SchizophreniaPhase 1NCT04506905
Safety, Tolerability, and Pharmacokinetics Study of Elpipodect (MK-8189) in Participants With Schizophrenia and Healthy Participants (MK-8189-011)
A Phase 1 study testing Elpipodect in people with Schizophrenia, run by Merck Sharp & Dohme LLC at 6 sites in United States.
Trial summary
This is a randomized, double-blind, 2-part clinical study of the safety, tolerability and pharmacokinetics of alternate elpipodect titration regimens. Part 1 assessed multiple dose once-daily titration regimens of elpipodect in young adult participants with schizophrenia. Read more about this study
- Who is it for?
- Ages 18 to 80 yearsHealthy volunteers can take part
- Conditions the study is for
- Schizophrenia
- What is being tested?
- Elpipodect
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 63 participants
- Where
- 6 sitesUnited States
- Study dates
- 28 Aug 2020to 22 Mar 2022
- Phase
- Phase 1
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Has a body mass index (BMI) ≤40 kg/m2
- Has no clinically significant abnormality on 12-lead safety electrocardiogram (ECG) performed at the prestudy (screening) visit and/or prior to randomization
- Has a normal resting blood pressure (BP: systolic BP is ≥90 millimeter of mercury [mmHg] and ≤140 mmHg; diastolic BP is ≥60 mmHg and ≤90 mmHg) and normal resting heart rate (≥45 beats per minute [bpm] and ≤100 bpm) in the semirecumbent position at the prestudy (screening) visit and/or prior to randomization. Repeat evaluations may be done if the values for a participant are, per investigator discretion, minimally outside the designated range. Participants may be included if values are outside the normal range but considered not clinically significant per investigator discretion
- Participants with schizophrenia only: Meets diagnostic criteria for schizophrenia or schizoaffective disorder according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria with the onset of the first episode being no less than 2 years prior to screening and monotherapy with antipsychotics for treatment should be indicated
- Participants with schizophrenia only: Has a total Brief Psychiatric Rating Scale (BPRS) score of <48 with a BPRS score <4 for #10 (hostility) and #14 (uncooperativeness) at the screening visit
- Participants with schizophrenia only: Is in the nonacute phase of their illness and clinically stable for 3 months prior to screening as demonstrated by the following: 1) no clinically significant change in dose of prescribed antipsychotic medication, or clinically significant change in antipsychotic medication to treat symptoms of schizophrenia for 2 months prior to screening 2) no increase in level of psychiatric care due to worsening of symptoms of schizophrenia for 3 months prior to screening
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- Participants with schizophrenia only: Has a history of receiving and tolerating antipsychotic medication within the usual dose range employed for schizophrenia
- Participants with schizophrenia only: Has a stable living situation
- Participants with hypothyroidism, diabetes, high BP, chronic respiratory conditions or other mild forms of these medical conditions could be considered as candidates for study enrollment if their condition is stable
- Has regular bowel movements
- Participants with schizophrenia only: Is able to discontinue the use of all antipsychotic medication at least 5 days prior to the start of the treatment period and during the study period
- Female participants are not pregnant and not breastfeeding, and are not a woman of childbearing potential (WOCBP) or are a WOCBP who agrees to follow contraceptive guidance during the treatment period and for at least 14 days after the last dose of study intervention
Who cannot join
- Is a WOCBP who has a positive urine pregnancy test within 48 hours before the first dose of study intervention
- Participants with schizophrenia only: Has evidence or history of a primary DSM-5 axis I psychiatric diagnosis other than schizophrenia or schizoaffective disorder per the allowed DSM-5 criteria within 1 month of screening
- Has evidence or history of a primary DSM-5 axis I psychiatric diagnosis other than schizophrenia or schizoaffective disorder per the allowed DSM-5 criteria within 1 month of screening
- Has evidence or history of mental retardation, borderline personality disorder, anxiety disorder, or organic brain syndrome
- Has a history of neuroleptic malignant syndrome or moderate to severe tardive dyskinesia
- Has a substance-induced psychotic disorder or behavioral disturbance thought to be due to substance abuse
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- Has a DSM-5 defined substance use disorder within 3 months of screening
- Has a history of seizure disorder beyond childhood or is receiving treatment with any anticonvulsant to prevent seizures
- Has an untreated or uncompensated clinically significant renal, endocrine, hepatic, respiratory, gastrointestinal, psychiatric, neurologic, cardiovascular, hematological, immunological or cerebrovascular disease, malignancy, allergic disease or other chronic and/or degenerative process at screening
- Has any clinically significant abnormal laboratory, vital sign (VS), physical examination, or 12-lead safety ECG findings at screening or changes from baseline parameters or, in the opinion of the investigator, would make the participant inappropriate for entry into this study
- Has a history of cancer with following exceptions: 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, in the opinion of the investigator and with agreement of the Sponsor
- Has a clinically significant history or presence of sick sinus syndrome, first, second, or third-degree AV block, myocardial infarction, pulmonary congestion, cardiac arrhythmia, prolonged corrected QT (QTc) interval, or conduction abnormalities
- Has history of repeated or frequent syncope, vasovagal episodes, or epileptic seizures
- Has a family history of sudden death
- Has a history of any illness that, in the opinion of the study investigator, might confound the results of the study or poses an additional risk to the participant by their participation in the study
- For Part 2 participants only: Participant has an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 based on the modification of diet in renal disease (MDRD). Participants who have an eGFR or measured creatinine clearance of up to10% below of either 60 milliliter/minute [mL/min] (for creatinine clearance) or 60 mL/min/1.73m2 (for eGFR) may be enrolled in the study at the discretion of the investigator
- Has a history of significant multiple and/or severe allergies or has had an anaphylactic reaction or significant intolerability to prescription or non-prescription drugs or food
- Is positive for Hepatitis B surface antigen, Hepatitis C antibodies or HIV
- Had major surgery, donated or lost 1 unit of blood within 4 weeks prior to the prestudy (screening) visit
- Healthy participants only: Is 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 investigator's discretion)
- Participants with schizophrenia only: 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
- Healthy participants only: Is at imminent risk of self-harm, based on clinical interview and responses on the CSSRS, or of harm to others in the opinion of the investigator. Participants must be excluded if they report suicidal ideation with intent, with or without a plan or in the past 5 years or suicidal behavior in their lifetime
- Has received treatment with clozapine for schizophrenia or treatment with monoamine oxidase inhibitors within 3 months of screening or cariprazine within 2 months of screening
- Has received a parenteral depot antipsychotic medication within 3 months of screening
- Is unable to refrain from the use of co-medication with a moderate or strong inhibiting or inducing effect on cytochrome (CYP3A) and/or cytochrome (CYP2C9) beginning approximately 2 weeks or 5 half-lives, whichever is longer, prior to administration of the initial dose of trial drug and throughout the trial or is unable to refrain from the use of sensitive substrates of cytochrome (CYP2B6)
- Has participated in another investigational study within 4 weeks (or 5 half-lives, whichever is greater) prior to the prestudy (screening) visit
- Has been in incarceration or imprisonment within three months prior to screening
- Is a current smoker (healthy participants only) or is a smoker (participants with schizophrenia only) that does not agree to follow the smoking restrictions as defined by the clinical research unit (CRU)
- Consumes greater than 3 glasses of alcoholic beverages per day. Participants who consume 4 glasses of alcoholic beverages per day may be enrolled at the discretion of the investigator
- Consumes excessive amounts, defined as greater than 6 servings of caffeinated beverages per day
- Is a regular user of cannabis, any illicit drugs or has a history of drug abuse within approximately 3 years
- Presents any concern by the investigator regarding safe participation in the study or for any other reason the investigator considers the participant inappropriate for participation in the study
- Is or has an immediate family member who is investigational site or Sponsor staff directly involved with this study
Trial locations and contacts
6 sites in 1 country.
6 sites in 1 country
United States6 sites
Hassman Research Institute ( Site 0007)
Berlin, New Jersey, 08009
Parexel ( Site 0004)
Glendale, California, 91206
Velocity Clinical Research, Hallandale Beach ( Site 0001)
Hallandale, Florida, 33009
Collaborative NeuroScience Network ( Site 0008)
Long Beach, California, 90806
RCA at Fort Lauderdale Behavioral Health Center ( Site 0006)
Oakland Park, Florida, 33334
Woodland Research Northwest, LLC ( Site 0002)
Rogers, Arkansas, 72758-6442
About this study
Official title: A 2-Part Randomized Clinical Study to Evaluate the Safety, Tolerability and Pharmacokinetics of Alternate MK-8189 Titration Regimens in Young Adult Participants With Schizophrenia and to Evaluate the Safety, Tolerability and Pharmacokinetics of MK-8189 in Elderly Participants With Schizophrenia and Healthy Elderly
This is a randomized, double-blind, 2-part clinical study of the safety, tolerability and pharmacokinetics of alternate elpipodect titration regimens. Part 1 assessed multiple dose once-daily titration regimens of elpipodect in young adult participants with schizophrenia. Part 2 assessed multiple once-daily doses of elpipodect in elderly participants with schizophrenia and healthy elderly participants.
- Conditions
- Schizophrenia
- Being tested
- Elpipodect, Placebo
- Medical subject headings
- Schizophrenia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ElpipodectDrug
Also called MK-8189
MK-8189, oral, 4 mg and/or 12 mg tablets for a total daily dose of 8, 16 or 24 mg QD according to randomization
PlaceboDrug
Oral tablets of dose-matched placebo to MK-8189 according to randomization
| Study group | Role | What they receive |
|---|---|---|
| Part 1 (Panel A) Elpipodect | Experimental | Young adult participants with schizophrenia receive elpipodect titrated from 16 mg to 24 mg once daily (QD), orally, over a course of 7-day treatment. Receives: Drug: Elpipodect |
| Part 1 (Panel B) Elpipodect | Experimental | Young adult participants with schizophrenia receive elpipodect titrated up to 24 mg QD, orally, over a course of 7-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panel. Receives: Drug: Elpipodect |
| Part 1 (Panel C) Elpipodect | Experimental | Young adult participants with schizophrenia receive elpipodect titrated from 8 mg to 24 mg QD, orally, over a course of 7-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. Receives: Drug: Elpipodect |
| Part 2 (Panel D) Elpipodect | Experimental | Elderly adult participants with schizophrenia receive elpipodect titrated from 8 mg to 24 mg QD, orally, over the course of a 13-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. Receives: Drug: Elpipodect |
| Part 2 (Panel E) Elpipodect | Experimental | Elderly adult participants with schizophrenia receive elpipodect titrated from 16 mg to 24 mg QD, orally, over the course of 10-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. Receives: Drug: Elpipodect |
| Part 2 (Panel F) Elpipodect | Experimental | Healthy elderly adult participants receive elpipodect titrated from 8 mg to 24 mg QD, orally, over the course of a 13-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. Receives: Drug: Elpipodect |
| Part 2 (Panel G) Elpipodect | Experimental | Healthy elderly adult participants receive elpipodect titrated from 16 mg to 24 mg QD, orally, over the course of 10-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. Receives: Drug: Elpipodect |
| Part 1 (Panels A, B, C) Placebo | Placebo comparator | Oral tablets of dose-matched placebo to total daily dose of elpipodect. Receives: Drug: Placebo |
| Part 2 (Panels D, E, F, G) Placebo | Placebo comparator | Oral tablets of dose-matched placebo to total daily dose of elpipodect. Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Part 1 & 2: Number of Participants Who Experienced an Adverse Event (AE)
The number of participants with ≥1 AE is reported. 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.
Measured: Up to approximately 27 days
Part 1 & 2: Number of Participants Discontinuing Study Treatment Due to an AE
The number of participants discontinuing from study treatment due to ≥1 AE is reported. 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.
Measured: Up to approximately 27 days
Secondary outcomes (14)
Part 1: Area Under the Concentration Time-curve From Hour 0 to 24 Hours Postdose (AUC0-24) of MK-8189
AUC0-24 was determined for participants in Part 1 panels who received MK-8189.
Measured: Days 1, 2, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Concentration 24 Hours Postdose (C24) of MK-8189
C24 was determined for participants in Part 1 panels who received MK-8189.
Measured: Days 1, 2, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Maximum Plasma Concentration (Cmax) of MK-8189
Cmax was determined for participants in Part 1 panels who received MK-8189.
Measured: Days 1, 2, 3, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Time to Maximum Concentration (Tmax) of MK-8189
Tmax was determined for participants in Part 1 panels who received MK-8189.
Measured: Days 1, 2, 3, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Clearance (CL/F) of MK-8189
CL/F was determined for participants in Part 1 panels who received MK-8189.
Measured: Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Apparent Terminal Half-life (t½) of MK-8189
t½ was determined for participants in Part 1 panels who received MK-8189.
Measured: Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Volume of Distribution (Vd/F) of MK-8189
Vd/F was determined for participants in Part 1 panels who received MK-8189.
Measured: Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: AUC0-24 of MK-8189
AUC0-24 was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: C24 of MK-8189
C24 was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: Cmax of MK-8189
Cmax was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: Tmax of MK-8189
Tmax was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: CL/F of MK-8189
CL/F was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 10 and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: t½ of MK-8189
t½ was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 10 and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: Vd/F of MK-8189
Vd/F was determined for participants in Part 2 panels who received MK-8189.
Measured: Days 10 and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Aug 2020
- Study start28 Aug 2020
- Primary completion22 Mar 2022
- Study completion22 Mar 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for SchizophreniaStudies of the same condition, open and under way.
- More trials run by Merck Sharp & Dohme LLCThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 63 participants (actual)
Sponsor and investigators
- Lead sponsor
- Merck Sharp & Dohme LLC
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Medical Director, Study director, Merck Sharp & Dohme LLC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04506905
- Sponsor's protocol ID
- 8189-011
- Other IDs
- Merck Protocol Number
- Status last verified
- Apr 2026
- First submitted
- 6 Aug 2020
- Last updated
- 29 Apr 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Study at a glance
From the registry record, last updated by the sponsor on 29 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A 2-Part Randomized Clinical Study to Evaluate the Safety, Tolerability and Pharmacokinetics of Alternate MK-8189 Titration Regimens in Young Adult Participants With Schizophrenia and to Evaluate the Safety, Tolerability and Pharmacokinetics of MK-8189 in Elderly Participants With Schizophrenia and Healthy Elderly
- ClinicalTrials.gov ID
- NCT04506905
- Acronym / sponsor ID
- 8189-011
- Conditions
- Schizophrenia
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 63 participants (actual)
- Lead sponsor
- Merck Sharp & Dohme LLCIndustry (pharma, biotech, devices)
- Study start
- 28 Aug 2020 (actual)
- Primary completion
- 22 Mar 2022 (actual)
- Study completion
- 22 Mar 2022 (actual)
- First posted
- 10 Aug 2020 (actual)
- Results
- Posted 2 Oct 2024
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a randomized, double-blind, 2-part clinical study of the safety, tolerability and pharmacokinetics of alternate elpipodect titration regimens. Part 1 assessed multiple dose once-daily titration regimens of elpipodect in young adult participants with schizophrenia. Part 2 assessed multiple once-daily doses of elpipodect in elderly participants with schizophrenia and healthy elderly participants.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 9
| Arm | Type | Receives |
|---|---|---|
| Part 1 (Panel A) Elpipodect | Experimental | Drug: ElpipodectYoung adult participants with schizophrenia receive elpipodect titrated from 16 mg to 24 mg once daily (QD), orally, over a course of 7-day treatment. |
| Part 1 (Panel B) Elpipodect | Experimental | Drug: ElpipodectYoung adult participants with schizophrenia receive elpipodect titrated up to 24 mg QD, orally, over a course of 7-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panel. |
| Part 1 (Panel C) Elpipodect | Experimental | Drug: ElpipodectYoung adult participants with schizophrenia receive elpipodect titrated from 8 mg to 24 mg QD, orally, over a course of 7-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. |
| Part 2 (Panel D) Elpipodect | Experimental | Drug: ElpipodectElderly adult participants with schizophrenia receive elpipodect titrated from 8 mg to 24 mg QD, orally, over the course of a 13-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. |
| Part 2 (Panel E) Elpipodect | Experimental | Drug: ElpipodectElderly adult participants with schizophrenia receive elpipodect titrated from 16 mg to 24 mg QD, orally, over the course of 10-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. |
| Part 2 (Panel F) Elpipodect | Experimental | Drug: ElpipodectHealthy elderly adult participants receive elpipodect titrated from 8 mg to 24 mg QD, orally, over the course of a 13-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. |
| Part 2 (Panel G) Elpipodect | Experimental | Drug: ElpipodectHealthy elderly adult participants receive elpipodect titrated from 16 mg to 24 mg QD, orally, over the course of 10-day treatment period with starting doses based on safety and tolerability of previous starting dose in previous panels. |
| Part 1 (Panels A, B, C) Placebo | Placebo comparator | Drug: PlaceboOral tablets of dose-matched placebo to total daily dose of elpipodect. |
| Part 2 (Panels D, E, F, G) Placebo | Placebo comparator | Drug: PlaceboOral tablets of dose-matched placebo to total daily dose of elpipodect. |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (12 listed)
- Has a body mass index (BMI) ≤40 kg/m2
- Has no clinically significant abnormality on 12-lead safety electrocardiogram (ECG) performed at the prestudy (screening) visit and/or prior to randomization
- Has a normal resting blood pressure (BP: systolic BP is ≥90 millimeter of mercury [mmHg] and ≤140 mmHg; diastolic BP is ≥60 mmHg and ≤90 mmHg) and normal resting heart rate (≥45 beats per minute [bpm] and ≤100 bpm) in the semirecumbent position at the prestudy (screening) visit and/or prior to randomization. Repeat evaluations may be done if the values for a participant are, per investigator discretion, minimally outside the designated range. Participants may be included if values are outside the normal range but considered not clinically significant per investigator discretion
- Participants with schizophrenia only: Meets diagnostic criteria for schizophrenia or schizoaffective disorder according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria with the onset of the first episode being no less than 2 years prior to screening and monotherapy with antipsychotics for treatment should be indicated
- Participants with schizophrenia only: Has a total Brief Psychiatric Rating Scale (BPRS) score of <48 with a BPRS score <4 for #10 (hostility) and #14 (uncooperativeness) at the screening visit
Key exclusion criteria (33 listed)
- Is a WOCBP who has a positive urine pregnancy test within 48 hours before the first dose of study intervention
- Participants with schizophrenia only: Has evidence or history of a primary DSM-5 axis I psychiatric diagnosis other than schizophrenia or schizoaffective disorder per the allowed DSM-5 criteria within 1 month of screening
- Has evidence or history of a primary DSM-5 axis I psychiatric diagnosis other than schizophrenia or schizoaffective disorder per the allowed DSM-5 criteria within 1 month of screening
- Has evidence or history of mental retardation, borderline personality disorder, anxiety disorder, or organic brain syndrome
- Has a history of neuroleptic malignant syndrome or moderate to severe tardive dyskinesia
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ElpipodectAlso: MK-8189MK-8189, oral, 4 mg and/or 12 mg tablets for a total daily dose of 8, 16 or 24 mg QD according to randomization | Drug | Part 1 (Panel A) Elpipodect, Part 1 (Panel B) Elpipodect, Part 1 (Panel C) Elpipodect, Part 2 (Panel D) Elpipodect, Part 2 (Panel E) Elpipodect, Part 2 (Panel F) Elpipodect, Part 2 (Panel G) Elpipodect |
| PlaceboOral tablets of dose-matched placebo to MK-8189 according to randomization | Drug | Part 1 (Panels A, B, C) Placebo, Part 2 (Panels D, E, F, G) Placebo |
Primary outcome
Part 1 & 2: Number of Participants Who Experienced an Adverse Event (AE)
Time frame: Up to approximately 27 days
The number of participants with ≥1 AE is reported. 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.
Part 1 & 2: Number of Participants Discontinuing Study Treatment Due to an AE
Time frame: Up to approximately 27 days
The number of participants discontinuing from study treatment due to ≥1 AE is reported. 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.
14 secondary outcomes
Part 1: Area Under the Concentration Time-curve From Hour 0 to 24 Hours Postdose (AUC0-24) of MK-8189
Time frame: Days 1, 2, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Concentration 24 Hours Postdose (C24) of MK-8189
Time frame: Days 1, 2, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Maximum Plasma Concentration (Cmax) of MK-8189
Time frame: Days 1, 2, 3, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Time to Maximum Concentration (Tmax) of MK-8189
Time frame: Days 1, 2, 3, 4, and Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Clearance (CL/F) of MK-8189
Time frame: Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Apparent Terminal Half-life (t½) of MK-8189
Time frame: Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 1: Volume of Distribution (Vd/F) of MK-8189
Time frame: Day 7: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: AUC0-24 of MK-8189
Time frame: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: C24 of MK-8189
Time frame: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: Cmax of MK-8189
Time frame: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: Tmax of MK-8189
Time frame: Days 1, 4, 7, 10, and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: CL/F of MK-8189
Time frame: Days 10 and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: t½ of MK-8189
Time frame: Days 10 and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Part 2: Vd/F of MK-8189
Time frame: Days 10 and 13: Predose and 2, 6, 8, 10, 12, 16, and 24 hours postdose
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Apr 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Merck Clinical Trials InformationLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Medical Director study director
Merck Sharp & Dohme LLC
6 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Elpipodect in people with Schizophrenia, run by Merck Sharp & Dohme LLC at 6 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 12 inclusion and 33 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 29 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 2 Oct 2024). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Part 1 & 2: Number of Participants Who Experienced an Adverse Event (AE) (time frame: Up to approximately 27 days). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Apr 2026.