Trial Outcomes & Findings for Elpipodect (MK-8189) Safety and Tolerability in Participants With Alzheimer's Disease With or Without Symptoms of Agitation-Aggression and/or Psychosis (MK-8189-017) (NCT NCT05227118)

Last Updated: 2026-04-29

Results Overview

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. Results are reported according to dose.

Recruitment status

COMPLETED

Study phase

PHASE1

Target enrollment

29 participants

Primary outcome timeframe

Up to approximately 42 days

Results posted on

2026-04-29

Participant Flow

This study was conducted at 8 sites in the United States.

Participant milestones

Participant milestones
Measure	Titration 1: MK-8189 Participants received MK-8189 8 mg on Days 1 to 3 and MK-8189 16 mg on Days 4 to 28 during Titration 1.	Titration 1: Placebo Participants received placebo matched to MK-8189 during Titration 1.	Titration 2: MK-8189 Participants received MK-8189 8 mg on Days 1 to 3, 16 mg on Days 4 to 6, and 24 mg on Days 7 to 28 during Titration 2.	Titration 2: Placebo Participants received placebo matched to MK-8189 during Titration 2.
Overall Study STARTED	6	2	16	5
Overall Study COMPLETED	6	2	13	5
Overall Study NOT COMPLETED	0	0	3	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Titration 1: MK-8189 Participants received MK-8189 8 mg on Days 1 to 3 and MK-8189 16 mg on Days 4 to 28 during Titration 1.	Titration 1: Placebo Participants received placebo matched to MK-8189 during Titration 1.	Titration 2: MK-8189 Participants received MK-8189 8 mg on Days 1 to 3, 16 mg on Days 4 to 6, and 24 mg on Days 7 to 28 during Titration 2.	Titration 2: Placebo Participants received placebo matched to MK-8189 during Titration 2.
Overall Study Adverse Event	0	0	1	0
Overall Study Withdrawal by Subject	0	0	2	0

Baseline Characteristics

Elpipodect (MK-8189) Safety and Tolerability in Participants With Alzheimer's Disease With or Without Symptoms of Agitation-Aggression and/or Psychosis (MK-8189-017)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Titration 1: MK-8189 n=6 Participants Participants received MK-8189 8 mg on Days 1 to 3 and MK-8189 16 mg on Days 4 to 28 during Titration 1.	Titration 1: Placebo n=2 Participants Participants received placebo matched to MK-8189 during Titration 1.	Titration 2: MK-8189 n=16 Participants Participants received MK-8189 8 mg on Days 1 to 3, 16 mg on Days 4 to 6, and 24 mg on Days 7 to 28 during Titration 2.	Titration 2: Placebo n=5 Participants Participants received placebo matched to MK-8189 during Titration 2.	Total n=29 Participants Total of all reporting groups
Age, Continuous	73.0 years STANDARD_DEVIATION 4.0 • n=9 Participants	71.5 years STANDARD_DEVIATION 0.7 • n=24 Participants	71.6 years STANDARD_DEVIATION 7.6 • n=23 Participants	71.2 years STANDARD_DEVIATION 4.5 • n=73 Participants	71.7 years STANDARD_DEVIATION 4.7 • n=451 Participants
Sex: Female, Male Female	3 Participants n=9 Participants	2 Participants n=24 Participants	7 Participants n=23 Participants	3 Participants n=73 Participants	15 Participants n=451 Participants
Sex: Female, Male Male	3 Participants n=9 Participants	0 Participants n=24 Participants	9 Participants n=23 Participants	2 Participants n=73 Participants	14 Participants n=451 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	4 Participants n=9 Participants	2 Participants n=24 Participants	11 Participants n=23 Participants	5 Participants n=73 Participants	22 Participants n=451 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	2 Participants n=9 Participants	0 Participants n=24 Participants	5 Participants n=23 Participants	0 Participants n=73 Participants	7 Participants n=451 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=9 Participants	0 Participants n=24 Participants	0 Participants n=23 Participants	0 Participants n=73 Participants	0 Participants n=451 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=9 Participants	0 Participants n=24 Participants	0 Participants n=23 Participants	0 Participants n=73 Participants	0 Participants n=451 Participants
Race (NIH/OMB) Asian	0 Participants n=9 Participants	0 Participants n=24 Participants	0 Participants n=23 Participants	0 Participants n=73 Participants	0 Participants n=451 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=9 Participants	0 Participants n=24 Participants	0 Participants n=23 Participants	0 Participants n=73 Participants	0 Participants n=451 Participants
Race (NIH/OMB) Black or African American	2 Participants n=9 Participants	2 Participants n=24 Participants	5 Participants n=23 Participants	0 Participants n=73 Participants	9 Participants n=451 Participants
Race (NIH/OMB) White	4 Participants n=9 Participants	0 Participants n=24 Participants	11 Participants n=23 Participants	5 Participants n=73 Participants	20 Participants n=451 Participants
Race (NIH/OMB) More than one race	0 Participants n=9 Participants	0 Participants n=24 Participants	0 Participants n=23 Participants	0 Participants n=73 Participants	0 Participants n=451 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=9 Participants	0 Participants n=24 Participants	0 Participants n=23 Participants	0 Participants n=73 Participants	0 Participants n=451 Participants

PRIMARY outcome

Timeframe: Up to approximately 42 days

Population: All treated participants are included.

Outcome measures

Outcome measures
Measure	MK-8189 8 mg n=22 Participants Participants received MK-8189 8 mg on Days 1 to 3 during Titrations 1 and 2.	MK-8189 16 mg n=22 Participants Participants received MK-8189 16 mg on Days 4 to 28 during Titration 1, and on Days 4 to 6 during Titration 2.	MK-8189 24 mg n=14 Participants Participants received MK-8189 24 mg on Days 7 to 28 during Titration 2.	Placebo n=7 Participants Participants received placebo matched to MK-8189 during Titrations 1 and 2.
Number of Participants Who Experienced an Adverse Event (AE)	3 Participants	8 Participants	5 Participants	1 Participants

PRIMARY outcome

Timeframe: Up to approximately 42 days

Population: All treated participants are included.

Outcome measures

Outcome measures
Measure	MK-8189 8 mg n=22 Participants Participants received MK-8189 8 mg on Days 1 to 3 during Titrations 1 and 2.	MK-8189 16 mg n=22 Participants Participants received MK-8189 16 mg on Days 4 to 28 during Titration 1, and on Days 4 to 6 during Titration 2.	MK-8189 24 mg n=14 Participants Participants received MK-8189 24 mg on Days 7 to 28 during Titration 2.	Placebo n=7 Participants Participants received placebo matched to MK-8189 during Titrations 1 and 2.
Number of Participants Discontinuing From Study Therapy Due to AE	1 Participants	0 Participants	0 Participants	0 Participants

Adverse Events

MK-8189 8 mg

Serious events: 0 serious events

Other events: 3 other events

Deaths: 0 deaths

MK-8189 16 mg

Serious events: 1 serious events

Other events: 8 other events

Deaths: 0 deaths

MK-8189 24 mg

Serious events: 0 serious events

Other events: 5 other events

Deaths: 0 deaths

Placebo

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	MK-8189 8 mg n=22 participants at risk Participants received MK-8189 8 mg on Days 1 to 3 during Titrations 1 and 2.	MK-8189 16 mg n=22 participants at risk Participants received MK-8189 16 mg on Days 4 to 28 during Titration 1, and on Days 4 to 6 during Titration 2.	MK-8189 24 mg n=14 participants at risk Participants received MK-8189 24 mg on Days 7 to 28 during Titration 2.	Placebo n=7 participants at risk Participants received placebo matched to MK-8189 during Titrations 1 and 2.
Gastrointestinal disorders Intestinal obstruction	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Number of events 1 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Gastrointestinal disorders Intestinal pseudo-obstruction	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Number of events 1 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.

Other adverse events

Additional Information

Senior Vice President, Global Clinical Development

Merck Sharp & Dohme LLC

Phone: 1-800-672-6372

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee If publication activity is not directed by the Sponsor, the investigator agrees to submit all manuscripts or abstracts to the Sponsor before submission.
Publication restrictions are in place

Restriction type: OTHER

Measure	MK-8189 8 mg n=22 participants at risk Participants received MK-8189 8 mg on Days 1 to 3 during Titrations 1 and 2.	MK-8189 16 mg n=22 participants at risk Participants received MK-8189 16 mg on Days 4 to 28 during Titration 1, and on Days 4 to 6 during Titration 2.	MK-8189 24 mg n=14 participants at risk Participants received MK-8189 24 mg on Days 7 to 28 during Titration 2.	Placebo n=7 participants at risk Participants received placebo matched to MK-8189 during Titrations 1 and 2.
Psychiatric disorders Insomnia	0.00% 0/22 • Up to approximately 42 days All participants are included.	13.6% 3/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Renal and urinary disorders Micturition urgency	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/22 • Up to approximately 42 days All participants are included.	7.1% 1/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Injury, poisoning and procedural complications Contusion	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Injury, poisoning and procedural complications Fall	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/22 • Up to approximately 42 days All participants are included.	7.1% 1/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Cardiac disorders Palpitations	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Gastrointestinal disorders Diarrhoea	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	21.4% 3/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Gastrointestinal disorders Dyspepsia	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	7.1% 1/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Gastrointestinal disorders Nausea	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Gastrointestinal disorders Salivary hypersecretion	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Investigations Blood potassium increased	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Musculoskeletal and connective tissue disorders Costochondritis	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Musculoskeletal and connective tissue disorders Muscle spasms	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Musculoskeletal and connective tissue disorders Neck pain	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	14.3% 1/7 • Up to approximately 42 days All participants are included.
Nervous system disorders Dizziness	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Nervous system disorders Electric shock sensation	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Nervous system disorders Presyncope	0.00% 0/22 • Up to approximately 42 days All participants are included.	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.
Nervous system disorders Somnolence	4.5% 1/22 • Up to approximately 42 days All participants are included.	0.00% 0/22 • Up to approximately 42 days All participants are included.	0.00% 0/14 • Up to approximately 42 days All participants are included.	0.00% 0/7 • Up to approximately 42 days All participants are included.