Real-world data on the effect of long-term treatment with nusinersen over > 4 years in a cohort of Swiss patients with spinal muscular atrophy

Abstract

Introduction

Current disease-modifying treatments for spinal muscular atrophy (SMA) have been shown to significantly improve the course of the disease, but data on long-term real-world outcomes remain scarce.

Methods

This prospective multicentre, observational study investigated 28 patients treated with nusinersen for 4.1–6.2 years. Motor function was assessed with the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), Hammersmith Functional Motor Scale (Expanded) (HFMS/E) and the Revised Upper Limb Module (RULM). Patient global impression of improvement scale, respiratory and nutritional support were assessed.

Results

Eight patients were 0–2.5 years old at treatment start and median gain of motor scores was 31.5 points in the CHOP-INTEND and 10 points in the HFMS/E. Three patients started part-time non-invasive ventilation and/or nutritional support during observation period. Fourteen patients were 3.5–16 years old and showed a median gain of 1 point in the HFMS/E. Four patients required non-invasive ventilation and/or nutritional support at treatment start, and three started support during observation period. Six patients were aged 16–45 years old and showed a median gain of 3.5 points in the HFMS/E. None needed chronic respiratory or nutritional support. After one year, 84 %, and after 4 years of treatment, 54 % of patients felt their condition had improved in the last 6 months.

Conclusion

Our data confirm sustained gains of motor function in early-treated patients and disease stabilisation in patients in the chronic phase under nusinersen treatment.