DrugLib.com — Drug Information Portal

Rx drug information, pharmaceutical research, clinical trials, news, and more



Clozapine for Cannabis Use in Schizophrenia

Information source: Dartmouth-Hitchcock Medical Center
ClinicalTrials.gov processed this data on August 20, 2015
Link to the current ClinicalTrials.gov record.

Condition(s) targeted: Schizophrenia; Cannabis Abuse; Cannabis Dependence; Dual Diagnosis

Intervention: Clozapine (Drug); Risperidone (Drug)

Phase: Phase 4

Status: Recruiting

Sponsored by: Dartmouth-Hitchcock Medical Center

Official(s) and/or principal investigator(s):
Alan I Green, MD, Study Chair, Affiliation: Geisel School of Medicine at Dartmouth

Overall contact:
Alan Green, MD, Phone: 603-650-7549, Email: alan.i.green@dartmuth.edu

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.

Clinical Details

Official title: Clozapine for Cannabis Use Disorder in Schizophrenia

Study design: Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Primary outcome:

Intensity of cannabis use

Frequency of cannabis use

Secondary outcome:

Symptoms of Schizophrenia

Quality of Life

Neuropsychological functioning

Reward responsiveness

Detailed description: Cannabis use disorder (CUD), which is up to ten times more common in patients with schizophrenia (SCZ) than in the general population, worsens the course of this severe psychiatric disorder. Since SCZ occurs in 1% of the population, the co-occurrence of CUD in 13% to 42% of people with this disorder presents society with an important public health problem. Unfortunately, most antipsychotics available for treatment of patients with SCZ do not appear to limit their cannabis use. Moreover, the one antipsychotic that preliminary data suggest may well limit cannabis use in these patients, clozapine (CLOZ), is not used for this purpose; it is reserved for patients whose psychosis is treatment resistant. The overarching idea behind this proposal, however, is that CLOZ's use is being unreasonably restricted and should be made more widely available for patients with SCZ who have a co-occurring CUD but whose psychosis is not necessarily treatment resistant. This notion is supported by our preliminary clinical and animal data on the effects of CLOZ, as well as our neurobiological model of the basis of cannabis use in patients with SCZ that provides a pharmacologic rationale for this effect of CLOZ. Even given all the arguments favoring the potential benefits of CLOZ in patients with SCZ and CUD, however, its side effect profile will likely limit its use until a fully powered study demonstrates its ability to decrease cannabis use in patients with SCZ. This proposal aims to launch such a study. If, as we hypothesize, this study confirms and extends our previous preliminary data of the effects of CLOZ in patients with SCZ and CUD, it will provide a strong impetus to expand the use of CLOZ in this population. In the proposed study, 132 patients who are comorbid for both SCZ and CUD will be randomized to a 12-week treatment course with either CLOZ or risperidone (RISP) to test the hypothesis that patients treated with CLOZ will have decreased cannabis use as compared to patients treated with RISP. In addition, the study will determine whether patients treated with CLOZ will have improvements in psychiatric symptoms, quality of life neuropsychological functions as compared to those taking RISP. We will also explore whether patients taking CLOZ show improved reward responsiveness as compared to those taking RISP. Finally, this study will explore whether those patients with the val/val genotype at the COMT Val158Met locus are more likely to decrease cannabis use during CLOZ treatment than are those without the val/val COMT genotype. Should this study indicate that CLOZ will lessen cannabis use in patients with SCZ more than RISP, it will provide evidence needed to begin to shift clinical practice toward its use in these patients.

Eligibility

Minimum age: 18 Years. Maximum age: 55 Years. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Clnical 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

Locations and Contacts

Alan Green, MD, Phone: 603-650-7549, Email: alan.i.green@dartmuth.edu

University of Miami, Miami, Florida 33136, United States; Recruiting
Nicole Brenson, Phone: 305-355-8186, Email: nbrenson@med.miami.edu
Philip Harvey, Ph.D., Principal Investigator

Unversity of Massachusetts Medical School, Worcester, Massachusetts 01605, United States; Recruiting
Radhika Natarajan, Phone: 508-856-8323, Email: radhika.natarajan@umassmed.edu
Xiaoduo Fan, M.D., Principal Investigator
Amy Harrington, MD, Sub-Investigator

Michigan State University / Cherry Street Health Services, Grand Rapids, Michigan 49503, United States; Recruiting
Jacob Gonzales, Phone: 616-965-8200, Ext: 7312, Email: JacobGonzales@cherryhealth.com
Eric Achtyes, MD, Principal Investigator

University of Minnesota / Ambulatory Research Center, Minneapolis, Minnesota 55454, United States; Recruiting
Victoria Patrick, Phone: 612-273-9857, Email: vpatrick@umn.edu
Charles Schulz, MD, Principal Investigator

Dartmouth Hitchcock Medical Center, Lebanon, New Hampshire 03756, United States; Recruiting
Mary Brunette, MD, Phone: 603-271-7642, Email: mary.brunette@dartmouth.edu
Christopher OKeefe, MA, Phone: 603-271-5287, Email: christopher.okeefe@dartmouth.edu
Alan I Green, MD, Principal Investigator
Mary Brunette, MD, Sub-Investigator
Douglas Noordsy, MD, Sub-Investigator

University of North Carolina/UNC Center for Excellence in Community Mental Health, Raleigh, North Carolina 27610, United States; Recruiting
Tonya Elliot, Phone: 919-966-3915, Email: tlelliot@ad.unc.edu
Fred Jarskog, MD, Principal Investigator

University of South Carolina, Columbia, South Carolina 29203, United States; Recruiting
Shalon Howard, Phone: 803-434-1642, Email: Shalon.Howard@uscmed.sc.edu
Meera Narasimhan, MD, Principal Investigator

Rutland Regional Medical Center, Rutland, Vermont 05701, United States; Recruiting
Laurie Waterman, Phone: 603-653-1802, Email: Laurie.A.Waterman@Hitchcock.org
Gordon Frankle, MD, Principal Investigator

Additional Information

Starting date: April 2013
Last updated: April 8, 2015

Page last updated: August 20, 2015

-- advertisement -- The American Red Cross
 
Home | About Us | Contact Us | Site usage policy | Privacy policy

All Rights reserved - Copyright DrugLib.com, 2006-2017