The treatment of tofersen did not result in statistically significant improvements on clinical endpoints in a Phase III study involving patients with SOD1 amyotrophic lateral sclerosis; however, tofersen was found to be beneficial across clinical outcome measures of respiratory function, muscle strength, and quality of life during the 28-week treatment period, and these improvements continued during the open-label extension, including improvements on clinical endpoints at week 52. This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.