Treatment for Cannabis Withdrawal and Dependence
Condition: Cannabis Dependence
MeSH terms: Marijuana Abuse
Study type: Interventional
Phase: Phase 2

Summary: 
      Cannabis is the most widely used illicit drug in the United States, and worldwide, with 1 in
      10 users estimated to meet diagnostic criteria for cannabis dependence. Avoidance of
      withdrawal symptoms (e.g., disturbances in mood, sleep, and craving) is a common relapse
      precipitant. Cannabis use also impairs executive cognitive functions thereby increasing
      vulnerability to relapse and reducing the ability to benefit from behavioral therapy. There
      are no pharmacological treatments for cannabis dependence, despite the large number of
      afflicted individuals and the limitations of behavioral therapies which do not remediate
      withdrawal and are associated with high rates of treatment failure. The primary aim of this
      clinical trial is to evaluate the efficacy and safety of a novel neurokinin1 (NK1) receptor
      antagonist, aprepitant (Emend), (125mg/day), in outpatients with current cannabis dependence.
      The main hypothesis to be tested is to evaluate the relative efficacy of aprepitant 125 mg/d
      vs. placebo for reducing cannabis withdrawal symptoms in cannabis dependent outpatients,
      specifically anxiety, mood, craving and sleep.
    

Detailed description: 
      This study will be a Phase II, single-site, 8-week, randomized, double-blind,
      placebo-controlled, parallel group comparison of aprepitant (125 mg/d) or placebo. Subjects
      will be 100 outpatients seeking treatment for current cannabis dependence with no clinically
      significant medical or psychiatric disorders (including substance use disorders or a positive
      drug screen for substances other than cannabis or nicotine). All subjects will receive weekly
      manual-guided abstinence-oriented counseling to facilitate showing a drug effect above and
      beyond available therapies (Weeks 0-8). Research assessments of marijuana use and withdrawal
      and drug safety and tolerability will occur weekly through the treatment phase of the 8-week
      study. Post treatment follow-up assessments will occur at Weeks 9 and 12. Neuropsychological
      testing will occur at Weeks 0 and 4 and 8.

      Specific Aim 1: To evaluate the relative efficacy of aprepitant 125 mg/d vs. placebo for
      reducing cannabis withdrawal symptoms in cannabis dependent outpatients, including anxiety,
      mood, craving and sleep symptoms.

      Specific Aim 2: To evaluate the relative efficacy of aprepitant 125 mg/d vs. placebo for
      reducing marijuana use in cannabis dependent outpatients.

      Specific Aim 3: To evaluate the relative efficacy of aprepitant 125 mg/d vs. placebo for
      reducing cannabis related impairments in executive functioning in cannabis dependent
      outpatients.
    

Intervention name(s): Aprepitant; Placebo; Manual-guided behavioral counseling
Intervention type(s): Drug; Drug; Behavioral
Intervention description(s): 125mg/day for 8 weeks; 125mg/d placebo pill for 8 weeks; Standardized manual-guided behavioral counseling performed 1 time per week for 8 weeks in conjunction with study drug or placebo.
Other intervention name(s): Emend; Manual-guided therapy
Intervention MeSH terms: Aprepitant
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment