To evaluate the safety of satralizumab in a pooled population of patients with neuromyelitis optica spectrum disorder (NMOSD) from the SAkura studies.

The pooled population included 178 patients (satralizumab, n=104; placebo, n=74). The mean (standard deviation) duration of the double-blind period for safety analysis was longer with satralizumab vs placebo (97.2 [61.2] vs 70.6 [55.8] weeks). Rates of AEs and serious AEs were comparable between satralizumab and placebo groups (AEs: 478.49 vs 506.51 events/100PY, respectively; serious AEs: 14.97 vs 17.98 events/100PY, respectively). Infection rates were lower with satralizumab than placebo (113.04 vs 154.85 events/100PY); there was no increased risk of opportunistic infections. The most common AEs in both treatment groups were urinary tract infection and upper respiratory tract infection. The injection-related reaction (IRR) rate was higher with satralizumab vs placebo (18.58 vs 8.99 events/100PY); IRRs were mostly mild-to-moderate and did not lead to treatment discontinuation. Four patients (3.8%) in the satralizumab group and six (8.1%) in the placebo group withdrew from study due to an AE. No deaths or anaphylactic reactions were reported.

Satralizumab showed a favourable safety profile in patients with NMOSD. The long-term AE data from the ongoing open-label extension periods of both trials will be presented at the congress.