Real-world evidence of Nusinersen treatment for patients with spinal muscular atrophy in the Kingdom of Saudi Arabia: Initial insights from the Saudi national spinal muscular atrophy program.

OBJECTIVES: To assess the clinical and functional outcomes of 110 patients with spinal muscular atrophy (SMA) program who received nusinersen treatment in the Kingdom of Saudi Arabia (KSA). METHODS: Motor assessments were performed using the Children's Hospital of Philadelphia infant test of neuromuscular disorder (CHOP-INTEND) and Hammersmith infant neurological examination (HINE) for type 1 SMA, the Hammersmith Functional Motor Scale-Expanded (HFMSE) for types 2 and 3 SMA; the 6-minute walk test (6MWT) for ambulant type 3 SMA, and the revised upper limb module (RULM) for types 2 and 3 SMA. RESULTS: Data included all SMA types (type 1, 2.72%; type 2, 27.27%; type 3, 69.09%). The median (IQR) ages at diagnosis, therapy initiation, and symptoms onset were 9.07 (3.67-17.28), 12.04 (5.39-20.29), and 2.25 (0.75-4.00) years, respectively. The median (IQR) HFMSE score was 34 (12.00-46.00) at baseline (n=58 patients) and 29.00 (14.50-50.50) at month 20 (n=33 patients). Clinically meaningful improvement was observed in 23 patients, including 12 with an improvement >4 points. CONCLUSION: The study demonstrates that baseline and follow-up data from multiple motor and functional assessment scales were essential for evaluating disease progression and treatment response in SMA.