Efficacy and Safety of MK-8189 in Participants With an Acute Episode of Schizophrenia (MK-8189-008)

  • End date
    Oct 10, 2022
  • participants needed
  • sponsor
    Merck Sharp & Dohme Corp.
Updated on 23 September 2021
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Primary Contact
Alexian Center for Psychiatric Research ( Site 1000) (7.6 mi away) Contact
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The purpose of this study is to evaluate the efficacy and safety of MK-8189 at a range of doses (8 mg, 16 mg, and 24 mg once daily) in adult participants who have an acute episode of schizophrenia according to Diagnostic and Statistical Manual of Mental Disorders 5th Edition (DSM-5) criteria. The primary hypotheses are the following: (1) MK-8189 24 mg is superior to placebo in reducing the Week 6 mean change from baseline in Positive and Negative Syndrome Scale (PANSS) total score (2) MK-8189 16 mg is superior to placebo in reducing the Week 6 mean change from baseline in PANSS total score

Condition Schizophrenia, Schizophrenia and Schizoaffective Disorders, Schizophrenia and Schizoaffective Disorders (Pediatric), schizophrenia disorders
Treatment risperidone, MK-8189, Placebo to MK-8189, Placebo to risperidone
Clinical Study IdentifierNCT04624243
SponsorMerck Sharp & Dohme Corp.
Last Modified on23 September 2021


Yes No Not Sure

Inclusion Criteria

The main inclusion criteria include, but are not limited to the following
Meet the diagnostic criteria for schizophrenia according to the DSM-5
Have an illness duration for schizophrenia of at least 1 year and 15 years
Be confirmed to be experiencing an acute episode of schizophrenia as evidenced by ALL of the following: (a) onset of the current acute episode is 4 weeks prior to screening (b) current symptoms represent a marked and substantial worsening compared with the participant's usual symptomatic state prior to the current acute episode, and are associated with diminished functional ability (c) in need of increased psychiatric attention to treat worsening acute episode symptoms
Have a CGI-S score of 4 (moderately ill) at screening and baseline
Have an identified responsible person referred to as the "external contact person" who has agreed to provide information about the participant's location if needed during outpatient portion of the study. The site personnel must consider this identified responsible person a reliable contact person, and the contact person must have regular contact with the participant (defined at screening as direct contact no fewer than 3 times per week), and with the expectation that this frequency of contact would continue (either in person or via other contact method), throughout duration of the study, including the follow-up period)

Exclusion Criteria

The main exclusion criteria include, but are not limited to the following
Has a primary current diagnosis other than schizophrenia or a comorbid diagnosis that is primarily responsible for the current symptoms and functional impairment
Meets criteria for moderate to severe substance use disorder within past 6 months prior to screening (excluding those related to caffeine or nicotine)
Has a known history of the following: (a) borderline personality disorder, anti-social personality disorder, or bipolar disorder (b) traumatic brain injury causing ongoing cognitive difficulties, Alzheimer's disease, or another form of dementia, or any chronic organic disease of the central nervous system (c) intellectual disability of a severity that would impact ability to participate in the study
Has a current diagnosis of a psychotic disorder other than schizophrenia or a behavioral disturbance thought to be due to substance abuse
Is or was under involuntary commitment for the acute episode, because the participant is considered a danger to themselves or others
Has a history of treatment resistance exhibited by any of the following: (a) no or minimal response to at least 2 periods of treatment lasting 6 weeks or longer, with antipsychotic agents at the maximally tolerated dose. Participants who have responded to antipsychotics only when paired with clozapine are considered treatment resistant (b) history of electroconvulsive therapy (ECT) treatment for treatment resistant schizophrenia within the past 5 years (c) past or current use of clozapine as single or adjunctive therapy for schizophrenia within the past 5 years
Is currently participating in or has participated in an interventional clinical research study within 12 months prior to the screening visit of this current study
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