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OpenTrials
Completed

NCT Number: NCT02949934

Effects of Cortical Dopamine Regulation on Drinking, Craving, and Cognitive Control

The purpose of this study is to determine whether the catechol-O-methyltransferase (COMT) inhibitor tolcapone, relative to placebo, reduces alcohol drinking and alcohol cue-elicited brain activation and increases brain activation associated with cognitive control as a function of a participant's genotype at a polymorphism in the COMT gene.

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Key information

Age range

21 year–40 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Medical University of South Carolina

Charleston, South Carolina, 29403, United States

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age 21-40 (to focus on an age group still on a trajectory of increasing alcohol consumption).
  • Meets Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) criteria for current Alcohol Use Disorder.
  • Currently not engaged in, and does not want treatment for, alcohol-related problems.
  • Able to read and understand questionnaires and informed consent.
  • Lives within 50 miles of the study site.
  • Able to maintain abstinence from alcohol for two days (without the aid of detoxification medications), as determined by self report and breathalyzer measurements.

Exclusion criteria

  • Current DSM-5 diagnosis of any other substance use disorder except Nicotine Use Disorder.
  • Any psychoactive substance use (except marijuana and nicotine) within the last 30 days, as indicated by self-report and urine drug screen. For marijuana, no use within the last seven days by verbal report and negative (or decreasing) urine tetrahydrocannibinol (THC) levels.
  • Current DSM-5 Axis I diagnosis, including major depression, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, bipolar affective disorder, schizophrenia, dissociative disorders, eating disorders, or any other psychotic or organic mental disorder.
  • Current suicidal ideation or homicidal ideation.
  • Need for maintenance or acute treatment with any psychoactive medication, including antiepileptic medications.
  • Currently taking medication known to affect alcohol intake (e.g., disulfiram, naltrexone, acamprosate, topiramate).
  • History of severe alcohol withdrawal (e.g., seizure, delirium tremens), as evidenced by self-report and assessment with Clinical Institute Withdrawal Assessment for Alcohol-Revised (CIWA-Ar).
  • Clinically significant medical problems such as cardiovascular, renal, gastrointestinal, or endocrine problems that would impair participation or limit medication ingestion.
  • Past alcohol-related medical illness, such as gastrointestinal bleeding, pancreatitis, or peptic ulcer.
  • Current or past hepatocellular disease, as indicated by verbal report or elevations of alanine aminotransferase (ALT) or aspartate aminotransferase (AST) greater than the upper limit of the normal range at screening.
  • Females of childbearing potential who are pregnant (by urine human chorionic gonadotropin), nursing, or who are not using a reliable form of birth control.
  • Current charges pending for a violent crime (not including drinking while intoxicated).
  • Lack of a stable living situation.
  • Presence of ferrous metal in the body, as evidenced by metal screening and self-report.
  • Severe claustrophobia or morbid obesity that preclude placement in the MRI scanner.
  • History of head injury with > 2 minutes of unconsciousness.

Treatment and study plan

Tolcapone

Drug

Other names: Tasmar

Placebo

Drug

Primary outcomes

  1. Total Number of Standard Drinks Per Day Consumed During Natural (Usual Environment) Conditions

    Time frame: Days 1-6 of study medication ingestion

    Number of standard alcoholic drinks per day that participants reported consuming, as assessed by the Timeline Follow-back method.

  2. Total Number of Drinks Under Controlled Conditions (Bar Lab)

    Time frame: 2 hours during the alcohol challenge procedure

    Total number of drinks, out of 8 possible, that participants chose to consume in the bar laboratory after receipt of a priming drink, targeted by sex and body weight to produce a breath alcohol concentration of 0.03 g/dL. Each of the drinks that participants chose to consume was targeted to produce a breath alcohol concentration of 0.015 g/dL. Participants were given a "bar credit" of $16 with which to "purchase" drinks, at the cost of $2/drink, and were told that any money they did not spend would be given to them the following day.

Other outcomes

  1. Cognitive-control-associated Brain Activation (fMRI)

    Time frame: 7 days--change between baseline and scan on day 7

    Magnitude of change between baseline and day 7 scan in the BOLD signal in the right inferior frontal gyrus to spatial working memory

  2. Alcohol Cue-elicited Brain Activation (fMRI)

    Time frame: 7 days--change between baseline and scan on day 7

    Magnitude of change between baseline and day 7 scan in the right inferior frontal gyrus blood oxygenation level dependent (BOLD) signal to alcohol cues, relative to neutral beverage cues (alcohol cue reactivity task described in Schacht et al., 2013, Neuropsychopharmacology)

Sponsors and collaborators

Lead sponsor

Medical University of South Carolina

Other

Collaborators

  • National Institute on Alcohol Abuse and Alcoholism (NIAAA)

Registry information

Important dates

Study start
2016
Primary completion
2021
Study completion
2021
First posted
Oct 31, 2016
Registry last updated
Jun 9, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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