Overview Effects of Varenicline on Brain Activity During Nicotine Abstinence Status: Completed Trial end date: 2008-08-01 Target enrollment: Participant gender: Summary This project aims to define mechanisms through which varenicline might be an effective smoking cessation medication. Phase: N/A Details Lead Sponsor: University of PennsylvaniaCollaborators: National Cancer Institute (NCI)PfizerTreatments: Varenicline