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Atypical Antipsychotic

Clozapine vs Risperidone for Psychosis

Phase 4
Recruiting
Research Sponsored by University of Texas Southwestern Medical Center
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
18-60y/o; males and females; all races and ethnicities
Medically stable
Timeline
Screening 3 weeks
Treatment Varies
Follow Up week 4, week 10 and week 18
Awards & highlights

Study Summary

This trial is designed to study the effects of the medication clozapine on people with psychosis, including schizophrenia, schizoaffective disorder, and psychotic bipolar I disorder. The trial will compare the effects of clozapine to a control group taking risperidone. The study sample will be comprised of n=524 individuals with psychosis, who will be randomly assigned to either the clozapine group or the control group. The investigators plan to follow the participants for a biomedical outcome.

Who is the study for?
This trial is for adults aged 18-60 with schizophrenia, schizoaffective disorder, or bipolar I with psychotic features. Participants must be medically stable, have a certain level of symptom severity, and not belong to vulnerable groups like pregnant women. They shouldn't have used clozapine before or certain long-acting antipsychotics recently.Check my eligibility
What is being tested?
The study compares the effects of clozapine versus risperidone on individuals with specific types of psychosis. It's a rigorous test where participants are randomly assigned to one of the drugs in a controlled environment across multiple sites to see which drug works better for their condition.See study design
What are the potential side effects?
Clozapine can cause side effects such as drowsiness, increased saliva production, constipation, and potentially serious blood disorders. Risperidone may lead to movement disorders, weight gain, fatigue and an increased risk for diabetes.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
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I am between 18 and 60 years old.
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My health condition is currently stable.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~week 4, week 10 and week 18
This trial's timeline: 3 weeks for screening, Varies for treatment, and week 4, week 10 and week 18 for reporting.

Treatment Details

Study Objectives

Outcome measures can provide a clearer picture of what you can expect from a treatment.
Primary outcome measures
Change in the PANSS total score

Trial Design

4Treatment groups
Experimental Treatment
Active Control
Placebo Group
Group I: Biotype 1 - Clozapine (B1C)Experimental Treatment1 Intervention
Target doses will be up to clozapine 500mg po qd. In addition, several concomitant (open label) medications for symptomatic management will be available via the study protocol [non-benzodiazepine sleep aid (melatonin, hydroxyzine); motor side effect treatments (benztropine, propranolol)]. The doses for these medications will be consistent with those routinely used in a clinical practice: melatonin [up to 10mg at bedtime], hydroxyzine [up to 100mg at bedtime]; benztropine [up to 4mg/day (2mg twice/day)], propranolol [up to 40mg/day (20mg twice/day)].
Group II: Biotype 2 - Clozapine (B2C)Active Control1 Intervention
Target doses will be up to clozapine 500mg po qd. In addition, several concomitant (open label) medications for symptomatic management will be available via the study protocol [non-benzodiazepine sleep aid (melatonin, hydroxyzine); motor side effect treatments (benztropine, propranolol)]. The doses for these medications will be consistent with those routinely used in a clinical practice: melatonin [up to 10mg at bedtime], hydroxyzine [up to 100mg at bedtime]; benztropine [up to 4mg/day (2mg twice/day)], propranolol [up to 40mg/day (20mg twice/day)].
Group III: Biotype 2 - Risperidone (B2R)Placebo Group1 Intervention
Target doses will be up to risperidone 6mg po qd. In addition, several concomitant (open label) medications for symptomatic management will be available via the study protocol [non-benzodiazepine sleep aid (melatonin, hydroxyzine); motor side effect treatments (benztropine, propranolol)]. The doses for these medications will be consistent with those routinely used in a clinical practice: melatonin [up to 10mg at bedtime], hydroxyzine [up to 100mg at bedtime]; benztropine [up to 4mg/day (2mg twice/day)], propranolol [up to 40mg/day (20mg twice/day
Group IV: Biotype 1 - Risperidone (B1R)Placebo Group1 Intervention
Target doses will be up to risperidone 6mg po qd. In addition, several concomitant (open label) medications for symptomatic management will be available via the study protocol [non-benzodiazepine sleep aid (melatonin, hydroxyzine); motor side effect treatments (benztropine, propranolol)]. The doses for these medications will be consistent with those routinely used in a clinical practice: melatonin [up to 10mg at bedtime], hydroxyzine [up to 100mg at bedtime]; benztropine [up to 4mg/day (2mg twice/day)], propranolol [up to 40mg/day (20mg twice/day)].
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
clozapine
2006
N/A
~20

Find a Location

Who is running the clinical trial?

University of GeorgiaOTHER
100 Previous Clinical Trials
34,134 Total Patients Enrolled
1 Trials studying Schizophrenia
70 Patients Enrolled for Schizophrenia
Beth Israel Deaconess Medical CenterOTHER
835 Previous Clinical Trials
13,006,121 Total Patients Enrolled
21 Trials studying Schizophrenia
1,478 Patients Enrolled for Schizophrenia
Hartford HospitalOTHER
133 Previous Clinical Trials
18,406 Total Patients Enrolled
3 Trials studying Schizophrenia
262 Patients Enrolled for Schizophrenia

Media Library

Clozapine (Atypical Antipsychotic) Clinical Trial Eligibility Overview. Trial Name: NCT04580134 — Phase 4
Schizophrenia Research Study Groups: Biotype 2 - Risperidone (B2R), Biotype 2 - Clozapine (B2C), Biotype 1 - Clozapine (B1C), Biotype 1 - Risperidone (B1R)
Schizophrenia Clinical Trial 2023: Clozapine Highlights & Side Effects. Trial Name: NCT04580134 — Phase 4
Clozapine (Atypical Antipsychotic) 2023 Treatment Timeline for Medical Study. Trial Name: NCT04580134 — Phase 4
Schizophrenia Patient Testimony for trial: Trial Name: NCT04580134 — Phase 4

Frequently Asked Questions

These questions and answers are submitted by anonymous patients, and have not been verified by our internal team.

Does the Food and Drug Administration recognize clozapine as an accepted treatment?

"The safety of clozapine is confidently rated at 3 on our 1-3 scale, as this treatment has been approved by the FDA and is currently in Phase 4 trials."

Answered by AI

What are the qualifications for participating in this experiment?

"To qualify for this trial, applicants must have schizophrenia and an age between 18-55 years. The research team is recruiting approximately 524 people to participate in the study."

Answered by AI

Are there any available openings in this clinical research study?

"Affirmative. Per the information on clinicaltrials.gov, recruitment for this trial is ongoing. It was posted to the database on January 24th 2022 and updated most recently February 22nd 2022; 524 individuals are needed at a single location."

Answered by AI

What is the current capacity of participants for this investigation?

"Affirmative. According to clinicaltrials.gov, this medical trial has begun recruitment and requires 524 participants at a single site. The information was initially posted on January 24th 2022 before being updated on February 22nd of the same year."

Answered by AI

What is the primary purpose of clozapine treatment?

"Clozapine has proven to be a successful intervention for acute coryza, treatment-resistant schizophrenia, and situations where other therapies have failed."

Answered by AI

Does this clinical trial invite participants aged 80 or older?

"This experiment is open to participants aged 18-55 years old."

Answered by AI

Has clozapine been the subject of any prior investigations?

"Presently, 17 trials centred around clozapine are underway with 1 of them in its third phase. Toronto is the primary site for these studies; however, there are 139 locations across North America that have registered clinical trials involving this medication."

Answered by AI

Who else is applying?

What state do they live in?
Texas
What site did they apply to?
UT Southwestern Medical Center
What portion of applicants met pre-screening criteria?
Met criteria
How many prior treatments have patients received?
1

Why did patients apply to this trial?

I have tried other medications and I am still having symptoms.
PatientReceived no prior treatments
~245 spots leftby Dec 2025