Tiagabine for the Treatment of Cocaine Dependence

To assess the efficacy and safety of tiagabine in reducing cocaine use in subjects with cocaine dependence. It is hypothesized that tiagabine treatment, compared to placebo, will be associated with fewer days of cocaine use as assessed by self-report confirmed with urine assays for benzoylecgonine (BE). This is a double-blind, placebo-controlled, parallel-group design study, in which, after screening and a 2-week baseline assessment period, subjects will be equally randomly assigned to 1 of 2 treatment groups, tiagabine or matched placebo.