Six-month trial of bupropion with contingency management for cocaine dependence in a methadone-maintained population.
ABSTRACT No effective pharmacotherapies exist for cocaine dependence, although contingency management (CM) has demonstrated efficacy.
To compare the efficacy of bupropion hydrochloride and CM for reducing cocaine use in methadone hydrochloride-maintained individuals.
This 25-week, placebo-controlled, double-blind trial randomly assigned participants to 1 of 4 treatment conditions: CM and placebo (CMP), CM and 300 mg/d of bupropion hydrochloride (CMB), voucher control and placebo (VCP), or voucher control and bupropion (VCB).
Outpatient clinic at the Veterans Affairs Connecticut Healthcare System.
A total of 106 opiate-dependent, cocaine-abusing individuals.
All study participants received methadone hydrochloride (range, 60-120 mg). Participants receiving bupropion hydrochloride were given 300 mg/d beginning at week 3. In the CM conditions, each urine sample negative for both opioids and cocaine resulted in a monetary-based voucher that increased for consecutively drug-free urine samples during weeks 1 to 13. Completion of abstinence-related activities also resulted in a voucher. During weeks 14 to 25, only completion of activities was reinforced in the CM group, regardless of sample results. The voucher control groups received vouchers for submitting urine samples, regardless of results, throughout the study.
Thrice-weekly urine toxicologic test results for cocaine and heroin.
Groups did not differ in baseline characteristics or retention rates. Opiate use decreased significantly, with all treatment groups attaining equivalent amounts of opiate use at the end of the study. In the CMB group, the proportion of cocaine-positive samples significantly decreased during weeks 3 to 13 (P<.001) relative to week 3 and remained low during weeks 14 to 25. In the CMP group, cocaine use significantly increased during weeks 3 to 13 (P<.001) relative to week 3, but then cocaine use significantly decreased relative to the initial slope during weeks 14 to 25 (P<.001). In contrast, by treatment end, the VCB and VCP groups showed no significant improvement in cocaine use.
These findings suggest that combining CM with bupropion for the treatment of cocaine addiction may significantly improve outcomes relative to bupropion alone.
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ABSTRACT: Dual dependence on opiate and cocaine occurs in about 60% of patients admitted to methadone maintenance and negatively impacts prognosis (Kosten et al. 2003. Drug Alcohol Depend. 70, 315). Topiramate (TOP) is an antiepileptic drug that may have utility in the treatment of cocaine dependence because it enhances the GABAergic system, antagonizes the glutamatergic system, and has been identified by NIDA as one of only a few medications providing a "positive signal" warranting further clinical investigation. (Vocci and Ling, 2005. Pharmacol. Ther. 108, 94). In this double-blind controlled clinical trial, cocaine dependent methadone maintenance patients (N=171) were randomly assigned to one of four groups. Under a factorial design, participants received either TOP or placebo, and monetary voucher incentives that were either contingent (CM) or non-contingent (Non-CM) on drug abstinence. TOP participants were inducted onto TOP over 7 weeks, stabilized for 8 weeks at 300mg daily then tapered over 3 weeks. Voucher incentives were supplied for 12 weeks, starting during the fourth week of TOP induction. Primary outcome measures were cocaine abstinence (Y/N) as measured by thrice weekly urinalysis and analyzed using Generalized Estimating Equations (GEE) and treatment retention. All analyses were intent to treat and included the 12-week evaluation phase of combined TOP/P treatment and voucher intervention period. There was no significant difference in cocaine abstinence between the TOP vs. P conditions nor between the CM vs. Non-CM conditions. There was no significant TOP/CM interaction. Retention was not significantly different between the groups. Topiramate is not efficacious for increasing cocaine abstinence in methadone patients.Drug and alcohol dependence 04/2014; · 3.60 Impact Factor
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ABSTRACT: Background Developing personalized treatments for cocaine dependence remains a significant clinical challenge. Positron emission tomography (PET) has shown that the [11 C]raclopride signal in the ventral striatum is associated with treatment success in a positively reinforced contingency management program. The present study investigates whether this signal can be used to predict treatment outcome at an individual level. Methods Predictive models were developed using PET signals from 5 regions of the striatum and follow-up data in 24 patients, and evaluated using cross-validation. Results The ventral striatal PET signal alone can predict individual treatment response with a substantial degree of accuracy (cross-validated correct rate = 82%). Incorporating information from other regions-of-interest (ROIs) in the striatum does not improve predictive performance, except for a small improvement with adding the posterior caudate. The addition of baseline demographic variables, including baseline severity measures, does not improve predictive performance. On the other hand, early treatment response and motivation, reflected by cumulative clinic attendance, performs as well as the PET signal (83%) by week 3 in the 24-week study. The combined model with both PET signals and cumulative clinic attendance demonstrates a significant improvement of performance, peaking at 96% during week 3 of the trial. Conclusions These results suggest that a multimodal model can predict treatment success in cocaine dependence at an individual level, and pose hypotheses for the underlying neural circuitry mechanisms responsible for individual variations in treatment outcome.Comprehensive Psychiatry 11/2014; · 2.26 Impact Factor
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ABSTRACT: In the treatment of addictions, the gap between the availability of evidence-based therapies and their limited implementation in practice has not yet been bridged. Two empirically validated behavioral therapies, contingency management (CM) and cognitive behavioral therapy (CBT), exemplify this challenge. Both have a relatively strong level of empirical support but each has weak and uneven adoption in clinical practice. This review highlights examples of how barriers to their implementation in practice have been addressed systematically, using the Stage Model of Behavioral Therapies Development as an organizing framework. For CM, barriers such as cost and ideology have been addressed through the development of lower-cost and other adaptations to make it more community friendly. For CBT, barriers such as relative complexity, lack of trained providers, and need for supervision have been addressed via conversion to standardized computer-assisted versions that can serve as clinician extenders. Although these and other modifications have rendered both interventions more disseminable, diffusion of innovation remains a complex, often unpredictable process. The existing specialty addiction-treatment system may require significant reforms to fully implement CBT and CM, particularly greater focus on definable treatment goals and performance-based outcomes.Annals of the New York Academy of Sciences 09/2014; · 4.38 Impact Factor