This project investigates cerebrospinal fluid (CSF) proteome changes in adults with spinal muscular atrophy (pwSMA) treated with the antisense oligonucleotide nusinersen. A label-free quantitative proteomic analysis was conducted on CSF samples from a subset of pwSMA (n=7) classified as clinical responders or non-responders based on motor function changes under therapy. The aim was to identify proteins differentially abundant between these groups. Candidate biomarkers emerging from this discovery phase—Neuronal Pentraxin 2 (NPTX2), Contactin 5 (CNTN5), and Anthrax Toxin Receptor 1 (ANTXR1)—were selected for follow-up analysis using orthogonal validation methods in an independent cohort. This dataset contains the primary CSF proteomic data used for the identification of potential treatment-associated protein changes in adult SMA.