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

Abstract

Electronic nicotine delivery systems (ENDS) offer adult combustible cigarette smokers an alternative, potentially reduced harm, mode of nicotine delivery, attributed to fewer and reduced levels of harmful and potentially harmful constituents (HPHCs) in their aerosols compared to cigarette smoke. These two identical, randomised, open label, two-part studies aimed to compare levels of 15 biomarkers of exposure (BoE) to selected HPHCs associated with tobacco smoking in healthy US adult smoker subjects (n = 72). Following 9 days of exclusive use of a range of allocated myblu^™ ENDS variants, subjects' levels of 14 non-nicotine BoE were substantially reduced compared to baseline values (combustible cigarette use), in the range of 46-97%. BoE reductions were sustained in subjects who continued myblu use exclusively (n = 25) for a further 5 days, and returned to near baseline levels in subjects who returned to exclusive combustible cigarette use (n = 21). Dual users (n = 24) demonstrated reductions in BoE to a lesser extent than with exclusive myblu use. Measured nicotine equivalents did not significantly change throughout the study. These data suggest exclusive use of ENDS provides adult smokers seeking an alternative to combustible cigarettes with substantial reductions in HPHC exposures whilst achieving satisfying levels of nicotine delivery. Dual use involving substitution of cigarettes may also provide some of this advantage, but to lesser extent. Overall, the data contribute to the weight of evidence that ENDS are an important tool in tobacco harm reduction for adult smokers unwilling to or uninterested in quitting smoking. Study 1: NCT04430634, study 2: NCT04429932, clinicaltrials.gov (10-06-2020).

Keywords: Biomarkers of exposure; Cigarette; Electronic nicotine delivery systems; Smoking; Tobacco harm reduction; e-Cigarettes.

Fig. 1

Overview of the study design. Following screening, participants checked-in to their respective clinical research unit on Day 2. On Days 2 through 1 (24 h) baseline BoE assessments were made followed by randomisation to the myblu ENDS product use sequences detailed, Days 1 through 9 (Part 1). Details of the products (A–H) for identical Studies 1 and 2 can be found in Table 1 (n = number of participants intended to participate in one Study). In Part 2 of the Studies, participants were randomised to one of three study arms (I, J or K, detailed in Table 2). Participant follow-up was carried out approximately 14 days after the end of the study to determine if any adverse events had occurred

Fig. 2

Relative levels of 14 biomarkers of exposure (BoE) following selected product use, measured at Days 9 and 14 of Study 1. Values are expressed relative (%) to baseline levels (combustible cigarette smoking) measured on Day 1 and are detailed in labels on the bars. Red bars represent participants who switched from exclusive myblu use to exclusively smoking their usual brand of cigarette on Day 10 of the Study (arm 1 J) (n = 11); green bars represent dual-use (50% reported usual brand cigarette smoking and myblu use ad libitum from Day 10 of the Study) participants (arm 1 K) (n = 12); blue bars represent participants who continued to exclusively using their selected myblu products ad libitum from Day 10 of the Study (arm 1I) (n = 14). Definitions of abbreviated BoE can be found in Table 3 (color figure online)

Fig. 3

Relative levels of 14 biomarkers of exposure following selected product use, measured at Days 9 and 14 of Study 2. Values are expressed relative (%) to baseline levels (combustible cigarette smoking) measured on Day 1 and are detailed in labels on the bars. Red bars represent participants who switched from exclusive myblu use to exclusively smoking their usual brand of cigarette on Day 10 of the Study (arm 2 J) (n = 10); green bars represent dual-use (50% reported usual brand cigarette smoking and myblu use ad libitum from Day 10 of the Study) participants (arm 2 K) (n = 12); blue bars represent participants who continued to exclusively using their selected myblu products ad libitum from Day 10 of the Study (arm 2I) (n = 11). Definitions of abbreviated BoE can be found in Table 3 (color figure online)