Clinical and Neurobiological Effects of Cannabis Dependence in Young Adults

Phase 2

Completed

Conditions: Cannabis Dependence
Cannabis Withdrawal

Interventions: Drug: placebo
Drug: rimonabant

Registration Number: NCT00656487

Lead Sponsor: The Scripps Research Institute

Brief Summary: The purpose of this study is to find out more about cognitive functioning in people who are cannabis dependent, relative to people who do not use cannabis, and how their brains process information after one month of not using cannabis. An additional goal is to characterize the severity of cannabis dependence using precipitated and naturalistic withdrawal with a double blind, placebo controlled, single administration of rimonabant. Research assessments occur bi-weekly throughout this 28 day study.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 66

Inclusion Criteria

males or females 21-30 years of age
meets Diagnostic and Statistical Manual (DSM-IV) diagnosis of Cannabis Dependence
willing to be abstinent for 28 days during study
smokes < 10 cigarettes per day
drinks < 1 (female) or < 2 (male) per day

Exclusion Criteria

active suicide ideation
meets DSM-IV diagnosis for dependence on other substances other than cannabis
significant medical disorders
pregnant women
meets DSM-IV diagnosis for a major Axis I disorder other than cannabis dependence
currently taking psychoactive medication

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Cannabis-dependent placebo	placebo	Cannabis dependent young adults administered matched placebo at Day 0 and followed for 28 days post.
Cannabis-dependent rimonabant	rimonabant	Cannabis dependent young adults administered rimonabant 90 mg at Day 0 and followed for 28 days post.

Primary Outcome Measures

Name	Time	Method
Withdrawal Symptom Severity on the Marijuana Withdrawal Checklist (MWC) at 28 Days Following Single Dose Administration of Rimonabant or Placebo, or Commencement of Monitoring, During the Double-Blind Period	Day 28	The MWC is a 28-item instrument that is used to assess the severity of frequently reported cannabis withdrawal symptoms. Each item on the measure is recorded as a severity rating between 0-3 where a zero indicates not present and a three indicates severe. The severity rating of each item was summed to obtain a single marijuana withdrawal severity score ranging between 0- 84. A lower score indicates less severe withdrawal.
Plasma Norepinephrine	Day 28	Blood samples were obtained and plasma concentrations were determined using validated enzyme-linked immunosorbent assay (ELISA) techniques at 28 days following single dose administration of rimonabant or placebo, or commencement of monitoring, during the double-blind period.
Plasma Cortisol	Day 28	Blood samples were obtained and plasma concentrations were determined using validated enzyme-linked immunosorbent assay (ELISA) techniques at 28 days following single dose administration of rimonabant or placebo, or commencement of monitoring, during the double-blind period.
Change From Day 0 in Performance on the Cambridge Neuropsychological Test Automated Batteries Spatial Working Memory (CANTAB SWM) Strategy Score at Day 28	Day 0 and Day 28	The CANTAB SWM task is a validated computer-based testing instrument assessing the memory component of executive function. Strategy Score is an estimate of use of the most efficient strategy to complete the task. Scores range from 8-56; higher scores equate to poor use of the most efficient strategy. Change = (Day 28 Score - Day 0 Score). A more negative result indicates greater improvement.
Change From Day 0 in Performance on the Cambridge Neuropsychological Test Automated Batteries Spatial Working Memory (CANTAB SWM) Total Errors at Day 28	Day 0 and Day 28	The CANTAB SWM task is a validated computer-based testing instrument assessing the memory component of executive function. Total Errors are a measure of performance and are unbounded. Change = (Day 28 Score - Day 0 Score). A more negative result indicates greater improvement.
Change From Day 0 in Performance on the Cambridge Neuropsychological Test Automated Batteries Spatial Working Memory (CANTAB SWM) Mean Time To First Response at Day 28	Day 0 and Day 28	The CANTAB SWM task is a validated computer-based testing instrument assessing the memory component of executive function. Mean Time To First Response is a measure of latency and is unbounded. Change = (Day 28 Time - Day 0 Time). A more negative result indicates greater improvement.