Therapy Improves Motor Function in Non-Ambulant Pediatric Patients With SMA

Treatment with nusinersen was associated with clinically meaningful improvements in motor function in non-ambulant pediatric patients with spinal muscular atrophy (SMA), according to findings published in the Orphanet Journal of Rare Diseases.

“Most data on therapeutic efficacy are available for the infantile-onset SMA. For patients with SMA type 2 and type 3, there is still a lack of sufficient evidence and long-term experience for nusinersen treatment,” researchers said.

To fill the gap, study authors used data from the SMArtCARE registry to follow 256 non-ambulant patients with SMA type 2 and 3 for up to 38 months. Participants were included if they were younger than 18 years of age when they initiated nusinersen.

The Hammersmith Functional Motor Scale Expanded (HFMSE) and Revised Upper Limb Module (RULM) were used to measure changes in motor function. Approximately one-third of patients showed clinically meaningful improvements in RULM, while 24.6% saw improvements in HFMSE. No motor milestones were lost during the study, but 8.6% of patients gained a new motor milestone, according to the findings.

“Only 4.3% of patients showed a clinically meaningful worsening in HFMSE and 1.2% in RULM score,” investigators said.

Nusinersen had no impact on the need for ventilator support or tube feeding, and there were no new safety signals reported.

“Our data confirm clinical trial data, while providing longer follow-up, an increased number of treated patients, and a wider range of age and disease severity,” researchers concluded.

Reference:
Pechmann A, Behrens M, Dörnbrack K, et al. Improved upper limb function in non-ambulant children with SMA type 2 and 3 during nusinersen treatment: A prospective 3-years SMArtCARE registry study. Orphanet J Rare Dis. 2022;17(1):384. doi:10.1186/s13023-022-02547-8