Combination of E-cigarettes and Varenicline for Tobacco Harm Reduction

This open-label study will explore the impact of varenicline on the process of switching from combustible cigarettes (CC) to an e-cigarette. Varenicline is currently the most efficacious single pharmacotherapy for smoking cessation, and through its actions as an agonist or partial agonist at various nicotinic acetylcholine receptor subtypes, serves to diminish the rewarding effects of cigarette smoking. Diminishing the rewarding effects of smoking might facilitate the transition from CC to e-cigarettes. On the other hand, varenicline might attenuate the rewarding effects of nicotine-containing e-cigarettes as well, which could hamper the transition. Thus, the study will provide important information about the actions of varenicline on CC as well as e-cigarettes. There is no therapeutic intent in that smokers' nicotine/tobacco dependence will not be treated; the goal is to switch from one form of nicotine/tobacco dependence (CC) to dependence on a different tobacco product (e-cigarettes).