Official Title: “Double-Blind, Randomized, Placebo- Controlled Trial of Vigabatrin for Short Term Abstinence From Cocaine in Cocaine Dependent Parolees”

The primary objective of this study is to assess the efficacy of vigabatrin for the treatment of cocaine dependence, based on the twice-weekly qualitative urine toxicologies for cocaine.

Based on two prior unblinded human studies and 15 years of animal studies, this 100 subject double- blind, randomized study is designed to show if with vigabatrin treatment but not placebo, even non-hospitalized cocaine dependent individuals with ready access to cocaine will become cocaine abstinent if they are self motivated to stop their cocaine habit. To accomplish this, cocaine dependent subjects will be randomly assigned to either a placebo or vigabatrin treatment group and treated for a nine week period. The primary hypothesis is that as compared to the placebo arm, the vigabatrin treatment arm will show a significant increase in the number of subjects who are abstinent for the final 3 weeks of the study.

Study Type: Interventional

Study Design: Treatment, Randomized, Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Placebo Control, Parallel Assignment, Efficacy Study

Study Primary Completion Date: November 2007

Intervention(s) in this Clinical Trial

• Drug: Vigabatrin
  • crystalline drug dissolved in orange juice, dosage escalates from 500 mg twice daily to 1.5 g twice daily over a 3 week period. This dose is maintained for 4 weeks and then tapered to zero over the next two weeks
• Drug: Placebo
  • orange juice is administered twice daily in containers indistinguishable from the treatment arm.
• Behavioral: Group therapy
  • Participants attend group sessions once a week

Arms, Groups and Cohorts in this Clinical Trial

• Active Comparator: A
  • Subjects will receive vigabatrin in escalating doses to 3 grams per day over three weeks, continued for 4 weeks and then tapered to zero over the next 2 weeks.
• Placebo Comparator: B
  • Orange juice and administration identical to Arm A.

Primary Measures

• Three consecutive weeks of negative urine tests (benzoyl ecgonine) for cocaine use (no slips allowed).
  • Time Frame: These must be the last three weeks (7,8,9) of the trial.
    Safety Issue?: No

Secondary Measures

• 3 consecutive weeks of negative urines (one slip allowed)
  • Time Frame: Last 3 weeks (7,8,9) of the trial
    Safety Issue?: No
• cocaine craving
  • Time Frame: Weeks 1, 5,9
    Safety Issue?: No

Inclusion Criteria:

• In order to participate in the study, subjects must
• Be at least 18 years of age and no older than 55 years of age.
• Weigh more than 100 pounds.
• Have a DSM-IV diagnosis of cocaine dependence.
• Be seeking treatment for cocaine dependence.
• Have a urine sample positive for qualitative cocaine toxicology at initial screening.
• Have the ability to understand, and having understood, provide written informed consent to comply with the treatment protocol.
• Have a history and brief physical examination that demonstrate no clinically significant contraindication for participating in the study, in the judgment of the admitting physician and the Principal Investigator.
• Have normal, or, if necessary, corrected visual acuity, visual fields, and normal fundoscopy findings

Exclusion Criteria:

• In order to participate in the study, subjects must not:
• Meet DSM-IV criteria for current dependence on any psychoactive substance other than cocaine, alcohol, nicotine, or marijuana or physiological dependence on alcohol requiring medical detoxification.
• Have neurological or psychiatric disorders such as: psychosis, bipolar illness, major depression, organic brain disease, dementia, any disorder which would require ongoing treatment or which would make study agent compliance difficult, history of suicide attempts assessed and/or current suicidal ideation/plan.
• Have serious medical illnesses or other potentially life threatening or progressive medical illness other than addiction that may compromise subject safety or study conduct.
• Have a history of traumatic head injury.
• Be mandated by a court to obtain treatment for cocaine dependence.
• Have been treated for cocaine addiction, or abstained from cocaine use for a significant period, within the 6 months preceding screening.
• Be unable to complete the study protocol because of probable incarceration or relocation from the clinical area.
• Have AIDS (although AIDS is an exclusion criterion, a positive antibody titer to HIV is not).
• Have active syphilis that has not been treated or refuse treatment for syphilis
• Have a history of neuroleptic malignant syndrome.
• Have known or suspected hypersensitivity to vigabatrin or any other GABAergic drug.
• Have received a drug with known potential for toxicity to a major organ system within 30 days prior to study entry (e.g., isoniazid, methotrexate).
• Have participated in any experimental study within 4 weeks, or participated in any clinical trial utilizing vigabatrin.
• Be pregnant or lactating.
• Have any clinically significant abnormal laboratory value.
• Have had electroconvulsive therapy with the 3 months preceding screening.
• Have had any opiate-substitutes (methadone, LAAM, buprenorphine) within 2 months preceding screening.
• Have a history of i.v. cocaine (or other psychoactive drug) use within 2 months preceding screening.
• Have a current or past history of seizure disorder, including alcohol- or stimulant related seizure, febrile seizure, or significant family history of idiopathic seizure disorder.
• Have a visual field defect, or factor predisposing to visual field defects, including glaucoma, severe myopia, retinal disorder, cataracts, diabetes or uncontrolled hypertension.
• Have my illness, condition, and use of medications, in the opinion of the Principal Investigator and the admitting physician, which would preclude safe or successful completion of the study.
• Be using vigabatrin or any medication that could interact adversely with vigabatrin administration, based on the longest time interval of A or B below:
• A) Five half-lives of other medication or active metabolite(s), whichever is longer;
• B) Two weeks.
• Be lactose intolerant.

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: 55 Years

Are Healthy Volunteers Accepted for this Clinical Trial?: No

Lead Sponsor: New York University School of Medicine

Overall Clinical Trial Officials and Contacts

Jonathan D Brodie, Ph.D., M.D. Principal Investigator New York University School of Medicine  

Information obtained from ClinicalTrials.gov on August 29, 2008

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00527683

Study ID Number: H06-152

ClinicalTrials.gov Identifier: NCT00527683

Health Authority: United States: Institutional Review Board