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NCT05406440

A Study of MK-8189 in Participants With Schizophrenia (MK-8189-014)

Completed Phase 1 Results posted Last updated 25 July 2024
What this trial tests

Phase 1 trial testing MK-8189 in Schizophrenia in 53 participants. Completed in 24 February 2023.

Timeline
12 July 2022
Primary endpoint
24 February 2023
24 February 2023

Quick facts

Lead sponsorMerck Sharp & Dohme LLC
PhasePhase 1
StatusCompleted
Study typeINTERVENTIONAL
Allocationrandomized
Designparallel
Maskingdouble
Primary purposetreatment
Enrollment53
Start date12 July 2022
Primary completion24 February 2023
Estimated completion24 February 2023
Sites3 locations across United States

Drugs / interventions tested

Conditions studied

Sponsor

Merck Sharp & Dohme LLC — full company profile →

Who can join

Adults 18 to 55, any sex, with Schizophrenia. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Number of Participants Experiencing an Adverse Event (AE) Primary · Up to approximately 17 days

An AE is any untoward medical occurrence in a clinical study participant, temporarily associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who experienced one or more AEs were reported.

GroupValue95% CI
Panel A MK-8189 48 mg3
Panel A MK-8189 60mg2
Panel A Placebo0
Panel A-1 MK-8189 48 mg3
Panel A-1 MK-8189 80 mg4
Panel A-1 Placebo0
Panel C MK-8189 48 mg7
Panel C MK-8189 80 mg6
Panel C Placebo6
Number of Participants Who Discontinue From Study Treatment Due to an AE Primary · Up to approximately 3 days

An AE is any untoward medical occurrence in a clinical study participant, temporarily associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who discontinued study due to an AE were reported.

GroupValue95% CI
Panel A MK-8189 48 mg0
Panel A MK-8189 60mg0
Panel A Placebo0
Panel A-1 MK-8189 48 mg0
Panel A-1 MK-8189 80 mg0
Panel A-1 Placebo0
Panel C MK-8189 48 mg1
Panel C MK-8189 80 mg0
Panel C Placebo0

Adverse events — posted to ClinicalTrials.gov

Time frame: Up to approximately 17 days. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Panel A MK-8189 Dose 48 mg
Serious: 0/8 (0%)
Deaths: 0/8
Panel A MK-8189 60mg
Serious: 0/8 (0%)
Deaths: 0/8
Panel A Placebo
Serious: 0/3 (0%)
Deaths: 0/3
Panel A-1 MK-8189 48 mg
Serious: 0/8 (0%)
Deaths: 0/8
Panel A-1 MK-8189 80 mg
Serious: 0/8 (0%)
Deaths: 0/8
Panel A-1 Placebo
Serious: 0/2 (0%)
Deaths: 0/2
Panel C MK-8189 48 mg
Serious: 0/20 (0%)
Deaths: 0/20
Panel C MK-8189 80 mg
Serious: 0/18 (0%)
Deaths: 0/20
Panel C Placebo
Serious: 0/12 (0%)
Deaths: 0/12
Other adverse events (33 terms — click to expand)

ReactionSystemPanel A MK-8189 Dose 48 mgPanel A MK-8189 60mgPanel A PlaceboPanel A-1 MK-8189 48 mgPanel A-1 MK-8189 80 mgPanel A-1 PlaceboPanel C MK-8189 48 mgPanel C MK-8189 80 mgPanel C Placebo
HeadacheNervous system disorders
SomnolenceNervous system disorders
DizzinessNervous system disorders
MiosisEye disorders
ConstipationGastrointestinal disorders
Dry mouthGastrointestinal disorders
NauseaGastrointestinal disorders
VomitingGastrointestinal disorders
AstheniaGeneral disorders
DiscomfortGeneral disorders
FatigueGeneral disorders
Feeling jitteryGeneral disorders
Liver function test increasedInvestigations
Decreased appetiteMetabolism and nutrition disorders
HypokalaemiaMetabolism and nutrition disorders
Increased appetiteMetabolism and nutrition disorders
Back painMusculoskeletal and connective tissue disorders
Muscle twitchingMusculoskeletal and connective tissue disorders
Pain in extremityMusculoskeletal and connective tissue disorders
AkathisiaNervous system disorders
DystoniaNervous system disorders
NystagmusNervous system disorders
Oromandibular dystoniaNervous system disorders
ParosmiaNervous system disorders
TremorNervous system disorders
AgitationPsychiatric disorders
AnxietyPsychiatric disorders
InsomniaPsychiatric disorders
RestlessnessPsychiatric disorders
Vulvovaginal discomfortReproductive system and breast disorders
Dermatitis contactSkin and subcutaneous tissue disorders
Skin irritationSkin and subcutaneous tissue disorders
Substance useSocial circumstances

Data from ClinicalTrials.gov NCT05406440 adverse events section.

Sponsor's own description

The primary purpose of this study is to assess the safety and tolerability of multiple ascending doses of MK-8189 in participants with schizophrenia.

Publications & conference data

4 peer-reviewed publications reference this trial (live from Europe PMC):

  1. Recent developments of phosphodiesterase inhibitors: Clinical trials, emerging indications and novel molecules.
    Bondarev AD, Attwood MM, Jonsson J, Chubarev VN, et al · · 2022 · cited 52× · PMID 36506513 · DOI 10.3389/fphar.2022.1057083
  2. Overview of Novel Antipsychotic Drugs: State of the Art, New Mechanisms, and Clinical Aspects of Promising Compounds.
    Biso L, Carli M, Scarselli M, Longoni B. · · 2025 · cited 8× · PMID 39857669 · DOI 10.3390/biomedicines13010085
  3. Schizophrenia: Genetics, neurological mechanisms, and therapeutic approaches.
    Lim DXE, Yeo SY, Chia ZYA, Fernandis AZ, et al · · 2026 · cited 3× · PMID 40364647 · DOI 10.4103/nrr.nrr-d-24-01375
  4. PDE1B and PDE10A as novel targets for schizophrenia: from molecular design and synthesis to therapeutic promise.
    Rautela J, Gaurav A, Nissapatorn V, Tan CK, et al · · 2025 · PMID 41835457 · DOI 10.3389/fphar.2025.1735760

Verify or expand the search:

Other trials of MK-8189

Trials testing the same drug.

Other recruiting trials for Schizophrenia

Currently open trials in the same condition.

Other Merck Sharp & Dohme LLC trials

Trials by the same sponsor.

Verify against primary sources

Data sources for this page

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Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing