Neurodegenerative Alzheimer's Disease and Amyotrophic Lateral Sclerosis (NADALS) Basket Trial

This is an open-label, biomarker-driven basket trial of baricitinib in people with subjective cognitive disorder, mild cognitive impairment, Alzheimer's disease (AD), Amyotrophic lateral sclerosis (ALS), or asymptomatic carriers of an ALS-related gene, such as a hexanucleotide expansion in the C9ORF72 gene, with evidence of abnormal inflammatory signaling in cerebrospinal fluid (CSF) at baseline. Each participant will be treated with baricitinib for 24 weeks; no placebo will be given. Participants will receive baricitinib 2 mg per day by mouth for the first 8 weeks and baricitinib 4 mg per day by mouth for the remaining 16 weeks. This proof of concept trial will ascertain whether baricitinib at 2 mg per day, 4 mg per day, or both reaches therapeutic levels in the CSF and suppresses inflammatory biomarkers associated with type I interferon signaling among the study participants.