Abstract
Rationale
Nicotine pharmacokinetics and subjective effects are important factors in assessing the abuse liability of tobacco products such as electronic nicotine delivery systems (ENDS). In addition, an abuse liability determination is informative in assessing the ability of ENDS to support switching from cigarette smoking.
Objectives
To assess nicotine pharmacokinetics, subjective effects, and short-term safety profiles of the RELX Infinity ENDS compared with other tobacco/nicotine products among current smokers and ENDS users.
Methods
Two similar but independent studies were conducted to assess the abuse liability of Infinity tobacco-and menthol-flavored ENDS compared with combustible cigarettes and nicotine replacement therapy gum in smokers and compared with usual brand ENDS in ENDS users.
Results
In smokers, nicotine delivery (in terms of Cmax and AUC) from both Infinity ENDS flavors was lower than that from combustible cigarettes but higher than that from nicotine gum. Use of Infinity ENDS robustly reduced urges to smoke and elicited subjective effects such as satisfaction which were intermediate to those of cigarettes and nicotine gum. In ENDS users, Infinity ENDS delivered nicotine comparably to subjects’ usual brand ENDS and elicited generally similar subjective effects.
Conclusions
The abuse liability of two flavors of the RELX Infinity ENDS is lower than that of combustible cigarettes, higher than that of nicotine gum, and similar to that of other ENDS products. This supports a potential positive role in tobacco harm reduction, by providing smokers with a satisfying alternative to combustible cigarettes which could support switching away from smoking to a degree better than the support provided by nicotine gum while presenting a lower initiation/addiction risk among nicotine non-users than currently marketed tobacco products.