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

The purpose of this study was to assess the safety, tolerability, and pharmacokinetic (PK) of TAK-071 when administered as single rising dose (SRD) and multiple rising dose (MRD) orally in healthy participants and participants with mild cognitive impairment (MCI) or mild Alzheimer disease (AD).

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.

Eligibility Criteria:
Inclusion Criteria:

1. Man or woman who weighs at least 50 kg and has a body mass index (BMI) from 18.0 to 30.0 kg/m\^2, inclusive, at Screening. Participants should be aged 18 to 55 years, inclusive (nonelderly at the time of informed consent and first study drug dose) for Cohorts 1 to 12, and 17 to 22; 20 to 55 years, inclusive, for Cohorts 13 to 15; and 55 to 90 years, inclusive, for participants in Cohort 16.
2. For Cohorts 13 to 15 only: First-generation Japanese, defined as having been born in Japan of Japanese parents and Japanese grandparents and living no more than 10 years outside of Japan, with no significant change in lifestyle, including diet, while living outside of Japan.
3. Cohort 16 only: Healthy elderly or participants with MCI or mild AD, who must have Mini Mental State Examination (MMSE) score of 18 to 30, inclusive or 18 to 26 inclusive, respectively, and no biomarker data to contradict this diagnosis. Participants with documented diagnosis of MCI or mild AD must be receiving ongoing donepezil therapy (10 mg) in the evening for a minimum of 21 days prior to Check-in (Day -1) or must consent to take donepezil dose titrated to at least 21 days of treatment with 10 mg QD prior to Check-in.

Exclusion Criteria:

1. Has clinically significant (Cohorts 1 to 15 and 17 to 22) or uncontrolled (Cohort 16) neurologic, cardiovascular, pulmonary, hepatic, renal, metabolic, gastrointestinal (GI), urologic, immunologic, endocrine, or psychiatric disease or other abnormality (other than the disease being studied), which may impact the ability of the participant to participate or potentially confound the study results.
2. Has a history of type 1 diabetes (Cohorts 1 to 22) or type 2 diabetes (Cohorts 1 to 15, 17 to 22) or hemoglobin A1c \>6.5% at Screening. Note: participants with controlled (hemoglobin A1c \<7.0% at Screening) type 2 diabetes in Cohort 16 may participate in the study.
3. Has a risk of suicide or suicidal ideation with intent and plan according to the investigator's clinical judgment (affirmative answer to questions 4 and 5 of the ideation section of the Columbia-Suicide Severity Rating Scale) or has made a suicide attempt in the previous 6 months.
4. Cohort 16 only: Any significant neurologic disease (other than suspected incipient or mild AD), such as Parkinson disease, stroke, transient ischemic attack, multi-infarct dementia, Huntington disease, head trauma with clinically significant cognitive sequelae, or chronic central nervous system infection, per investigator discretion.
5. Has current or recent (within 6 months) GI disease that would be expected to influence the absorption of drugs (ie, a history of malabsorption, any surgical intervention known to impact absorption \[eg, bariatric surgery or bowel resection\], esophageal reflux, peptic ulcer disease, erosive esophagitis, or frequent \[more than once per week\] occurrence of heartburn).