A double-blind, placebo-controlled trial of tiagabine for the treatment of cocaine dependence.

BACKGROUND: The potential efficacy of tiagabine for treating cocaine dependence is suggested by both pre-clinical research and two small clinical trials. METHOD: One hundred and forty one participants who met DSM-IV criteria for cocaine dependence were enrolled into this 12-week, double blind, placebo controlled outpatient trial. Participants received either tiagabine (20 mg/day) or matching placebo. All participants received 1h of manualized individual cognitive behavioral therapy on a weekly basis. Outcome measures included cocaine use as determined by self-report confirmed with urine benzoylecgonine (BE) results, and qualitative and quantitative urine toxicology measures. Safety measures included adverse events, EKGs, vital signs, and laboratory tests. RESULTS: Seventy-nine participants (i.e., 56%) completed the 12-week trial. The safety results suggest that tiagabine was safe and generally well tolerated by the participants. Participants in both groups improved significantly on cocaine craving and global functioning, with no significant differences between the groups. There were no significant changes in cocaine use as measured by self-report confirmed by urine BE or by quantitative urine toxicology results. Qualitative urine toxicology results suggest a possible weak effect for tiagabine in reducing cocaine use. CONCLUSION: These results suggest that tiagabine, at a dose of 20 mg/day, did not have a robust effect in decreasing cocaine use.

A double-blind, placebo-controlled trial of reserpine for the treatment of cocaine dependence.

BACKGROUND: Cocaine's increase of dopamine is strongly associated with its reinforcing properties and, thus, agents that reduce dopamine have received much attention as candidate cocaine-dependence treatments. The potential efficacy of reserpine, a dopamine depletor, for treating cocaine dependence is suggested by both pre-clinical research and a small clinical trial. METHOD: One hundred and nineteen participants who met DSM-IV criteria for cocaine dependence were enrolled into this 12-week, double-blind, placebo-controlled outpatient trial. Participants received either reserpine (0.5 mg/day) or matching placebo. All participants received 1h of manualized individual cognitive behavioral therapy on a weekly basis. Outcome measures included cocaine use as determined by self-report confirmed with urine benzoylecgonine results, cocaine craving, addiction severity index scores, and clinical global impression scores. Safety measures included adverse events, EKGs, vital signs, laboratory tests, and the Hamilton Depression Inventory. RESULTS: Seventy-nine participants (i.e., 66%) completed the 12-week trial. The safety results suggest that reserpine was safe and well tolerated by the participants. The efficacy measures indicated no significant differences between reserpine and placebo. CONCLUSION: These results do not support the efficacy of reserpine as a cocaine-dependence treatment.

Methylphenidate and cocaine: a placebo-controlled drug interaction study.

Up to thirty percent of cocaine addicted individuals may meet diagnostic criteria for Attention-Deficit/Hyperactivity Disorder (ADHD). Methylphenidate (MPH) is a highly effective and commonly used treatment for ADHD but, like cocaine, is a cardiovascular and central nervous system stimulant with the potential to cause toxicity at high doses. The present study was undertaken to investigate the likelihood of a toxic reaction in individuals who use cocaine while concurrently taking MPH. Seven non-treatment seeking cocaine-dependent individuals completed this placebo-controlled, crossover study with two factors: Medication (placebo, 60 mg MPH, 90 mg MPH) and Infusion (saline, 20 mg cocaine, 40 mg cocaine). Physiological measures included vital signs, adverse events, and electrocardiogram. Subjective response was measured with visual analog scale (VAS) ratings of craving and drug effect. Cocaine pharmacokinetic parameters were calculated for each participant at each drug combination, using a non-compartmental model. MPH was well tolerated, did not have a clinically significant impact on cocaine's physiological effects, and decreased some of the positive subjective effects of cocaine. MPH did not significantly alter the pharmacokinetics of cocaine. The study results suggest that MPH at the doses studied can likely be used safely in an outpatient setting with active cocaine users.

A medication screening trial evaluation of reserpine, gabapentin and lamotrigine pharmacotherapy of cocaine dependence.

AIMS: To conduct a preliminary evaluation of the safety and efficacy of reserpine, gabapentin or lamotrigine versus an unmatched placebo control as a treatment for cocaine dependence. DESIGN: A 10-week out-patient study using the Cocaine Rapid Efficacy and Safety Trial (CREST) study design. SETTING: The study was conducted at the Cincinnati Medication Development Research Unit (MDRU). PARTICIPANTS: Participants met Diagnostic and Statistical Manual version IV (DSM-IV) criteria for cocaine dependence. Sixty participants were enrolled, with 50 participants completing the final study measures. INTERVENTION: The targeted daily doses of medication were reserpine 0.5 mg, gabapentin 1800 mg and lamotrigine 150 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, electrocardiograms (ECGs), vital signs and laboratory tests. FINDINGS: Subjective measures of cocaine dependence indicated significant improvement for all study groups. Urine BE results indicated a significant improvement for the reserpine group (P < 0.05) 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. The medications appeared to be tolerated well. CONCLUSIONS: The present findings suggest that reserpine may be worthy of further study as a cocaine dependence treatment.

A placebo-controlled screening trial of tiagabine, sertraline and donepezil as cocaine dependence treatments.

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.

An open-label pilot study of methylphenidate in the treatment of cocaine dependent patients with adult attention deficit/hyperactivity disorder.

A multi-site, open-label study of methylphenidate for treating patients with comorbid diagnoses of attention deficit/hyperactivity disorder and cocaine dependence was performed. Forty-one participants, who met DSM-IV criteria for adult attention deficit/hyperactivity disorder and cocaine dependence, were enrolled into this ten week outpatient study. The targeted total daily dose of methylphenidate was 60 mg (20 mg TID). Participants received individual substance abuse therapy throughout the trial. Safety measures included adverse events, vital signs, and electrocardiograms. Methylphenidate's efficacy was assessed by both objective and subjective measures. Seventy percent of the participants completed final study measures. Safety measures indicated that methylphenidate was well tolerated by the participants. Subjective efficacy measures suggested that participants evidenced improvement in both cocaine dependence and adult attention deficit/hyperactivity disorder symptoms. Quantitative benzoylecgonine indicated that only those participants categorized as being compliant showed improvement. A double-blind, placebo-controlled study of methylphenidate for this population may be warranted.