Reductions in biomarkers of exposure to selected harmful and potentially harmful constituents following exclusive and partial switching from combustible cigarettes to mybluTM electronic nicotine delivery systems (ENDS).

Introduction:
This text provides an overview of a study investigating the effects of electronic nicotine delivery systems (ENDS) on biomarkers of exposure (BoE) to harmful and potentially harmful constituents (hPhCs) in tobacco smoke. The study aims to compare the levels of 15 BoE in adult smokers who switch to exclusive use of my blu™ ENDS, dual use of ENDS and cigarettes, or exclusive cigarette smoking. The study also seeks to assess any changes in BoE levels following a 9-day exclusive use period of my blu™ ENDS products and the effects of switching back to cigarette smoking or dual use between days 9 and 14.

Key Points:

* The study included 72 subjects who were healthy US adult smokers aged 21-65 years.
* Subjects were randomized to use one of eight product use sequences during Part 1 of the study.
* In Part 2 of the study, subjects were randomized to one of three study groups: exclusive use of my blu ENDS products, exclusive smoking of usual brand cigarettes, or dual use of cigarettes and my blu ENDS products.
* The study measured 15 BoE, including COhb, NNaL, 3-hPMa, S-PMa, CEMa, hEMa, 3-hMPMa, MhBMa, o-tol, 1-aN, 2-aN, NNN, 1-OhP, 3-Oh B[a]P, and nicotine equivalents.
* The study found that all BoE, except for nicotine equivalents, demonstrated statistically significant reductions from baseline levels at Days 9 and 14 in the exclusive my blu use arms.
* The study also found that switching to exclusive cigarette use reversed the reductions in BoE observed after exclusive my blu ENDS use.
* Dual use of cigarettes and my blu ENDS products, where cigarette smoking is reduced, resulted in significant reductions in the majority of smoking-related hPhC BoE compared to baseline cigarette use.

Main Message:
The study provides evidence that exclusive use of ENDS products can result in significant reductions in BoE to hPhCs in tobacco smoke. however, switching back to exclusive cigarette use or dual use of cigarettes and ENDS products can reverse these reductions. The study also highlights the importance of complete smoking cessation following a period of dual use. Overall, the study supports the potential of ENDS products as a harm reduction tool for adult smokers who are unwilling or unable to quit smoking.

Morris P, McDermott S, Chapman F, et al. Reductions in biomarkers of exposure to selected harmful and potentially harmful constituents following exclusive and partial switching from combustible cigarettes to mybluTM electronic nicotine delivery systems (ENDS). Internal and emergency medicine. 2022;17(2):397-410. doi:10.1007/s11739-021-02813-w