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Clozapine and Olanzapine Treatment of Aggression

This study has been completed.
Information provided by:
Nathan Kline Institute for Psychiatric Research Identifier:
First received: May 12, 2010
Last updated: May 13, 2010
Last verified: May 2010
This was a double-blind randomized study with three treatment arms: clozapine, olanzapine and haloperidol. We compared these three medications in the treatment of aggressive behavior over a 12 week period.

Condition Intervention
Schizophrenia Drug: Clozapine Drug: Olanzapine Drug: Haloperidol

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Clozapine and Olanzapine in the Treatment of Violence in Schizophrenic Patients

Resource links provided by NLM:

Further study details as provided by Nathan Kline Institute for Psychiatric Research:

Primary Outcome Measures:
  • Number of aggressive incidents [ Time Frame: 12 weeks ]
    The Modified Overt Aggression scale (MOAS) was used to record all aggressive incidents. The primary measure was the total score on the MOAS as well as the score on the MOAS physical aggression subscale

Secondary Outcome Measures:
  • Psychiatric Symptoms [ Time Frame: 12 weeks ]
    Psychiatric symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS) weekly for the first 4 weeks and then bi-weekly for the remainder of the study

  • Side effects of medications [ Time Frame: 12 weeks ]
    The side effects of the medications were measured with the ESRS on a weekly basis for the duration of the study

Enrollment: 110
Study Start Date: June 1999
Study Completion Date: July 2004
Primary Completion Date: July 2004 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: clozapine
During the first 6 weeks clozapine was gradually increased to 500 mg/day and then continued. For the next period, it could vary from 200-800 mg/day;
Drug: Clozapine
500 mg/day
Other Name: clozaryl
Experimental: Olanzapine
During the first 6 weeks olanzapine was increased to 20 mg and remained fixed for until the end of six week. During the last 6 weeks olanzapine could vary from 10 to 30 mg/day
Drug: Olanzapine
20 mg/day
Other Name: zyprexa
Active Comparator: Haloperidol
During the first 6 weeks haloperidol was increased to 20 mg and remained fixed for until the end of six week. During the last 6 weeks the dose could vary from 10 to 30 mg/day
Drug: Haloperidol
20 mg/day
Other Name: Haldol

Detailed Description:

Objective: The purpose of our study was the investigation of the effect of atypical antipsychotic agents on interpersonal violence and aggression.

We compared the efficacy of two atypical antipsychotic agents, clozapine and olanzapine with one another and with haloperidol in the treatment of physical assaults and other assaultive behaviors in physically assaultive patients with schizophrenia and schizoaffective disorder.

Method: The subjects were 110 physically assaultive inpatients diagnosed with schizophrenia or schizoaffective disorder.

They were randomly assigned to treatment with clozapine (N=37), olanzapine (N=37) or haloperidol (N=36) in a 12-week, double-blind trial. Incidents of overt aggression were recorded and their severity was scored with the Modified Overt Aggression Scale (MOAS). Psychiatric symptoms were assessed through the Positive and Negative Syndrome Scale (PANSS). We also assessed various side effects and monitored vital signs and drew bloods.


Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age: 18 to 60 years.
  • Diagnosis of schizophrenia or schizoaffective disorder.
  • Aggression: One episode of physical assault directed at another person in the hospital and persistence of violence/hostility for two weeks, as evidenced by the presence of some other physical, verbal or property assault or hostility, which would result in a score of 4 or more on the Positive and Negative Syndrome Scale (PANSS) Hostility Item.

Exclusion Criteria:

  • Patients who were hospitalized for more than a year
  • Patients who had a history of nonresponse to clozapine, olanzapine or haloperidol (defined as a lack of improvement despite a contiguous adequate trial of medication)
  • Patients who had a history of clozapine, olanzapine, or haloperidol intolerance
  • Patients who had medical conditions that would be adversely affected by any of these three medications.
  • Patients who received a depot antipsychotic within 30 days before randomization.
  Contacts and Locations
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Please refer to this study by its identifier: NCT01123408

United States, New York
Nathan Kline Institute
Orangeburg, New York, United States, 10962
Sponsors and Collaborators
Nathan Kline Institute for Psychiatric Research
Study Director: Bennett L Leventhal, MD Nathan Kline Institute
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Krakowski, Menahem, Nathan Kline Institute Identifier: NCT01123408     History of Changes
Other Study ID Numbers: 2244
Study First Received: May 12, 2010
Last Updated: May 13, 2010

Keywords provided by Nathan Kline Institute for Psychiatric Research:

Additional relevant MeSH terms:
Schizophrenia Spectrum and Other Psychotic Disorders
Mental Disorders
Behavioral Symptoms
Haloperidol decanoate
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Gastrointestinal Agents
Antipsychotic Agents
Tranquilizing Agents
Central Nervous System Depressants
Psychotropic Drugs
Serotonin Uptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Serotonin Agents
Dopamine Antagonists
Dopamine Agents
Anti-Dyskinesia Agents
Serotonin Antagonists
GABA Antagonists
GABA Agents processed this record on July 21, 2017