Nicotine pharmacokinetic (PK) studies are an important tool in developing our understanding of actual nicotine delivery into the body from electronic cigarettes and other nicotine-containing products. Furthermore, data from such studies may potentially be required as part of a regulatory package, particularly as one aspect of an abuse liability assessment of a novel product.

This presentation (Part 1 of 2) will outline the study designs for two nicotine PK studies in which we examined blood nicotine levels during acute clinical use periods in subjects smoking cigarettes and using e-cigarettes. The first study (ISRCTN74070762; Belfast, U.K.) compared blood nicotine levels in 24 smokers using closed-system modular e-cigarettes according to a defined puffing schedule, with those seen when subjects smoked cigarettes typical of those sold in the study market. The second study (NCT02474849; Los Angeles, USA) examined blood nicotine in 18 vapers who were occasional smokers using the same modular e-cigarettes ad libitum and compared these levels to when subjects smoked a single, market-typical combustible cigarette. Both studies were approved by local, independent research ethics committees and were run in accordance with Good Clinical Practice. Subjects provided written informed consent prior to study participation and were deemed healthy following medical examination and clinical laboratory screening. Smoking status was verified by exhaled CO measurements. Before each study visit subjects abstained overnight from any tobacco or nicotine product use, also verified by exhaled CO. A 5 minute exposure period was used in both studies.

Part II of this presentation will describe data from these studies and what those data mean for our knowledge of nicotine delivery from e-cigarettes as well informing our future study designs.