Five-year disease-modifying therapeutic experience of 102 Chinese paediatric 5q-spinal muscular atrophy: a retrospective analysis

TL;DR

A study of 102 Chinese children with SMA found that disease-modifying therapies improved motor function and survival, but also highlighted complications and the importance of early treatment.

Contribution

This study provides long-term clinical outcomes of disease-modifying therapies for SMA in a large pediatric cohort in China.

Findings

Patients showed significant motor function gains over five years of treatment.

Type 1 patients experienced weight loss and compromised growth after treatment.

Early initiation of therapy was linked to better outcomes and fewer complications.

Abstract

5q-spinal muscular atrophy (SMA) is a fatal autosomal recessive disease characterized by the progressive muscle weakness and atrophy. In this retrospective study, we described the long-term clinical outcomes of novel disease-modifying therapies (DMTs) for 5q-spinal muscular atrophy, drawing on experience from southern China. This is a single-centre large cohort which enrolled 102 paediatric patients confirmed with 5q-spinal muscular atrophy at Guangzhou Women and Children’s Medical Center from 2019 to 2024. One hundred and two patients were included, 24 were classified as SMA type 1, 56 with type 2 and 22 with type 3. One hundred per cent of the patients received nusinersen, with 31 (30.3%) patients starting risdiplam and 2 patients transitioning to zolgensma therapy. Over the 5-year treatment and follow-up period (2019–24), the survival rate reached 97.08%. One child with SMA type 1 and two with SMA type 2 died while receiving nusinersen monotherapy. Compared with baseline, the enrolled SMA patients exhibited statistically significant motor function gains. Nevertheless, type 1 patients experienced weight loss, while linear growth was compromised in both type 1 and type 2 patients after treatment. Serum insulin-like growth factor-1 levels rose modestly in types 1 and 2, but the increase did not reach statistical significance. Respiratory tract infections, malnutrition, scoliosis and fracture are the main complications and potential life-threatening risk factors during DMTs. Moreover, longer diagnostic to treatment intervals were significantly and inversely associated with motor function gains and directly associated with higher complication rates. This retrospective study confirms the effectiveness of nusinersen and risdiplam for 5q-spinal muscular atrophy and highlights the critical importance of early initiation of DMTs.

Jiang et al. showed that 5-year follow-up data from 102 children with 5q-spinal muscular atrophy who received disease-modifying therapy revealed improvements in motor function, growth status and frequency of complications, thereby underscoring the highly variable clinical outcomes observed in this patient cohort.

Graphical Abstract

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