Buspirone Treatment for Marijuana Dependence

Marijuana is the most commonly used illicit drug, yet few clinical trials have evaluated pharmacotherapy treatments for marijuana dependence. This study will evaluate the efficacy of buspirone for reducing marijuana use in marijuana-dependent adults. A contingency management (CM) intervention and motivational enhancement therapy (MET) will be incorporated to encourage study engagement and retention. It is hypothesized that buspirone combined with MET and CM will reduce the percent of marijuana-positive urine drug screen results in marijuana-dependent individuals as compared to a placebo treatment combined with MET and CM.

Study Overview

• Status: Completed
• Conditions: Marijuana Dependence
• Intervention / Treatment: Drug: Buspirone; Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 175
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • South Carolina
    • Charleston, South Carolina, United States, 29425
      • Medical University of South Carolina

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Must meet DSM-IV criteria for marijuana dependence.
• Must be between the ages of 18 and 65 years.
• If female and of childbearing potential, must agree to use acceptable methods of birth control for the duration of the trial.
• Must consent to random assignment, and be willing to commit to psychosocial behavioral and medication treatment.
• Must be able to read and provide informed consent.

Exclusion Criteria:

• Women who are pregnant, nursing, or plan to become pregnant during the course of the study.
• Must not have a history of or current psychotic disorder, bipolar disorder, or eating disorder.
• Must not pose a current suicidal or homicidal risk.
• Must not meet current criteria for major depression.
• Must not have evidence or history of serious hematologic, endocrine, cardiovascular, pulmonary, renal, gastrointestinal or neurologic disease.
• Must not require concomitant therapy with psychotropic medication.
• Must not be currently dependent on other substances, with the exception of nicotine or caffeine.
• Hypersensitivity to buspirone or any other product component.
• Patients who, in the investigator's opinion, would be unable to comply with study procedures or assessments, or would be unacceptable study candidates (e.g., poses threat to staff).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo	Drug: Placebo; Flexible dose, up to 60 mg daily
Experimental: Buspirone	Drug: Buspirone; Flexible dose, up to 60 mg daily; Other Names: Buspar

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Marijuana-negative Urine Drug Screens (UDS)	Participants submitted a urine sample weekly. Percentage of marijuana negative urine samples were calculated per group.	Participants provided a once-weekly urine sample for twelve weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Retention in the Study	Number of days subjects remained active in the study	participants were followed for twelve weeks
Marijuana Craving	The Marijuana Craving Questionnaire (MCQ) is intended to measure marijuana craving in adults. It measures symptoms on four subscales: expectancy, purposefulness, emotionality, and compulsivity. The scale rates individual items from 1 (least craving) - 7 (most craving) with a composite scoring range of 12-84 and possible subscale scoring range of 3-21. It was administered weekly- reported here is the mean composite score across the 8 week treatment course.	8 Weeks

Collaborators and Investigators

• Sponsor: Medical University of South Carolina
• Collaborators: National Institute on Drug Abuse (NIDA)

Study record dates

Study Major Dates

• Study Start: September 1, 2009
• Primary Completion (Actual): June 1, 2014
• Study Completion (Actual): March 1, 2016

Study Registration Dates

• First Submitted: April 2, 2009
• First Submitted That Met QC Criteria: April 2, 2009
• First Posted (Estimate): April 3, 2009

Study Record Updates

• Last Update Posted (Estimate): August 10, 2016
• Last Update Submitted That Met QC Criteria: July 8, 2016
• Last Verified: July 1, 2016

More Information

Terms related to this study

• Keywords: Marijuana; Contingency management; Buspirone; Motivational enhancement therapy
• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders; Marijuana Abuse; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Tranquilizing Agents; Psychotropic Drugs; Serotonin Agents; Serotonin Receptor Agonists; Anti-Anxiety Agents; Buspirone
• Other Study ID Numbers: R01DA026782 (U.S. NIH Grant/Contract); DPMCDA (Other Identifier: NIDA)