Part two: an unblinded, parallel, randomized study to assess nicotine pharmacokinetics of four Vuse Solo ENDS flavors in smokers.

Introduction:
This text reports the findings of a clinical study on the nicotine pharmacokinetics (PK) parameters of Vuse Solo electronic nicotine delivery system (ENDS) flavor variants after a single ad libitum use in solus and dual users of cigarette and ENDS. The study was part of a regulatory submission to the FDa Center for Tobacco Products (CTP) and was reviewed by the FDa, which granted a marketing order for the Original (tobacco) flavor Vuse Solo ENDS cartridges and the Vuse Solo power unit.

Key Points:

* The study was a randomized, open-label, parallel-cohort study to assess nicotine uptake in human subjects following ENDS use.
* Subjects were given a 1-week at-home trial period to become familiar with the assigned Vuse IPs and were encouraged to use ENDS at least once a day while they continue to use their usual brand of cigarettes.
* Product use compliance during the at-home trial period was monitored by obtaining cartridge weight before the dispensing and after subject checked in to the site for overnight confinement.
* Subjects were randomized to specific ENDS flavors and were provided two cartridges with instructions for use. Product use compliance was checked by weighing ENDS cartridges three times before and after use to a sensitivity of 1 × 10–4 g before and after the at-home trial period.
* On Study Day 1, subjects arrived at the study site and began their check-in procedures prior to confinement. Subjects returned ENDS IP e-liquid cartridges from the at-home trial period to the site.
* On the morning of Study Day 2, each subject was given their assigned ENDS IP for use during the PK assessment. Subjects were then allowed to use the assigned ENDS IP ad libitum for 10 min (± 10 s).
* Blood samples were collected and processed to plasma for nicotine measurements at the following time points relative to the start of IP use: − 5, − 0.5, 3, 5, 8, 10, 11, 12, 15, 20, 30, and 60 min.
* The primary PK parameters (Cmax, aUC nic0–60) were summarized using descriptive statistics by IP group without inter-group comparisons.

Main Message:
The study found that the primary endpoints of Cmax and aUC nic0-60 were similar across all four flavors as evidenced by the overlap of 95% confidence intervals. however, the study suggests that flavors are not the primary drivers in nicotine exposure in an acute exposure setting as much as individual use behavior. Therefore, future study designs could address the flavor comparisons to add to the growing body of literature regarding the effects of flavors on nicotine delivery and uptake.

Keyser BM, hong KS, DeLuca P, et al. Part two: an unblinded, parallel, randomized study to assess nicotine pharmacokinetics of four Vuse Solo ENDS flavors in smokers. Scientific reports. 2023;13(1):8894. doi:10.1038/s41598-023-35439-3