Roche has published data from the Phase III SAkuraSky study of the investigational medicine satralizumab for the treatment of neuromyelitis optica spectrum disorder (NMOSD).
People with NMOSD experience unpredictable, severe relapses that directly cause cumulative, permanent, neurological damage and disability. The condition is often misdiagnosed as multiple sclerosis.
Satralizumab inhibits interleukin-6 (IL-6) signalling, which is believed to play a key role in the inflammation that occurs in people with NMOSD. Satralizumab can be self-administered every four weeks by subcutaneous injection.
Published in the New England Journal of Medicine (NEJM), results highlight that in the overall study population, 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.
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.
Notably, the intention-to-treat (ITT) population studied included both aquaporin-4 (AQP4-IgG) seropositive and seronegative patients, reflecting a real-world population of adolescents and adults (age 13-73 years) with NMOSD. People who are AQP4-IgG seropositive tend to experience a more severe disease course.
In the AQP4-IgG seropositive subgroup analysis, three of 27 patients (11%) treated with satralizumab experienced a PDR compared to 12 of 28 patients (43%) treated with placebo.
In the AQP4-IgG seronegative subgroup analysis, five of 14 patients (36%) treated with satralizumab experienced a PDR compared to six of 14 patients (43%) receiving placebo.
Overall, the proportion of patients with serious adverse events was similar between the satralizumab and placebo treatment groups. A lower rate of infections (including serious infections) was observed in patients treated with satralizumab compared with the placebo group.
Most adverse events were mild-to-moderate, and the most common adverse events in the satralizumab group were upper respiratory tract infection, nasopharyngitis (common cold) and headache.
In October 2019, the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA) accepted the marketing applications for satralizumab for the treatment of NMOSD, and the EMA granted Accelerated Assessment.
The EMA’s Committee for Medicinal Products for Human Use (CHMP) recommendation and the FDA decision are expected in 2020.