Conditions: Tobacco Dependence
Keywords: tobacco nicotine smoking reward reinforcement craving cues conditioned stimuli cue reactivity
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 163
Healthy volunteers: yes

Brief summary:
The purpose of this study was to find out how varenicline works to help people quit smoking. Varenicline, also known as Chantix™, is an U.S. Food and Drug Administration (FDA) approved medication that has been shown to help people quit smoking. This study was trying to evaluate whether varenicline would change the response to smoking and the desire for cigarettes when compared to an inactive placebo control. This was not a quit smoking treatment study, and participants were not asked or required to stop smoking while in this study.

Detailed description:
We proposed the following primary hypotheses:

1. Tonic (i.e., non-cue-provoked) craving levels would be lower in participants receiving varenicline versus placebo.
2. Cue-provoked cravings (self-report and physiological responding) would be lower in participants receiving varenicline versus placebo. (Secondary indices of craving include heart rate and skin conductance.)
3. The two primary indices of nicotine reward/reinforcement (mCEQ and choice index) would be lower in participants receiving varenicline versus placebo. (Secondary indices of nicotine reinforcement include smoking topography variables.)

A final sample of 100 non-treatment seeking daily smokers were recruited from the Tampa-St. Petersburg-Clearwater Metropolitan Area via paid advertisements in, and press releases to, local newspapers, as well as targeted outdoor advertising via flyers (e.g., on public transportation).

Following the screening session, participants were randomly assigned to receive either varenicline or placebo medication.

Arms:
arm 1: For participants in the varenicline group, the medication doses followed the recommended dose schedule for the first 15 days of treatment: 0.5 mg once a day on days 1-3, 0.5 mg twice a day on days 4-7, and 1 mg twice a day on days 8-15. arm 2: Participants in this group received a placebo instead of medication. The placebo was taken once a day on days 1-3, twice a day on days 4-15.

Interventions: intervention 1: varenicline intervention 2: placebo
Intervention descriptions: intervention 1: Participants in this group received varenicline according to the schedule in the Arm Description. intervention 2: Participants in this group received a placebo and did not receive any active medication according to the schedule in the Arm Description.

Protocol document: