Promising results of novel NMOSD treatments

There are as yet no registered treatments for neuromyelitis optica spectrum disorders (NMOSD), but that will change soon. Three monoclonal antibodies –inebilizumab, satralizumab, and eculizumab– submitted promising safety and efficacy results in terms of relapse prevention in the past year. At the EAN 2019, efficacy and safety results of inebilizumab and satralizumab were presented [1,2].

Inebilizumab, an anti-CD19 monoclonal antibody, reduced attacks, disability progression, hospitalisations, and new lesions in NMOSD compared with placebo in the randomised controlled period of the N-MOmentum pivotal study [1]. The drug was well-tolerated, with adverse event (AE) rates similar to placebo. A total of 230 patients were randomised to inebilizumab (n=174) or placebo (n=56) monotherapy for 6.5 months. Of those, 91% were aquaporin 4-IgG seropositive (AQP4-IgG+). Study recruitment was stopped early because of clear evidence of efficacy. Inebilizumab reduced the risk of attacks by 72.8% (P<0.001). This percentage was even higher in the AQP4-IgG+ population: 77.3% (P<0.001). During the randomised controlled period, 87.9% of participants did not have a single attack. The most common AEs included urinary tract infections and infusion-related reactions, without any difference between groups.

Additional analyses of the SAkuraSky study revealed that satralizumab, an IL-6R inhibitor, significantly reduced relapse risk, especially in AQP4-IgG+ patients [2]. The 83 participating NMOSD patients had been randomly assigned to receive satralizumab 120 mg or placebo at week 0, 2, and 4 and every 4 weeks thereafter, added to stable immunosuppressant treatment. Satralizumab significantly reduced risk of protocol-defined relapse by 62% vs placebo (P=0.0184). Relapse risk was reduced by 79% with satralizumab in AQP4-IgG+patients (n=55). The proportion of relapse-free patients at weeks 48 and 96 were 91.5% and 91.5% with satralizumab, and 59.9% and 53.3% with placebo, respectively. In AQP4-IgG- patients, relapse risk was reduced by 34% vs placebo. In the overall study population, annualised relapse risk was 0.11 in the satralizumab group and 0.32 in the placebo group.

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   1. Cree B, et al. EAN 2019, O4122.
   2. Yamamura T, et al. EAN 2019, O4113.

Posted on 27 August, 201916 February, 2024