Nusinersen does not improve lung function in a cohort of children with spinal muscular atrophy - A single-center retrospective study.

OBJECTIVE

To examine the effect of intrathecal application of nusinersen on the respiratory function in terms of vital capacity in pediatric patients with spinal muscular atrophy (SMA). SMA is characterized by on-going muscular atrophy and weakness that lead to respiratory insufficiency. In recent years therapy with nusinersen has been shown to improve motor function in patients with SMA.

METHODS

We retrospectively analyzed data from 12 pediatric patients (aged 4-12 years) with SMA II or III (7 walkers, 5 sitters) treated with nusinersen. We examined forced vital capacity (FVC) at baseline (i.e., before treatment) and 180 and 300 days after initiation of treatment.

RESULTS

No significant difference in the ranks of FVC of patients with SMA at baseline and day 300 was found and, thus, stable FVCs are implied (n = 6; Z = - 0.105, pexact = 1.000; Medianbaseline = 96.0%, 95%-CI [86.5, 110.5]; Medianday300 = 96.0%, 95%-CI [92.0, 109.5]; s. Table 1). This also applied to the comparison between baseline and day 180 (n = 7; Z = 0.00, pexact = 1.00; Medianbaseline = 93.0%, 95%-CI [85.0, 110.0]; Medianday180 = 91.0%, 95%-CI [72.0, 118.0]) and day 180 and 300 (n = 9; Z = - 0.533, pexact = .652; Medianday180 = 95.0%, 95%-CI [72.0, 118.0]; Medianday300 = 90.0%, 95%-CI [74.0, 105.0]).

CONCLUSION

Nusinersen therapy alone may not improve lung function of pediatric patients with SMA type II or III.