NCT03740178

Brief Summary

This study will evaluate the safety, tolerability, and pharmacokinetics of MK-4334 administered once daily (QD) in participants with Alzheimer's clinical syndrome receiving a stable, daily dose of donepezil 10 mg, taken orally (PO). This includes participants with symptoms of mild cognitive impairment (MCI) or mild to moderate Alzheimer's disease (AD). It is hypothesized that the true geometric mean minimum plasma concentration at 24 hours (C24) is at least 60 nM at steady state in the presence of steady-state donepezil 10 mg.

Trial Health

15
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Timeline
Completed

Started Sep 2019

Shorter than P25 for phase_1

Status
withdrawn

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

November 12, 2018

Completed
2 days until next milestone

First Posted

Study publicly available on registry

November 14, 2018

Completed
11 months until next milestone

Study Start

First participant enrolled

September 27, 2019

Completed
5 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

February 28, 2020

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

February 28, 2020

Completed
Last Updated

April 25, 2025

Status Verified

April 1, 2025

Enrollment Period

5 months

First QC Date

November 12, 2018

Last Update Submit

April 22, 2025

Conditions

Outcome Measures

Primary Outcomes (2)

  • Number of Participants Experiencing an Adverse Event (AE)

    An AE is any unfavorable and unintended sign, symptom, or disease (new or exacerbated) in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study treatment. For each arm, the number of participants experiencing an AE will be assessed.

    Up to 42 days

  • Number of Participants Discontinuing Study Treatment due to an Adverse Event

    An AE is any unfavorable and unintended sign, symptom, or disease (new or exacerbated) in a clinical study participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. For each arm, the number of participants discontinuing study treatment due to an AE will be assessed.

    Up to 14 days

Secondary Outcomes (7)

  • Plasma Steady State Concentration at 24 Hours (C24) of MK-4334

    Day 14: Pre-dose and 24 hours after MK-4334 administration

  • Plasma Steady State Area Under the Concentration-Time Curve from 0 to 24 hours (AUC0-24) of MK-4334

    Day 14: Pre-dose and 0.5, 1, 2, 3, 4, 6, 8, 12, and 24 hours after MK-4334 administration

  • Plasma Steady State Maximum Concentration (Cmax) of MK-4334

    Day 14: Pre-dose and 0.5, 1, 2, 3, 4, 6, 8, 12, 24, 48, 120, 240, 360, and 480 hours after MK-4334 administration

  • Plasma Steady State Apparent Half-Life (t1/2) of MK-4334

    Day 14: Pre-dose and 0.5, 1, 2, 3, 4, 6, 8, 12, 24, 48, 120, 240, 360, and 480 hours after MK-4334 administration

  • Plasma Steady State Time to Maximum Concentration (Tmax) of MK-4334

    Day 14: Pre-dose and 0.5, 1, 2, 3, 4, 6, 8, 12, 24, 48, 120, 240, 360, and 480 hours after MK-4334 administration

  • +2 more secondary outcomes

Study Arms (2)

Donepezil + MK-4334

EXPERIMENTAL

Oral MK-4334 60/120 mg QD and open-label, oral donepezil 10 mg QD.

Drug: MK-4334Drug: Donepepzil

Donepezil + Placebo

PLACEBO COMPARATOR

Placebo to MK-4334 QD and open-label, oral donepezil 10 mg QD.

Drug: Placebo to MK-4334Drug: Donepepzil

Interventions

Participants with Alzheimer's clinical syndrome (MCI or mild/moderate AD) will receive MK-4334 capsules administered orally, QD on Days 1-14. Participants will receive an initial loading dose of 120 mg (Day 1), followed by a maintenance dose of 60 mg (Days 2-14). Open-label donepezil tablets (dose strength: 10 mg) administered orally, QD on Days 1-14.

Also known as: Aricept
Donepezil + MK-4334

Participants with Alzheimer's clinical syndrome (MCI or mild/moderate AD)will receive placebo capsules matching MK-4334 administered orally, QD on Days 1-14. Participants will also receive open-label donepezil tablets (dose strength: 10 mg) administered orally, QD on Days 1-14.

Also known as: Aricept
Donepezil + Placebo

Participants with Alzheimer's clinical syndrome (MCI or mild/moderate AD) will receive open-label, oral donepezil 10 mg QD on Days 1-14.

Also known as: Aricept
Donepezil + MK-4334Donepezil + Placebo

Eligibility Criteria

Age55 Years - 85 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Participants with MCI
  • Have a history of subjective memory decline with gradual onset and slow progression for at least one year before screening.
  • Have general cognitive function and activities of daily living sufficiently intact, based on clinical assessment, so as not to meet criteria for mild AD dementia based on National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria.
  • Have a Mini Mental State Exam-2 (MMSE-2) score ≥24.
  • Have a Clinical Dementia Rating (CDR) scale score of 0.5, including a memory subscale score ≥ 0.5.
  • Participants with AD
  • Have a history of cognitive and functional decline with gradual onset and slow progression for at least one year before screening.
  • Meet the criteria for a diagnosis of probable AD based on NINCDS-ADRDA criteria.
  • Have a MMSE-2 score ≥ 12 to ≤ 24 at screening.
  • Have a CDR score of 1 to 2.
  • All Participants
  • Have a Rosen-Modified Hachinski score ≤ 4.
  • Be on a stable dose of donepezil 10 mg PO daily for symptomatic treatment of Alzheimer's clinical syndrome. The dose must be stable for ≥2 months prior to screening.
  • Be in good health based on medical history, physical examination, vital sign (VS) measurements and electrocardiograms (ECGs) performed prior to randomization.
  • Have a Body Mass Index (BMI) ≤ 35 kg/m\^2.
  • +3 more criteria

You may not qualify if:

  • Is at imminent risk of self-harm, based on clinical interview and responses on the Columbia-Suicide Severity Rating Scale (C-SSRS), or of harm to others in the opinion of the investigator.
  • Has a history of uncontrolled endocrine, gastrointestinal, cardiovascular, hematological, hepatic, immunological, renal, respiratory, genitourinary, or major neurological (including stroke and chronic seizures) abnormalities or diseases.
  • Has evidence of a clinically relevant or unstable psychiatric disorder, based on Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria, including schizophrenia or other psychotic disorder, bipolar disorder, or delirium, at the time of prestudy (screening) visit, or has a history of clinically significant psychiatric disorder of the last 5 years.
  • Has a history of cancer (malignancy), except for: 1.) adequately-treated nonmelanomatous skin carcinoma or carcinoma in situ of the cervix or; 2.) Other malignancies which have been successfully treated with appropriate follow up and therefore unlikely to recur for the duration of the study.
  • Participant has an estimated creatinine clearance (CrCl) ≤55 mL/min based on the Modification of Diet in Renal Disease (MDRD).
  • Has a history of significant multiple and/or severe allergies (e.g., food, drug, latex allergy), or has had an anaphylactic reaction or significant intolerability (i.e., systemic allergic reaction) to prescription or non-prescription drugs or food.
  • Is positive for hepatitis B surface antigen, hepatitis C antibodies or human immunodeficiency virus (HIV).
  • Had major surgery, donated or lost 1 unit of blood (approximately 500 mL) within 4 weeks prior to the prestudy (screening) visit.
  • Is unable to refrain from or anticipates the use of strong or moderate inhibitors or inducers of Cytochrome P450 (CYP) 3A4 (CYP3A4) and CYP2C19 beginning approximately 28 days prior to administration of the initial dose of study drug, throughout the study, and until the post-trial visit.
  • Has participated in another investigational study within 4 weeks (or 5 half-lives, whichever is greater) prior to the prestudy (screening) visit.
  • Has a rate-corrected QT (QTc) interval ≥470 msec (for males) or ≥480 msec (for females).
  • Is a smoker and/or has used nicotine or nicotine-containing products (e.g., nicotine patch and electronic cigarette) within 3 months of screening.
  • Consumes greater than 3 glasses of alcoholic beverages (1 glass is approximately equivalent to: beer \[354 mL/12 ounces\], wine \[118 mL/4 ounces\], or distilled spirits \[29.5 mL/1 ounce\]) per day.
  • Consumes excessive amounts, defined as greater than 6 servings of coffee, tea, cola, energy drinks, or other caffeinated beverages per day.
  • Is a regular user of cannabis, any illicit drugs or has a history of drug (including alcohol) abuse within approximately 2 years. Participants must have a negative urine drug screen prior to randomization.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

MeSH Terms

Conditions

Alzheimer DiseaseCognitive Dysfunction

Interventions

Donepezil

Condition Hierarchy (Ancestors)

DementiaBrain DiseasesCentral Nervous System DiseasesNervous System DiseasesTauopathiesNeurodegenerative DiseasesNeurocognitive DisordersMental DisordersCognition Disorders

Intervention Hierarchy (Ancestors)

IndansIndenesPolycyclic Aromatic HydrocarbonsHydrocarbons, AromaticHydrocarbons, CyclicHydrocarbonsOrganic ChemicalsPiperidinesHeterocyclic Compounds, 1-RingHeterocyclic CompoundsPolycyclic Compounds

Study Officials

  • Medical Director

    Merck Sharp & Dohme LLC

    STUDY DIRECTOR
0

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

November 12, 2018

First Posted

November 14, 2018

Study Start

September 27, 2019

Primary Completion

February 28, 2020

Study Completion

February 28, 2020

Last Updated

April 25, 2025

Record last verified: 2025-04

Data Sharing

IPD Sharing
Will share

https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf

More information