Satralizumab: long-term efficacy in neuromyelitis optica spectrum disorder patients

Sustained efficacy was observed for aquaporin-4-IgG-seropositive (AQP4-IgG+) NMOSD in the open-label extension period of a Phase 3 study.

Most patients were free from severe relapse

Satralizumab, a subcutaneously administered IL-6 receptor antagonist, significantly reduced the risk of relapse in patients with AQP4-IgG+ NMOSD in two double-blind, randomised controlled, Phase 3 trials (SAkuraSky (NCT02028884); SAkuraStar (NCT02073279)). In both trials, a favourable safety profile was observed in the double-blind phase. The current study assessed the long-term efficacy of satralizumab. Patients who received ≥ 1 dose of satralizumab in the double-blind phase, or in the open label extension (OLE) period were included in the analysis (n=111).

Satralizumab dose in the OLE period was 120 mg, administered every 4 weeks. Efficacy endpoints were investigator-assessed protocol-defined relapses (iPDRs), severe iPDRs (≥ 2-point increase on the expanded disability status scale (EDSS)), and sustained EDSS score worsening (≥ 24 weeks) at week 192. Dr Ingo Kleiter (Ruhr-Universität Bochum, Germany) presented the findings of the OLE study. At a median duration of approximately 4 years exposure to satralizumab, 71% (SAkuraSky) and 73% (SAkuraStar) of the patients were free from relapse.

This corresponded to a mean annualised iPDR rate of 0.20. In addition, most patients were free from severe relapse (SAkuraSky 90%; SAkuraStar 91%). Sustained EDSS worsening was observed in 10% (SAkuraSky) and 14% (SAkuraStar) of the patients. No new safety issues emerged with long-term satralizumab treatment in this population.

Reference
  1. Kleiter I, et al. Long-term efficacy of satralizumab in aquaporin-4-IgG seropositive neuromyelitis optica spectrum disorder (NMOSD). Results from the open-label extension periods of SAkuraSky and SAkuraStar. P024, ECTRIMS 2021 Virtual Congress, 13–15 October.