Using clozapine to reduce violence in people with schizophrenia

Clozapine for the Prevention of Violence in Schizophrenia: a Randomized Clinical Trial

Phase 4 Interventional New York State Psychiatric Institute · NCT05208190

This study is testing if the medication clozapine can help reduce violent behavior in adults with schizophrenia or schizoaffective disorder.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment280 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorNew York State Psychiatric Institute Academic / other
Locations7 sites (Los Angeles, California and 6 other locations)
Trial IDNCT05208190 on ClinicalTrials.gov

What this trial studies

This clinical trial involves 280 adults aged 18-65 with schizophrenia or schizoaffective disorder who have a recent history of violent behavior. Participants will be randomly assigned to receive either clozapine or standard antipsychotic treatment for 24 weeks. The study aims to evaluate the effectiveness of clozapine in reducing the risk of future violent acts, using assessments such as the MacArthur Community Violence Interview. Participants will undergo medical monitoring, including blood tests and physical exams, throughout the trial.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18-65 with a diagnosis of schizophrenia or schizoaffective disorder who have committed a violent act within the last six months.

Not a fit: Patients with unstable medical conditions or a history of severe adverse reactions to clozapine may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could significantly reduce the risk of violent behavior in individuals with schizophrenia, improving safety for both patients and the community.

How similar studies have performed: While there have been studies on clozapine's effectiveness in treating schizophrenia, this specific approach to reducing violence is novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Diagnostic and Statistical Manual-5 (DSM-5) diagnosis of schizophrenia or schizoaffective disorder by the Structured Clinical Interview for DSM-5 (SCID-5)
* commission of a minor or serious act of violence as measured by the MCVI in the last six months
* willing and able to provide informed consent
* medically stable in judgment of physician providing study treatment
* appropriate for treatment with either clozapine or TAU, i.e., that there is clinical equipoise between the two treatment options. Individuals who are currently medication free or on any antipsychotic, with the exception of clozapine or long-acting injectable medication with a dosing interval of more than 30 days will be eligible

Exclusion Criteria:

* An unstable of serious medical or neurological condition including a myeloproliferative disorder or condition that surprises the bone marrow
* A history of intolerance/allergy to clozapine (e.g., agranulocytosis, small bowel obstruction, or myocarditis)
* A history of intellectual impairment
* pregnant or lactating women; women who are able to become pregnant but who are not willing to sue effective methods of birth control
* Individuals who score a 3, 4, or 5 within the previous month on the suicidal ideation section of the Columbia Suicide Severity Rating Scale (CSSRS), have any suicidal behavior (not including Not Suicidal Self Injury) within the previous 3 months, or are, in the opinion of the investigator, at too high of a risk for suicide to be safety treated in a randomized trial in which they may not be treated with clozapine
* Documented intolerance to or lack of any therapeutic benefit with clozapine after a full trial

Where this trial is running

Los Angeles, California and 6 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions SchizophreniaSchizoaffective Disorder
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.