Gabapentin Treatment of Cannabis Dependence

Phase 2

Completed

• Conditions: Cannabis Dependence
• Interventions: Drug: Placebo; Drug: Gabapentin

• Registration Number: NCT00395044
• Lead Sponsor: The Scripps Research Institute

Brief Summary

This is a study to evaluate the efficacy of the medication gabapentin in treating persons with cannabis dependence.

Detailed Description

This is a 12-week, double blind, placebo controlled, dose ranging study to evaluate the efficacy of gabapentin in treating outpatients with cannabis dependence. Counseling and research assessments occur weekly throughout the 12-week treatment phase.

Study Timeline

• Study Start: 2006-08
• Study First Submitted: 2006-11-01
• Study First Submitted QC: 2006-11-01
• Study First Posted: 2006-11-02
• Primary Completion: 2008-07
• Study Completion: 2008-07
• Results First Submitted: 2013-03-15
• Status Verified: 2016-12
• Results First Submitted QC: 2016-12-19
• Last Update Submitted: 2016-12-19
• Results First Posted: 2017-02-10
• Last Update Posted: 2017-02-10

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

• Males or females age 18-65 with cannabis dependence
• Meets DSM-IV-TR criteria for Cannabis Dependence
• Smoked marijuana at least once a week in the 90 days prior to study participation
• Willing to attend 12 weekly study visits and 1 follow-up visit

Exclusion Criteria

• Currently meets DSM-IV-TR criteria for dependence on illicit substances other than cannabis
• Significant medical disorders that will increase potential risk or interfere with study participation
• Women with childbearing potential who are pregnant, nursing, or refuse to use a reliable method of birth control
• Treatment with an investigational drug in the last month

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	1200mg/d of Placebo
Gabapentin	Gabapentin	1200 mg/daily of Gabapentin

Primary Outcome Measures

Name	Time	Method
Change From Week 0 in Cannabis Use Using Urinary CN-THCCOOH Levels at Week 12	Week 0 and Week 12	Urinary THC/Cr ratio, also known as CN-THCCOOH (creatinine normalized tetrahydrocannabinol carboxylic acid), is a highly sensitive and specific quantitative analytic procedure to determine current marijuana metabolite levels in the urine as well as new marijuana use or abstinence. Gas chromatography-mass spectrometric levels of 11-nor-9-carboxy-9-THC (THC-COOH), the primary marijuana metabolite, are normalized to the urine creatinine (CN) concentration to reduce the variability of drug measurement attributable to urine dilution. Negative values indicate decreased use.

Secondary Outcome Measures

Name	Time	Method
Change From Week 0 in Withdrawal Symptom Severity on the Marijuana Withdrawal Checklist (MWC) at Week 12	Week 0 and Week 12	The MWC is an instrument to assess the severity of frequently reported cannabis withdrawal symptoms. Each question on the measure is recorded as a severity rating between 0-3: 0=best outcome; 3=worst outcome. The severity rating of each question was averaged to obtain a single marijuana withdrawal severity score. Change = (Week 12 score - Week 0 score).
Change in Sleep Quality on the Pittsburgh Sleep Quality Index (PSQI) at Week 12	Week 0 and Week 12	The PSQI is an instrument to assess subjective sleep quality and disturbance. The range on the measure is from 0-21: 0=best outcome; 21=worst outcome. Change = (Week 12 score - Week 0 score).
Change From Week 0 in Mood on the Beck Depression Inventory (BDI-II) at Week 12	Week 0 and Week 12	The BDI-II is a self-rating of severity of depressive symptoms. The Total score range on the BDI-II is from 0-63; 0=best outcome; 63=worst outcome. Change = (Week 12 score - Week 0 score).
Change From Week 0 in Craving on the Marijuana Withdrawal Checklist Marijuana Craving Question at Week 12	Week 0 and Week 12	The Marijuana Craving question of the Marijuana Withdrawal Checklist assesses severity of craving to smoke marijuana. The craving question is rated on a scale of 0-3 where 0=best outcome (no symptoms) and 3=worst outcome (severe symptoms). Change = (Week 12 score - Week 0 score).
Change From Baseline in Cognitive Functioning Using the Delis-Kaplan Executive Function System (D-KEFS) at Week 4	Week 0 and Week 4	The D-KEFS is a testing battery designed to measure executive functioning, a critical component of participating in cognitive behavioral therapy used to treat marijuana dependence. Data were obtained from the D-KEFS test instruments completed at baseline and week 4, which included the Trail Making Test, Verbal Fluency Test, and Color-Word Interference Test. Scaled scores range from 1 (worst) to 19 (best). Change = (Week 4 score - Week 0 score). Positive values indicate increased executive functioning.
Change From Week 0 in Cannabis-related Problems on the Marijuana Problem Scale (MPS) at Week 12	Week 0 and Week 12	The MPS is an instrument to assess the incidence of physical, psychological, social, and functioning problems that can result from cannabis dependence. The Total score ranges from 0-38 where 0=best outcome and 38=worst outcome. Change = (Week 12 score - Week 0 score).

Trial Locations

Locations (1)

The Scripps Research Institute; 🇺🇸 La Jolla, California, United States