Phase III clinical study of SA 237 in neuromyelitis optica spectrum disorder published in NEJM.- Chugai Pharma

Chugai Pharmaceutical announced that the results of the SAkuraSky Study (NCT02028884), a global phase III clinical study of SA 237 (satralizumab) were published on November 27 in the online version of The New England Journal of Medicine (NEJM). Satralizumab is an anti-IL6 receptor humanized recycling antibody under development for the treatment of neuromyelitis optica spectrum disorder (NMOSD). The phase III study examined the efficacy and safety of satralizumab added to baseline therapy in patients with NMOSD.

In SAkuraSky Study, only eight of 41 patients (20%) treated with satralizumab in combination with baseline immunosuppressant therapy experienced a protocol-defined relapse (PDR) compared to 18 of 42 patients (43%) treated with placebo in combination with baseline therapy (HR=0.38, 95% CI: 0.16-0.88; p=0.02 [stratified log-rank test]) in the overall population, representative of NMOSD patients (including anti-AQP4-IgG antibody seropositive and seronegative patients). Importantly, 89%, 78% and 74% of patients on satralizumab in combination with baseline therapy were relapse-free at weeks 48, 96 and 144 compared to 66%, 59% and 49% with placebo in combination with baseline therapy. The proportion of serious adverse events was similar between the satralizumab and placebo treatment groups.

See: "Trial of Satralizumab in Neuromyelitis Optica Spectrum Disorder" Takashi Yamamura et al. N Engl J Med 2019; 381:2114-2124 DOI: 10.1056/NEJMoa1901747

Comment: Satralizumab inhibits IL-6 signaling, which is believed to play a key role in the inflammation that occurs in people with NMOSD, leading to damage and disability. People with NMOSD experience unpredictable, severe relapses that directly cause cumulative, permanent neurological damage.