Clinical trial NCT00149630
Conditions: Cocaine Dependence Opioid Dependence
Keywords: Opioid Dependence Substance Related Disorders
Sponsor: Baylor College of Medicine
Start date: 2005-01-01; Completion date: 2009-12-01
Enrollment: 93 participants; Allocation: RANDOMIZED; Intervention model: PARALLEL

Brief summary:
Previous research has shown that disulfiram, a medication sometimes used for treating alcoholism, discourages cocaine use among cocaine addicts who are undergoing methadone treatment. By blocking the enzyme dopamine beta hydroxylase (DBH), disulfiram increases levels of dopamine and produces an unpleasant sense of hyperstimulation and discomfort in cocaine users. This study will evaluate the effectiveness of disulfiram in preventing drug relapse among cocaine and opiate addicts with varying inherited levels of DBH.

Detailed description:
Dopamine, a type of neurotransmitter, is the brain's "feel good" chemical. The amount of dopamine in the body may be an important factor in how cocaine addicts respond to treatment. Disulfiram, like cocaine, enhances dopamine activity. Upon taking disulfiram, subsequent intake of cocaine may elevate dopamine to excessive levels that produce extreme discomfort. DBH is an enzyme that breaks down dopamine. A particular variation in the DBH gene can affect the amount of dopamine that is released in the body. Therefore, cocaine addicts with varying DBH genes may respond differently to treatment. The purpose of this study is to compare the effectiveness of disulfiram in preventing relapse among methadone-maintained individuals addicted to both cocaine and opioids who may have different DBH genes.

This 17-week study will begin with a 2-week methadone stabilization period. Participants will then be randomly assigned to receive a daily dose of either 250 mg of disulfiram or placebo for 12 weeks, while concurrently receiving methadone treatment. All participants will stop receiving study medication at Week 14, at which point they will undergo a 4-week methadone detoxification period. Participants will report cocaine and other drug use, as well as any cocaine cravings that they experience. Cocaine levels will be monitored throughout the study with urine tests. The DBH gene of each participant will be examined to determine its specific make-up and any particular variations.

Arms: arm 1: Participants are randomly assigned to receive a daily dose of 250 mg of disulfiram for 12 weeks, while concurrently receiving methadone treatment. All participants will stop receiving study medication at week 14, at which point they will undergo a 4-week methadone detoxification period. arm 2: Participants are randomly assigned to receive a daily dose of a sugar pill to mimic the experimental drug disulfiram for 12 weeks, while concurrently receiving methadone treatment. All participants will stop receiving all medication at week 14, at which point they will undergo a 4-week methadone detoxification period.
Interventions: intervention 1: Disulfiram intervention 2: Methadone intervention 3: CBT intervention 4: Lactose
Intervention descriptions: intervention 1: Disulfiram 250 mg/day by mouth daily during study weeks 2-13. Disulfiram discontinued during study weeks 14-15. intervention 2: Initial dose 25 mg; increased by 5 mg at each subsequent daily dosing until 60 mg maintenace dose reached. intervention 3: 1-hour weekly, individual, manual-guided Cognitive Behaviorial Therapy. intervention 4: Lactose was added to both the active disulfiram and placebo doses so they tasted identical.

Protocol documents: