The Effects of GABA Enhancing Medications on Individuals Addicted to Cocaine - 3

July 7, 2015 updated by: Mehmet Sofuoglu, Yale University

The Effects of GABA Medications on Cocaine Responses in Humans

Gamma-aminobutyric acid (GABA) is a type of neurotransmitter, which is a chemical that transmits information within and from the brain to all parts of the body. By lowering the level of another neurotransmitter called dopamine, GABA may have the ability to diminish cocaine cravings in addicts. The purpose of this study is to gather information on the interaction between cocaine and selected GABA enhancing medications in individuals addicted to cocaine. This may lead to future clinical studies using GABA medications to treat cocaine addiction.

Study Overview

Status

Terminated

Conditions

Intervention / Treatment

Detailed Description

GABA is an inhibitory neurotransmitter that is found primarily in the brain. High GABA levels result in low levels of dopamine, another neurotransmitter that is the brain's "feel good" chemical and which plays a primary role in cocaine drug addiction. Cravings for cocaine can be reduced by lowering dopamine levels. This makes GABA-altering medications a potential treatment for cocaine addiction. This study will involve five GABA enhancing medications: tiagabine, topiramate, valproic acid, baclofen, and progesterone. The purpose of the study is to evaluate the interaction between GABA medications and cocaine in terms of safety and craving responses. In turn, these findings may guide future cocaine pharmacotherapy trials.

This 6-day inpatient study will begin with an orientation session to familiarize participants with study procedures. The evening of Day 1, all participants will receive placebo medication. On Days 2 through 4, participants will receive one of five GABA medications. The GABA medications will be given in gradually increasing doses to attain therapeutic levels while maintaining safety and minimizing side effects. Three experimental cocaine sessions will take place; one while the participants are receiving the placebo medication and two while the participants are receiving the GABA medications. During these sessions, cocaine will be administered intravenously in three increasing doses, each separated by 30-minute intervals. This will allow the participants' subjective and physiological responses during cocaine administration to return to baseline levels before the next dose. Blood will be drawn after each dose; heart rate, blood pressure, and an ECG will be monitored throughout the sessions. At the end of each session, questionnaires will be administered to assess the effects of cocaine and related mood states, as well as allow the participants to report any adverse events, depression, craving, or withdrawal symptoms.

This study is now closed and published.

Study Type

Interventional

Enrollment (Actual)

72

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Connecticut
      • West Haven, Connecticut, United States, 06516
        • VA Connecticut Healthcare System

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 45 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Meets DSM-IV criteria for cocaine dependence
  • History of smoked or intravenous cocaine use on average of at least once a week over a 6 month period
  • Positive urine test for cocaine
  • No current medical problems
  • Normal electrocardiogram
  • If female, willing to use contraception throughout the study

Exclusion Criteria:

  • Seeking treatment for cocaine dependence
  • Current major psychiatric illness, including mood disorder, psychotic disorder, or anxiety disorder
  • Current dependence on alcohol or any drugs other than cocaine or nicotine
  • History of major medical illness, including liver disease, suspected or known cancer, thrombophlebitis, or other medical conditions that are considered unsafe for study participants by the investigator
  • Known allergy to study medications
  • Pregnant or breastfeeding

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: pregabalin
pregabalin compared to placebo
Drug: Pregabalin
pregabalin compared to placebo
Other Names:
  • lyrica
Placebo Comparator: Placebo
Placebo compared to pregabalin
Drug: placebo
sugar pill compared to pregabalin
Other Names:
  • sugar pill

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Analog rating scale for drug effects; measured during each experimental session
Time Frame: one week
one week
Physiological response to cocaine; measured during each experimental session
Time Frame: one week
one week

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Yale University

Collaborators

National Institute on Drug Abuse (NIDA)

Investigators

  • Principal Investigator: Thomas R Kosten, MD, Yale University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

September 1, 2004

Primary Completion (Actual)

September 1, 2006

Study Completion (Actual)

September 1, 2006

Study Registration Dates

First Submitted

September 1, 2005

First Submitted That Met QC Criteria

September 1, 2005

First Posted (Estimate)

September 2, 2005

Study Record Updates

Last Update Posted (Estimate)

July 8, 2015

Last Update Submitted That Met QC Criteria

July 7, 2015

Last Verified

July 1, 2015

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • NIDA-18197-3
  • DPMC (Other Identifier: NIDA)
  • P50DA018197-03 (U.S. NIH Grant/Contract)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe