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

摘要

Background Satralizumab, a humanised monoclonal antibody targeting the interleukin-6 receptor, reduced the risk of relapse in patients with neuromyelitis optica spectrum disorder (NMOSD) when added to immunosuppressant therapy. This study assessed the safety and efficacy of satralizumab monotherapy in patients with the disorder. Methods In this phase 3, double-blind, placebo-controlled, parallel-group trial, we enrolled adults aged 18-74 years with aquaporin-4 antibody seropositive or seronegative NMOSD at 44 investigational sites in 13 countries. Eligible participants had experienced at least one documented NMOSD attack or relapse in the past 12 months and had a score of 6.5 or less on the Expanded Disability Status Scale. Exclusion criteria included clinical relapse 30 days or fewer before baseline. Participants were randomly assigned (2:1) to receive satralizumab 120 mg or visually matched placebo subcutaneously at weeks 0, 2, 4, and every 4 weeks thereafter. Taking immunosuppressants concomitantly was prohibited. The primary endpoint was time to the first protocol-defined relapse, based on the intention-to-treat population and analysed with stratification for two randomisation factors (previous therapy for prevention of attacks and nature of the most recent attack). Safety was assessed in all participants who received at least one dose of satralizumab or placebo. The double-blind phase was due to last until 44 protocol-defined relapses occurred or 1.5 years after random assignment of the last patient enrolled, whichever occurred first; participants could enter an open-label phase after the occurrence of a protocol-defined relapse or at the end of the double-blind phase. The study is registered with ClinicalTrials.gov, NCT02073279.