Lab Trials to Develop Medication for Cocaine Dependence
Overview
- Phase
- Phase 2
- Intervention
- Topiramate
- Conditions
- Cocaine-Related Disorders
- Sponsor
- Bankole Johnson
- Enrollment
- 25
- Locations
- 2
- Primary Endpoint
- Cocaine-induced mood changes
- Status
- Completed
- Last Updated
- 14 years ago
Overview
Brief Summary
Cocaine addiction is a serious health problem with no available medical treatment for preventing relapse. Topiramate, a medication which lowers dopamine levels, may have the ability to diminish cocaine cravings in addicts. The purpose of this study is to determine the effectiveness of topiramate in reducing cocaine's rewarding effects in individuals addicted to cocaine.
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 topiramate, a GABA-altering medication, a potential treatment for cocaine addiction. This study will evaluate the subjective, behavioral, and physiological effects of topiramate in individuals addicted to cocaine. Potential participants will initially attend a 4- to 6-hour screening session. This will include review of medical and drug histories, standardized psychological questionnaires, a physical exam, and blood collection. Eligible participants will then be admitted to the inpatient clinic. During the first day of experiment, participants will receive instructions and information about the study procedures. They will also undergo a physical exam, an electrocardiogram, standardized psychological questionnaires, and blood and urine collection. A single test dose of cocaine will be administered intravenously to all participants to ensure safety with continuation in the study. Vital signs will be monitored hourly throughout the day. The experiment will last 25 days and will enroll 24 individuals addicted to cocaine. In this three-part experiment, participants will be admitted to the inpatient clinic for an 8-day study session. Following this session, they will be discharged from the clinic for a 1-week washout phase. Participants will then return to the inpatient clinic for another 8-day study session. The two study sessions will be identical. During both sessions, participants will first receive topiramate or placebo for 4 consecutive days. While continuing to receive topiramate or placebo, participants will then also receive intravenous cocaine or placebo for 3 consecutive days.Participants will be monitored by the study physician. Electrocardiograms will be used to monitor heart activity, and blood will be drawn frequently to monitor levels of cocaine and topiramate. Participants will complete standardized questionnaires several times each day to assess mood changes and cognitive function.
Investigators
Bankole Johnson
Chair of Psychiatry and Neurobehavioral Sciences
University of Virginia
Eligibility Criteria
Inclusion Criteria
- •Meets DSM-IV-TRTM diagnostic criteria for cocaine dependence
- •Subjects must be non-treatment seeking, cocaine-dependent or cocaine-abusing individuals who report taking cocaine at least once a month
- •In generally good health as confirmed by medical history, physical examination, electrocardiogram, laboratory screening tests, and vital signs
- •Must be able to take oral medication, adhere to the medication regimens, and be willing to return to the clinic for regular study visits
- •Must be able to read and understand all instructions, rating scales, and questionnaires in English
- •Must be willing to stay overnight at the University Clinical Psychopharmacology Laboratory (UCPL)
- •Must comply with the alcohol, tobacco, and drug-free environment regulations at the UCPL
- •If female, must be postmenopausal for at least 1 year, surgically sterile, or willing to use contraception throughout the study
Exclusion Criteria
- •History of mental illness, other than cocaine or nicotine dependence
- •History of mental retardation or neuropsychological functioning greater than 1.5 standard deviation below expected rang.
- •Clinically significant abnormalities found on the electrocardiogram
- •History of hypertension (blood pressure greater than 140/90 mm Hg) or systolic hypotension (blood pressure less than 90/75 mm Hg)
- •Resting pulse rate of greater than 90 beats per minute
- •Cerebrovascular accident or transient ischemic attack
- •Ischemic heart disease or heart attack
- •Symptomatic coronary artery disease or peripheral vascular disease
- •Cancer or history of cancer within the 5 years of study entry (other than basal cell carcinoma)
- •Kidney disease and/or impaired kidney function, as defined by an estimated creatinine clearance of 60 mL per minute
Arms & Interventions
Topiramate
Intervention: Topiramate
Placebo
Intervention: Topiramate
Outcomes
Primary Outcomes
Cocaine-induced mood changes
Time Frame: measured throughout cocaine and topiramate testing sessions
Effects of topiramate on cognitive function
Time Frame: measured throughout cocaine and topiramate testing sessions
Drug safety
Time Frame: measured throughout cocaine and topiramate testing sessions
Cardiovascular response to cocaine (measured throughout cocaine and topiramate testing sessions)
Time Frame: measured throughout cocaine and topiramate testing sessions
Secondary Outcomes
- Physiological response (measured throughout cocaine and topiramate testing sessions)(measured throughout cocaine and topiramate testing sessions)