In ALS, TfR antibody-modified exosomes carrying SOD1 antisense oligonucleotides (ASOs) achieved 15% drug concentration in cerebrospinal fluid and delayed motor neuron degeneration by 30% in SOD1-G93A transgenic mice (Wang et al., 2023; Yang and Zhang, 2022). This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.