The study is a randomized crossover trial. Current smokers will be randomized to session order and complete a standardized 10-puff bout (5 minutes) followed by a 60-minute ad libitum session with each product (usual brand cigarette, e-cigarette, heat-not-burn). Throughout each visit, blood will be collected for nicotine analysis via an IV catheter placed in the patient's arm. Blood samples will be aliquoted into two separate vials. One will be analyzed for the current study and one will be placed in a biospecimen repository if participant provides consent for biorepository. Puff topography will be collected passively throughout the session to measure puffing patterns. Participants will complete self-report measures of nicotine withdrawal and craving. Finally, breath samples will be collected to measure changes in exhaled carbon monoxide, a potent lung toxicant, pre- and post-product use. At the final visit, participants will complete a behavioral economics concurrent choice task (see below for description) to behaviorally measure their decisions regarding use of e-cigarettes or HNB products in place of cigarettes. Finally, participants will be contacted by phone 6 months following the conclusion of visit 3 (or study discontinuation) to complete a phone survey. The objective of this survey is to assess for ongoing use of study products and is part of safety monitoring. We have no hypotheses related to the follow-up.
The study is a randomized crossover trial. Current smokers will complete a session with each product: usual brand cigarette, e-cigarette, and heat-not-burn. The objective of this survey is to assess for ongoing use of study products and is part of safety monitoring.