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NCT Number: NCT00827918

A Study to Test the Safety and Efficacy of MK-8998 in Acutely Psychotic Participants With Schizophrenia (MK-8998-004)

A study to evaluate the safety and efficacy of treatment with MK-8998 as compared to placebo and olanzapine for acutely psychotic patients with schizophrenia. The primary hypothesis is that in participants undergoing an acute psychotic episode of schizophrenia, MK-8998 6 to 8 mg twice daily is superior to placebo in the treatment of symptoms of schizophrenia as measured by the mean change from baseline in the Positive and Negative Syndrome Scale (PANSS) total score at Week 4.

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Key information

Conditions

Schizophrenia Mental Disorders Schizophrenia Spectrum and Other Psychotic Disorders

Age range

18 year–55 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patient's age is 18 to 55
  • Patient meets DSM-IV/DSM-IV-TR criteria for a primary diagnosis of schizophrenia
  • The duration of the patients schizophrenia diagnosis must be greater than 1 year
  • Patient has an acute exacerbation of psychotic symptoms (of at least 3 days but no longer than 6 weeks) and marked deterioration of function

Exclusion criteria

  • Patient currently has a clinically significant neurological, metabolic, hepatic, renal, hematological, pulmonary, cardiovascular, gastrointestinal, and/or urological disorder that would pose a risk to the patient in the opinion of the investigator if they were to participate in the study or that might confound the results of the study
  • The patient has evidence of acute hepatitis, clinically significant chronic hepatitis, or impaired hepatic function
  • The patient has a chronic organic disease of the central nervous system (other than schizophrenia) such as, tumors, inflammation, active seizure disorder, vascular disorder, Parkinson's disease, Alzheimer's disease or other forms of dementia, myasthenia gravis, or other degenerative processes. In addition, patients must not have a history of mental retardation or persistent neurological symptoms attributable to serious head injury
  • Patient has a history of alcohol/drug dependence within 3 months or alcohol/drug abuse within 1 month of screening. Exceptions include caffeine and nicotine abuse/dependence
  • Patient has a history of hypersensitivity to olanzapine OR poor response to olanzapine in the last 2 years OR intolerable side effects due to olanzapine OR patients current psychotic relapse occurred while consistently taking a therapeutic dose (10 mg or more) of olanzapine OR olanzapine is medically contradicted
  • Patient is refractory to antipsychotic treatment

Treatment and study plan

MK-8998

Drug

MK-8998 6 mg capsules twice daily with food on Days 1 through 7. On Day 8, dosage will be increased to 8 mg capsules twice daily. Treatment period is 4 weeks. There will be a period of time when all participants will receive placebo.

Comparator: Olanzapine

Drug

Olanzapine 5 mg tablets twice daily with food on Days 1 through 7. On Day 8, dosage will be increased to 5 mg tablets in the morning and 10 mg tablets in the evening. Treatment period is 4 weeks. There will be a period of time when all participants will receive placebo.

Comparator: placebo

Drug

Placebo tablets matching olanzapine tablets and MK-8998 capsules

Primary outcomes

  1. Mean Change From Baseline in the Positive and Negative Syndrome Scale (PANSS) at Week 4

    Time frame: Baseline and Week 4

    PANSS is a medical scale used for measuring symptom severity of participants with schizophrenia. PANSS measure is composed of 3 scales: Positive scale, Negative scale, and General Psychopathology scale. Positive scale assesses hallucinations, delusions and related symptoms; Negative scale assesses emotional withdrawal, lack of motivation, and similar symptoms; and General Psychopathology scale addresses other symptoms such as anxiety, somatic concern and disorientation. The PANSS has 30 items in its 3 scales and an anchored Likert scale from 1 to 7 is used to score each item. Values of 2 and above indicate the presence of progressively more severe symptoms. The Positive scale has 7 items with a score from 7 to 49, the Negative scale has 7 items with a score from 7 to 49, and the General Psychopathology scale has 16 items with a score from 16 to 112. A total score is the sum of the 3 scores for the 3 scales.

  2. Number of Participants Who Experienced at Least One Adverse Event

    Time frame: Up to 6 Weeks

    An adverse event (AE) is any unfavorable and unintended change in the structure, function or chemistry of the body temporally associated with study drug administration whether or not considered related to the use of the study drug.

  3. Number of Participants Who Discontinued Study Drug Due to an Adverse Event

    Time frame: Up to 4 Weeks

    An AE is any unfavorable and unintended change in the structure, function or chemistry of the body temporally associated with study drug administration whether or not considered related to the use of the study drug.

Secondary outcomes

  1. Percentage of Participants With Response at Week 4

    Time frame: Week 4

    Responders were defined as participants who demonstrated ≥ 20% improvement from baseline on the PANSS total score. PANSS measure is composed of 3 scales: Positive scale, Negative scale, and General Psychopathology scale. Positive scale assesses hallucinations, delusions and related symptoms; Negative scale assesses emotional withdrawal, lack of motivation, and similar symptoms; and General Psychopathology scale addresses other symptoms such as anxiety, somatic concern and disorientation. The PANSS has 30 items in its 3 scales and an anchored Likert scale from 1 to 7 is used to score each item. Values of 2 and above indicate the presence of progressively more severe symptoms. The Positive scale has 7 items with a score from 7 to 49, the Negative scale has 7 items with a score from 7 to 49, and the General Psychopathology scale has 16 items with a score from 16 to 112. A total score is the sum of the 3 scores for the 3 scales.

  2. Mean Change From Baseline in Clinical Global Impression - Severity of Illness Scale (CGI-S) at Week 4

    Time frame: Baseline and Week 4

    CGI-S is a commonly used measure of symptom severity in treatment studies of participants with mental disorders. CGI-S is a 7-point scale that requires the clinician to rate the severity of the participant's illness at the time of assessment, relative to the clinician's past experience with participants who have the same diagnosis. Considering total clinical experience, a participant is assessed on severity of mental illness at the time of rating 1 = normal, not at all ill; 2 = borderline mentally ill; 3 = mildly ill; 4 = moderately ill; 5 = markedly ill; 6 = severely ill; or 7 = extremely ill.

  3. Mean Change From Baseline in PANSS Positive Subscale at Week 4

    Time frame: Baseline and Week 4

    PANSS Positive scale assesses hallucinations, delusions and related symptoms. The Positive scale has 7 items with an anchored Likert scale from 1 to 7 to score each item. Values of 2 and above indicate the presence of progressively more severe symptoms. A total score ranges from 7 to 49.

  4. Mean Change From Baseline in PANSS Negative Subscale at Week 4

    Time frame: Baseline and Week 4

    PANSS Negative scale assesses emotional withdrawal, lack of motivation, and similar symptoms. The Negative scale has 7 items with an anchored Likert scale from 1 to 7 to score each item. Values of 2 and above indicate the presence of progressively more severe symptoms. A total score ranges from 7 to 49.

Sponsors and collaborators

Lead sponsor

Merck Sharp & Dohme LLC

Industry

Registry information

Official study title

A Phase IIa, Randomized, Multicenter, Double-Blind, Active Comparator- and Placebo-Controlled, Clinical Trial to Study the Safety and Efficacy of MK8998 in Acutely Psychotic Patients With Schizophrenia

Important dates

Study start
2009
Primary completion
2010
Study completion
2010
First posted
Jan 23, 2009
Registry last updated
Oct 21, 2015

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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