Efficacy and Safety of MK-1167 in Participants With Alzheimer's Disease Dementia Taking Stable Donepezil Treatment (MK-1167-007)
Status: Not yet recruiting

The main purpose of this study is to assess the safety and efficacy of MK-1167 administered to participants with Alzheimer's Disease (AD) receiving stable Donepezil treatment.

Eligibility:
- EligibilityCriteria: Inclusion Criteria:  Reports a history of cognitive and functional decline with gradual onset and slow progression for at least 1 year before Screening, that is either corroborated by an informant who knows the subject well or is documented in medical records Meets the criteria for a diagnosis of probable Alzheimer's disease (AD) based on the National Institute of Neurological and Communicative Disorders - Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria for probable AD Is receiving donepezil 10 mg daily for symptomatic treatment of cognitive impairment associated with AD. The dose level must be stable for at least 2 months prior to Screening. If receiving donepezil via a transdermal system (ie, patch), it should be a 10-mg/day dose and should switch prescription to a 10-mg oral daily dose, before enrollment Has a reliable and competent trial partner/caregiver who has a close relationship with the participant, has face-to-face contact at least 3 days a week for a minimum of 6 waking hours a week, and is willing to accompany the participant, if desired, to study visits  Exclusion Criteria:  History of clinically significant endocrine, gastrointestinal, cardiovascular, hematological, hepatic, immunological, renal, respiratory, genitourinary, or major neurological (including stroke and chronic seizures) abnormalities or diseases that are not under medical control over the past 2 months. Mentally or legally incapacitated, has significant emotional problems at the time of prestudy (screening) visit or expected during the conduct of the study or has a history of clinically significant psychiatric disorder of the last 5 years. Participants who have had situational depression may be enrolled in the study at the discretion of the investigator. History of cancer (malignancy). Participants with adequately treated disease deemed as "cured," or who, in the opinion of the study investigator, are highly unlikely to sustain a recurrence for the duration of the study, may be enrolled at the discretion of the investigator and Sponsor. History of significant multiple and/or severe allergies (eg, food, drug, latex allergy), or has had an anaphylactic reaction or significant intolerability (ie, systemic allergic reaction) to prescription or nonprescription drugs or food. Had a major surgery and/or donated or lost 1 unit of blood (approximately 500 mL) within 4 weeks prior to the prestudy (screening) visit. Unable to refrain from or anticipates the use of any medication, including prescription and nonprescription drugs or herbal remedies beginning approximately 2 weeks (or 5 half-lives) prior to administration of the initial dose of study intervention, throughout the study, until the poststudy visit. There may be certain protocol-specified medications that are permitted. The participant is a smoker and/or has used nicotine or nicotine-containing products (eg, nicotine patch and electronic cigarette) within 3 months of screening. Consumes greater than 3 servings of alcoholic beverages per day. Participants who consume 4 servings of alcoholic beverages per day may be enrolled at the discretion of the investigator. The participant is a regular user of cannabis, any illicit drugs or has a history of drug (including alcohol) abuse within approximately 2 years. - HealthyVolunteers: No - Gender: All - MinimumAge: 50 Years - MaximumAge: 90 Years - StdAgeList: Adult, Older Adult