Reply to letter to the editor "Regarding nusinersen and other therapeutic strategies for improved motor function".

We would like to thank Pashin et al. [ [1] Pashin K.P. Sekhar T.C. Treating neurodegenerative disease: nusinersen and other therapeutic strategies for improved motor function. Brain Dev. 2023; 45: 360-361 Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar ] for their insightful comments on our study [ [2] Shimizu-Motohashi Y. Chiba E. Mizuno K. Yajima H. Ishiyama A. Takeshita E. et al. Muscle impairment in MRI affect variability in treatment response to nusinersen in patients with spinal muscular atrophy type 2 and 3: a retrospective cohort study. Brain Dev. 2023; 45: 161-170 Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar ]. As shown in our study, nusinersen demonstrated treatment variability to nusinersen in patients with spinal muscular atrophy (SMA) types 2 and 3. To improve this outcome, we strongly agree that additional approaches, such as combinations or novel therapeutic strategies, should be investigated.