Long-term safety of satralizumab consistent with double-blind periods

In patients with neuromyelitis optica spectrum disorder (NMOSD), satralizumab continued to be well tolerated and to have a favourable safety profile when open-label extension period data were included in the analysis [1]. The overall satralizumab treatment data were consistent with the double-blind periods.

Satralizumab is a humanised monoclonal antibody that binds to and blocks the IL-6 receptor and was shown to reduce NMOSD relapse risk in both the SAkuraSky (satralizumab in combination with baseline immunosuppressants), and the SAkuraStar (satralizumab monotherapy) phase 3 trials. The pooled double-blind population included 178 patients (satralizumab, n=104; placebo, n=74); 166 patients received satralizumab in the open-label extension period. The combined double-blind/extension period was defined as the overall satralizumab treatment period, in which mean exposure was around 130 weeks.

In the double-blind period, rates of adverse events (AEs) and serious AEs in the satralizumab arms were comparable to those with placebo. Infection rates were lower with satralizumab. In the double-blind and overall treatment periods, AE, serious AE, and infection rates were comparable (see Table). An AE led 4 patients (3.8%) on satralizumab and 6 (8.1%) on placebo to withdraw from the double-blind period. The injection-related reaction (IRR) rate was higher with satralizumab. IRRs were mostly mild-to-moderate and did not lead to treatment discontinuation.

Table. Pooled adverse event rates across the SAkuraSky and SAkuraStar trials [1]

AE, adverse event; OST, overall satralizumab treatment, PY, patient year.

1. 1. Greenberg BM, et al. Abstract EPR2140, EAN 2020.