Study of TAK-071 in Healthy Participants and Participants With Mild Cognitive Impairment/Mild Alzheimer Disease and Relative Bioavailability (BA) and Food Effect of TAK-071 in Healthy Participants

TAK-071 was being tested to find a safe and well-tolerated dose in healthy participants (non-Japanese and Japanese) and participants with MCI or mild AD (non-Japanese). The study enrolled 179 participants. The study consisted of 4 parts: Single-rising dose (SRD) part (Cohorts 1-6, and 18-22), multiple-rising dose (MRD) part (Cohorts 7-15), Cohort 16 with 2-arm parallel design, and Cohort 17 relative bioavailability and food effect 3 period crossover design. Participants in each cohort were randomized to receive treatment with TAK-071 or matching placebo using drug-in-capsule (DIC) in the morning following a minimum fast of 8 hours. In Cohort 16, participants were assigned to 1 of 2 possible treatments, TAK-071 or matching placebo. In Cohort 17, participants were assigned to 1 of 3 treatment sequences (ABC, BCA, or CAB) with treatment A being fasted state and capsule formulation, treatment B being fasted state and tablet formulation, and treatment C being fed state and tablet formulation. In Cohorts 20-22, participants were administered as a single dose of TAK-071 or placebo on Day 1, and a single dose of donepezil or placebo approximately 24 hours later on Day 2. This multi-center trial was conducted in United States. The overall time to participate in this study was approximately 41 days. Participants made multiple visits to the clinic and were also contacted for the follow-up through the telephone.