse of 78.9 weeks vs 56.7 weeks; respectively (p=0.0026).


A commentary notes that the results of these and a further trial of satralizumab demonstrate a benefit of reduced hazard of relapse of between 55% and 74%. Two additional placebo-controlled trials in patients with NMOSD were published in 2019 using drugs that target different immunopathological mechanisms: the first was eculizumab, a C5 complement inhibitor, which reduced the risk of relapse by 94% and the second was inebilizumab, a CD19 B-cell depleting monoclonal antibody that reduced the risk of relapse by 73%. It suggests that the safety concerns regarding these approaches are all substantially outweighed by the benefit of preventing NMOSD relapses.


The Lancet Neurology

Resource links:


Tocilizumab study