Marijuana Dependence
Conditions
Keywords
Marijuana, Buspirone, Contingency management, Motivational enhancement therapy
Brief summary
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.
Interventions
DRUGBuspirone
Flexible dose, up to 60 mg daily
DRUGPlacebo
Flexible dose, up to 60 mg daily
Sponsors
National Institute on Drug Abuse (NIDA)
Medical University of South Carolina
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
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).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent Marijuana-negative Urine Drug Screens (UDS) | Participants provided a once-weekly urine sample for twelve weeks | Participants submitted a urine sample weekly. Percentage of marijuana negative urine samples were calculated per group. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Retention in the Study | participants were followed for twelve weeks | Number of days subjects remained active in the study |
| Marijuana Craving | 8 Weeks | 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. |
Countries
United States
Participant flow
Recruitment details
Participants recruited between November 2009 and March 2014 primarily through media and internet advertisements.
Participants by arm
| Arm | Count |
|---|---|
| Buspirone Buspirone: 30 mg capsules twice daily | 88 |
| Placebo Placebo: 30 mg capsules twice daily | 87 |
| Total | 175 |
Baseline characteristics
| Characteristic | Buspirone | Placebo | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 88 Participants | 87 Participants | 175 Participants |
| Region of Enrollment United States | 88 participants | 87 participants | 175 participants |
| Sex: Female, Male Female | 21 Participants | 20 Participants | 41 Participants |
| Sex: Female, Male Male | 67 Participants | 67 Participants | 134 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 73 / 88 | 66 / 87 |
| serious Total, serious adverse events | 0 / 88 | 0 / 87 |
Outcome results
Primary
Percent Marijuana-negative Urine Drug Screens (UDS)
Participants submitted a urine sample weekly. Percentage of marijuana negative urine samples were calculated per group.
Time frame: Participants provided a once-weekly urine sample for twelve weeks
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Buspirone | Percent Marijuana-negative Urine Drug Screens (UDS) | 7.2 percentage of UDS |
| Placebo | Percent Marijuana-negative Urine Drug Screens (UDS) | 6.4 percentage of UDS |
Secondary
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.
Time frame: 8 Weeks
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Buspirone | Marijuana Craving | 29.6 units on a scale |
| Placebo | Marijuana Craving | 28.4 units on a scale |
Secondary
Retention in the Study
Number of days subjects remained active in the study
Time frame: participants were followed for twelve weeks
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Buspirone | Retention in the Study | 79 Day |
| Placebo | Retention in the Study | 84 Day |