Caffeine and Cocaine
This study is being done to find out if medicines that affect a neurotransmitter (chemical messenger) in the brain called adenosine improve behavioral problems that are related to drug abuse. Another purpose of the study is to find out how genes related to adenosine change how people respond to these medicines. More information about how these medicines change behaviors may be helpful to come up with new treatments for drug abuse.
|Study Design:||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
|Official Title:||Experiment 1: Adenosine Receptor A2A Antagonists and Cocaine Dependence|
- impulsivity [ Time Frame: 3 weeks of treatment ] [ Designated as safety issue: No ]
- cocaine positive urines [ Time Frame: 3 weeks of treatment ] [ Designated as safety issue: No ]
- cue reactivity [ Time Frame: 3 weeks of treatment ] [ Designated as safety issue: No ]
|Study Start Date:||April 2008|
|Study Completion Date:||October 2011|
|Primary Completion Date:||July 2011 (Final data collection date for primary outcome measure)|
300 mg for 7 days; then 600 mg for 7 days; then 900 mg for 7 days; followed by a 3 day taper. all dosing three times per day
Other Name: Vivarin
Placebo Comparator: 2
3 times per day
Other Name: Placebo
Aim 1. To characterize the behavioral and subjective effects of acute caffeine administration in cocaine-dependent subjects, using laboratory measures of impulse control, drug discrimination (with d-amphetamine as the training dose), and subjective effects.
Hypotheses related to Aim 1:
- Subjects will show decreases in impulsivity (delay to reward and response inhibition) after acute oral doses of caffeine compared to placebo.
- Subjects will show some stimulant-like subjective effects following acute oral doses of caffeine, but not the euphoric effects that would predict abuse potential.
- Following training doses of placebo and 20 mg d-amphetamine, oral doses of caffeine will be discriminated as being different than 20 mg d-amphetamine and different from placebo.
Aim 2. To determine the effect of a 2-week trial of oral caffeine on laboratory measures of impulsivity and cue reactivity in cocaine dependent subjects.
Hypothesis related to Aim 2:
- Daily caffeine (600 - 900 mg) treatment will decrease impulsivity (delay to reward and response inhibition) compared to placebo.
- Daily caffeine (600 - 900 mg) treatment will decrease cocaine related cue reactivity compared to placebo.
Secondary Aim 1. To examine the effect of 2-weeks of treatment with caffeine on cocaine use in cocaine dependent subjects.
Secondary hypothesis 1: Cocaine dependent subjects treated with caffeine will show a significant reduction in cocaine positive urine drug screens compared with cocaine dependent subjects treated with placebo.
Secondary Aim 2. To examine the relationship between gene polymorphisms for the A2A receptor gene and behavioral effects of caffeine Secondary hypothesis 2: Genetic variation in the adenosine A2A receptor gene (ADORA2A) will be associated with the behavioral effects of caffeine.
|United States, Texas|
|The University of Texas Health Science Center, Houston|
|Houston, Texas, United States, 77030|
|Principal Investigator:||Frederick G Moeller, MD||The University of Texas Health Science Center, Houston|