Aims: To conduct a preliminary evaluation of the safety and efficacy of tiagabine, sertraline or donepezil versus an unmatched placebo control as a treatment for cocaine dependence.
Design: A 10-week out-patient study was conducted using the Cocaine Rapid Efficacy and Safety Trial (CREST) study design.
Setting: This study was conducted at the Cincinnati Medication Development Research Unit (MDRU) and at an affiliated site in Dayton, Ohio.
Participants: Participants met Diagnostic and Statistical Manual version IV (DSM-IV) criteria for cocaine dependence. Sixty-seven participants were enrolled with 55 completing final study measures.
Intervention: The targeted daily doses of medication were tiagabine 20 mg, sertraline 100 mg and donepezil 10 mg. All participants received 1 hour of manualized individual cognitive behavioral therapy on a weekly basis.
Measurements: Primary outcome measures of efficacy included urine benzoylecgonine (BE) level, Cocaine Clinical Global Impression Scale-Observer and self-report of cocaine use. Safety measures included adverse events, ECGs, vital signs and laboratory tests.
Findings: Subjective measures of cocaine dependence indicated significant improvement for all study groups. Generalized estimating equations analysis indicated that the tiagabine group showed a trend toward a significant decrease in urine BE level from baseline to weeks 5-8 (P = 0.10) and non-significant changes for the other study groups. No pattern of physical or laboratory abnormalities attributable to treatment with any of the medications was identified. There were three serious adverse events reported, none of which were related to study procedures.
Conclusions: The present findings suggest that tiagabine may be worthy of further study as a cocaine dependence treatment.