Comparative efficacy of risdiplam and nusinersen in Type 2 and 3 spinal muscular atrophy patients: A cohort study using real-world data.

Background: Three medications have been approved for spinal muscular atrophy (SMA) treatment. No head-to-head clinical trials have directly compared the efficacy of nusinersen and risdiplam. We compare the efficacy of them in Type 2 and 3 SMA patients, with 6 months of follow-up.

Methods: A multicenter cohort study was conducted. Demographic, genetic and clinical findings containing Hammersmith Functional Motor Scale Expanded (HFMSE) and revised upper limb module (RULM) scales were gathered. An increase of at least 3 points in HFMSE and RULM scores was considered a positive response.

Results: 73 (58.4%) children received risdiplam, and 52 (41.6%) received nusinersen non-randomly, based on clinical decision. The difference in HFMSE and RULM scores compared to the baseline was significant in both groups (P-value <0.001). However, there was no significant difference between mean difference changes in HFMSE and RULM scores between the two groups. 80.4% of patients in the risdiplam group and 72% in the nusinersen group achieved the 3-point cutoff after 6 months, and there is no significant difference between the two groups (P-Value:0.33).

Conclusions: This study showed that both medications significantly changed the HFSME and RULM after 3 and 6 months of follow-up. However, there was no significant difference between the two drugs according to the HFSME.