Baclofen Effects on Marijuana Dependence
Condition: Marijuana Dependence
MeSH terms: Marijuana Abuse
Intervention: Baclofen; Psychosocial; Placebo
Intervention MeSH terms: Baclofen
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 47.0
Sex: All
Minimum age: 18 Years
Maximum age: 60 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: Marijuana; Addiction; fMRI; Baclofen; Treatment

Summary:

      Studies show that certain reminders of drug use such as the sight of someone using marijuana,
      pictures of blunts, particular moments throughout the day, prompt marijuana users to smoke
      marijuana. We are measuring the brain and behavioral responses of marijuana dependent
      individuals to these reminders (cues) We will examine brain responses during cue exposure and
      determine whether these responses are associated with treatment outcome.

      We are testing the hypothesis that the medication baclofen reduces brain responses during
      marijuana cue exposure and/or craving in marijuana dependent individuals. Baclofen is
      FDA-approved for other uses, but not for the treatment of marijuana dependence. Functional
      magnetic resonance imaging (fMRI) will be used to measure the brain's response to marijuana
      cues. fMRI is a painless technique that takes special pictures of the brain (or other parts
      of your body). It does not involve radiation or injections.

      Eligible participants will have a 50% chance of receiving placebo (sugar pill) and a 50%
      chance of receiving baclofen. Neither the participant nor study personnel will know whether
      participants are receiving baclofen or placebo. Participants will also receive twice weekly
      psychosocial treatment with a certified clinician. Twelve weeks of treatment will be followed
      by a 12 week follow up.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Physically healthy, as determined by a comprehensive physical examination and approval
             of the study physician, and mentally stable, as determined by a psychological
             evaluation by a licensed clinician, males or females who meet Diagnostic and
             Statistical Manual of Mental Disorders-IV (DSM-IV) criteria for marijuana dependence,
             ages 18-60.

          -  Must be able to read. [Subjects are required to be able to read because there are
             several self-administered measures that they must read, understand and provide written
             answers.]

          -  Females must be non-pregnant, non-lactating and either be of non-childbearing
             potential (i.e. sterilized via hysterectomy or bilateral tubal ligation or at least 1
             year post-menopausal) or of child bearing potential but practicing a medically
             acceptable method of birth control. Examples of medically acceptable methods for this
             protocol include barrier (diaphragm or condom) with spermicide, an intrauterine device
             (IUD), the Nuvaring, oral contraceptives, levonorgestrel implant, hormonal injection
             or complete abstinence.

          -  Intelligence quotient of ≥ 80.

          -  Provide voluntary informed consent.

        Exclusion Criteria:

          -  Participation in a clinical trial and receipt of investigational drug(s) during the
             previous 60 days.

          -  Presence of magnetically active irremovable prosthetics, plates, pins, permanent
             retainer, bullets, etc. (unless a radiologist confirms that it's presence is
             unproblematic). An x-ray may be obtained to determine eligibility given the
             possibility of a foreign body.

          -  Current use of non-removable medicated or nicotine skin patches.

          -  Current or prior gambling problems (assessed by subject's self-report).

          -  Current treatment for marijuana dependence.

          -  Any other current drug dependence diagnoses (except nicotine dependence).

          -  Any other psychiatric diagnoses. Current diagnosis/recent history (within past 6
             months) of Major Depressive Disorder (MDD).

          -  History of head trauma or injury causing loss of consciousness, lasting more than
             three (3) minutes or associated with skull fracture or inter-cranial bleeding or
             abnormal Magnetic Resonance Imaging (MRI).

          -  Claustrophobia or other medical condition preventing subject from lying in the MRI for
             approximately one (1) hour.

          -  Clinically significant cardiovascular, hematologic, hepatic (liver), renal (kidney),
             neurological, or endocrinological abnormalities, bloodwork, and/or electrocardiogram
             (EKG).

          -  Uncontrolled diabetes or uncontrolled hypertension.

          -  History of psychosis, seizures, or organic brain syndrome.

          -  Vision problems that cannot be corrected with glasses.

          -  Weight exceeding 300 pounds [Imaging data acquisition is impaired with high weight
             individuals].

          -  History of stroke.

        Case-by-Case:

          -  Human immunodeficiency virus (HIV) positive on medication for symptoms. This will be
             determined on an individual basis by results from the physical examination and final
             approval by our study physician; all results from the physical within normal range for
             study inclusion.

          -  Use of medications or natural herbs that cause sedation or affect the brain systems
             that are being studied. Medication use will be evaluated by our study physician on a
             case-by-case basis. For example, if the subject takes Benadryl but can safely refrain
             from use 24 hours prior to scanning sessions, they will not be excluded.

          -  Significant history of past alcohol or substance abuse.