In this study we intend to explore whether bupropion is able to reduce smokers'''' response to cigarette-related environmental cues, and craving. Previous studies have indicated that bupropion may be able to achieve these outcomes. Therefore, we predict that smokers treated with bupropion for several weeks will show reduced reactivity to cigarette cues and craving.

Condition	Intervention	Phase
Nicotine Dependence Tobacco Dependence	Drug: Bupropion SR	Phase I

Further Study Details: 

Primary Outcomes: Cue-responsiveness at pre, post, and during treatment; Craving at pre, post, and during treatment
Secondary Outcomes: Attentional bias at pre and post treatment; Breath carbon monoxide levels at pre, post, and during treatment; Plasma cotinine levels at pre and post treatment; Puff topography measures at pre, post, and during treatment
Expected Total Enrollment:  50

Current smoking cessation pharmacotherapy paradigms ignore the over-learned behaviour associated with smoking, thus contributing to the relatively poor absolute efficacy of pharmacotherapy. Chronic nicotine use causes adaptive changes in the brain that differ from the acute effects leading to craving when smoking is stopped. This is a key element of relapse. Thus, the development of more effective treatments involves a better understanding of craving and relapse by exploring the interaction between the psychology and neurobiology of nicotine addiction. Bupropion, an amphetamine derivative, has demonstrated efficacy in smoking cessation in motivated smokers. Its’ mechanism of action is unclear but may be mediated by extinction processes. We hypothesize that bupropion will reduce cue-responsiveness and subsequent cravings in current smokers who are not consciously attempting to quit or cut down on smoking. Fifty smokers (>10 cigarettes/day) of either sex will be recruited to take either oral placebo or bupropion 150 mg twice daily for a total of 42 days. Subjects will attend bi-weekly experimental sessions where cue-responsiveness will be measured using physiological and subjective responses to a variety of neutral and smoking-related cues. Subjective effects will be measured using the Questionnaire of Smoking Urges, the Tobacco Craving Questionnaire and Visual Analog Scales. Subjects will record smoking behaviour and subjective experiences daily in a smoking diary. Outcome variables include cue responsiveness, daily diary ratings, exhaled end tidal CO levels, plasma cotinine levels, and subjective effects. Gender effects will be assessed by using sex as a covariate in the analysis. This study will provide preliminary data on pharmacotherapy-assisted extinction as a novel approach to smoking cessation.

Ages Eligible for Study:  19 Years and above,  Genders Eligible for Study:  Both

Accepts Healthy Volunteers

Criteria

Inclusion Criteria:

• Male or female
• At least 19 years of age
• Smoking at least 10 cigarettes per day for at least 2 years
• Never treated with bupropion / Zyban

Exclusion Criteria:

• Co-morbid psychiatric disorder
• History of psychotic disorder or eating disorder
• Current alcohol or substance abuse/dependence (excluding nicotine,caffeine)
• Brain injury
• Seizure disorder
• Pregnancy, lactation, or at risk of becoming pregnant
• Current regular use of psychotropic drugs
• Known allergy or sensitivity to bupropion

Please refer to this study by ClinicalTrials.gov identifier  NCT00133757

Sarwar Hussain, B.Sc. (Hon)      416-535-8501  Ext. 6346    sarwar_hussain@camh.net
Laurie Zawertailo, Ph.D.      416-535-8501  Ext. 6007    laurie_zawertailo@camh.net

Canada, Ontario
      Centre for Addiction and Mental Health, Toronto,  Ontario,  M5S 2S1,  Canada; Recruiting

Study chairs or principal investigators

Peter Selby, MD,  Principal Investigator,  Centre for Addiction and Mental Health   

Study ID Numbers:  114/2005
Last Updated:  August 23, 2005
Record first received:  August 23, 2005
ClinicalTrials.gov Identifier:  NCT00133757
Health Authority: Canada: Health Canada
ClinicalTrials.gov processed this record on 2005-08-30