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NCT01639872 · ClinicalTrials.gov registry record · Phase 4
Clozapine for Cannabis Use in Schizophrenia
A Phase 4 study, sponsored by Dartmouth-Hitchcock Medical Center.
- Completed
- Registry status
- Phase 4
- Development phase
- 49
- Enrollment target
NCT01639872: Completed Phase 4 study, sponsored by Dartmouth-Hitchcock Medical Center.
NCT01639872 is a Phase 4 study that has completed, run by Dartmouth-Hitchcock Medical Center. The registered enrollment target is 49 participants, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (91% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT01639872, a Phase 4 study, has completed, sponsored by Dartmouth-Hitchcock Medical Center.
- COMPLETED
- Registry status
- Phase 4
- Development phase
- 49 participants
- Enrollment target
Study 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.
Primary Outcome
Intensity of cannabis use is obtained each week retrospectively as the number of joints smoked during the prior week (assessed using the Timeline Followback). Mixed models are used to obtain estimates of efficacy from the partial data provided by each subject while adherent to assigned treatment (under the 'missing at random' assumption). The 'explanatory' estimands (target of the mixed model estimation) are defined in terms of population quantities that would have occurred had all subjects rema
Interventions
- DRUG Risperidone
- DRUG Clozapine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 49 participants |
| Start Date | 2013-05-01 |
| Est. Completion | 2017-03-29 |
| Phase | Phase 4 |
What the finished NCT01639872 record still lists
NCT01639872 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 49 participants, a relatively small participant target, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (91% lower).
The record links to 0 conditions, and to 2 interventions - of which Risperidone is the first listed.
NCT01639872 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT01639872 about?
NCT01639872 is a clinical study titled "Clozapine for Cannabis Use in Schizophrenia". 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...
What is the current status of trial NCT01639872?
This trial is currently completed. It is a Phase 4 study. The enrollment target is 49 participants. The study started on 2013-05-01. Estimated completion is 2017-03-29.
What interventions are being tested in trial NCT01639872?
The interventions under investigation include: Risperidone (DRUG), Clozapine (DRUG).
Who is sponsoring clinical trial NCT01639872?
This trial is sponsored by Dartmouth-Hitchcock Medical Center, which has 427 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT01639872's enrollment target sits among peer trials
49 1323rd of 2000 higher than 670 of 2,000 other Phase 4 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 4 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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