Nusinersen in adult patients with 5q spinal muscular atrophy: a multicenter observational cohorts’ study

Abstract

ABSTRACTObjectiveTo assess safety and efficacy of nusinersen in adult 5q spinal muscular atrophy (SMA) patients.MethodsPatients older than 15 years and followed at least for 6 months with one motor scale (Hammersmith Functional Motor Scale Expanded, HFMSE; Revised Upper Limb module, RULM) in five referral centers were included. Clinical and patients’ global impression of change (CGI-C and PGI-C) were recorded in treated patients at the last visit. Functional scales (Egen Klassification, EK2; Revised Amyotrophic Lateral Sclerosis Functional Rating Scale, ALSFRS-R) and the percent-predicted forced vital capacity were collected when available.ResultsSeventy-nine SMA patients (39 treated with nusinersen) were included. Compared with untreated patients, treated patients showed a significant improvement of 2 points (±0.46) in RULM (p<0.001) after six months. After a mean follow-up of 16 months, nusinersen treatment was associated with a significant improvement in HFMSE (OR=1.15, p=0.006), 6MWT (OR=1.07, p<0.001), and EK2 (OR=0.81, p=0.001).Compared with untreated patients, more treated patients experienced clinically meaningful improvements in all scales, but these differences were statistically significant only for RULM (p=0.033), ALSFRS-R (p=0.005), and EK2 (p<0.001). According to the CGI-C and PGI-C, 64.1% and 61.5% of treated patients improved with treatment. Being non-sitter was associated with less response to treatment, while longer time of treatment was associated with better response. Most treated patients (77%) presented at least one adverse event, mostly mild.ConclusionsNusinersen treatment associates to some improvements in adult SMA patients. Most severely affected patients with complex spines are probably those with the most unfavorable risk-benefit ratio.