This is a multi-center, two-part study of ION363 in up to 77 participants. Part 1 will consist of participants that will be randomized in a 2:1 ratio to receive a multi-dose regimen of ION363 or placebo for a period of 61 weeks, followed by Part 2, in which participants will receive ION363 for a period of 85 weeks.
The primary purpose of this study is to evaluate the clinical efficacy of ION363 on clinical function and survival in carriers of fused in sarcoma mutations with amyotrophic lateral sclerosis (FUS-ALS).