Phase 4
Completed N=49
Clozapine for Cannabis Use in Schizophrenia
Schizophrenia · Cannabis Abuse · Cannabis Dependence · Dual Diagnosis
Source: ClinicalTrials.gov NCT01639872 ↗
Enrolled (actual)
49
Serious AEs
12.8%
Results posted
Dec 2019
Primary outcomePrimary: Average Over Time of Intensity of Cannabis Use (Used to Evaluate Treatment Efficacy) — 10.21; 10.2 joints smoked during the prior week — p=.99
◆ Published Evidence
No publication linked
No peer-reviewed publication reporting this trial's results has been linked yet. This can indicate results are unpublished — a known publication-bias signal. We re-check periodically.
Summary
Many individuals with schizophrenia also suffer from marijuana addiction that worsens their problems related to schizophrenia. Most of the medications prescribed for schizophrenia have no effect on reducing marijuana use. Preliminary data suggests that clozapine, an atypical antipsychotic, may limit marijuana use in people diagnosed with schizophrenia, but it is not commonly used due to its side effects and is reserved for people who do not respond to other antipsychotic medications.
In the proposed study, 132 individuals who are diagnosed with both schizophrenia and a cannabis use disorder will be randomized to a 12-week treatment course with either clozapine or risperidone (another commonly prescribed antipsychotic medication) to test the hypothesis that patient treated with clozapine will have decreased cannabis use as compared to patients treated with risperidone.
Should this study indicate that clozapine will lessen marijuana use in persons diagnosed with schizophrenia more than risperidone, it will provide evidence needed to begin to shift clinical practice toward its use in this population.
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Average Over Time of Intensity of Cannabis Use (Used to Evaluate Treatment Efficacy) |
10.21; 10.2 | .99 |
| PRIMARY Average Over Time of Frequency of Cannabis Use |
4.26; 4.58 | .25 |
Eligibility Criteria
Inclusion Criteria
- Clinical diagnosis of schizophrenia
- Clinical diagnosis of a cannabis use disorder (abuse or dependence)
Exclusion Criteria
- Pregnant,trying to become pregnant or nursing
- History of a seizure disorder
- Current treatment with clozapine or risperidone
- Contraindication to treatment with clozapine or risperidone
Data sourced from ClinicalTrials.gov (NCT01639872). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication. Informational only — not medical advice.