The study was done to retrospectively investigate safety and efficacy of nusinersen in a large cohort of adult Italian patients with SMA.

116 patients were included in the study with median age at first administration of 34 years (range 18–72). The HFMSE in patients with SMA3 increased significantly from baseline to T6, T10 and T14. HFMSE changes were independently significant in SMA3 sitter and walker subgroups. The Revised Upper Limb Module (RULM) in SMA3 significantly improved between T0 and T14 (median +0.5, p=0.012), with most of the benefit observed in sitters. Conversely, patients with SMA2 had no significant changes of median HFMSE and RULM between T0 and the following time points, although a trend for improvement of RULM was observed in those with some residual baseline function. The rate of patients showing clinically meaningful improvements increased from 53% to 69% from T6 to T14.

The evidence of nusinersen safety and efficacy in adult SMA2 and SMA3, with the latter appearing to be cumulative over time. In patients with extremely advanced disease, effects on residual motor function are less clear.