Nusinersen treatment significantly improves hand grip strength, hand motor function and MRC sum scores in adult patients with spinal muscular atrophy types 3 and 4

Background Nusinersen recently became available as the first treatment for Spinal Muscular Atrophy (SMA) and data on its effectiveness and safety in adult SMA patients are still scarce. Methods We evaluated the effectiveness and safety of nusinersen treatment during 14 months in 16 adult patients with SMA types 3 and 4 in a prospective study, and retrospectively detailed the natural history of 48 adult SMA patients types 2, 3 and 4. Results Hand grip strength ( p = 0.03), hand motor function ( p = 0.04) as assessed by a sub-score of the Revised Upper Limb Module (RULM) and the Medical Research Council (MRC) sum score ( p = 0.04) improved significantly at month 14. Importantly, the MRC sum score had declined significantly ( p