NCT01001520

Neural Substrates in Nicotine Withdrawal

Neural Substrates of Cognitive Deficits in Nicotine Withdrawal

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 218 (actual)
• Sponsor: University of Pennsylvania · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Not accepted

Summary

This study will test the hypothesis that a medication called tolcapone (Brand Name: Tasmar) will help reduce cognitive problems that smokers experience when they quit. This study will also determine whether the benefits of this medication differ depending on a smokers' genetic background.

Detailed description

Tolcapone, an FDA-approved treatment for Parkinson's disease, improves cognitive performance in healthy controls with COMT val/val genotypes, putatively by increasing prefrontal dopamine levels. We propose a within-subject double-blind cross-over neuroimaging study of short-term (11 days) treatment with tolcapone (vs. placebo). Thirty chronic smokers (15 with val/val genotypes and 15 with val/met or met/met genotypes) will undergo blood oxygenation level dependent (BOLD) fMRI during the two medication periods: 1. after 24 hours of monitored abstinence while on tolcapone, and 2. after 24 hours of monitored abstinence while on placebo (medication order counterbalanced with at least a 10-day washout). The BOLD fMRI data will be acquired while subjects perform a working memory task (Fractal N-back), a sustained attention task (Continuous Performance Task; CPT), and a response inhibition task (Go/No-Go). The primary outcome is medication effects (within subject) on task-related BOLD activation after 24 hours of abstinence. Changes in behavioral performance and subjective symptoms will be examined in relation to brain activity changes. The proposed study will provide a critical mechanistic understanding of the role of COMT in abstinence-induced cognitive symptoms that promote smoking relapse. Information obtained in this study may further establish cognitive performance measures as endophenotypes for nicotine dependence.

Conditions

• Tobacco Use Disorder

Interventions

Type	Name	Description
DRUG	Tolcapone	Participants will be asked to take study medication each day for both 11-day study medication periods. The study medication assignments for each participant in this project is randomized and counterbalanced. This means that approximately 50% of participants will take tolcapone during the first medication period, followed by the placebo in the second medication period. Alternatively, approximately 50% of participants will take the placebo during the first medication period, followed by tolcapone during the second medication period.
DRUG	Placebo	Participants will be asked to take study medication each day for both 11-day study medication periods. The study medication assignments for each participant in this project is randomized and counterbalanced. This means that approximately 50% of participants will take tolcapone during the first medication period, followed by the placebo in the second medication period. Alternatively, approximately 50% of participants will take the placebo during the first medication period, followed by tolcapone during the second medication period.

Timeline

• Start date: 2010-01-01
• Primary completion: 2012-10-01
• Completion: 2012-10-01
• First posted: 2009-10-26
• Last updated: 2014-07-02
• Results posted: 2014-07-02

Locations

1 site across 1 country: United States