Study design
ADVERSE EVENTS
The study was designed as a randomized, open-label, parallel-cohort study to assess nicotine uptake in human subjects following ENDS use. The study examined plasma nicotine PK parameters in Vuse Solo ENDS with four flavor variants: Original, Mint, Tropical and Fusion.Subjects were given a 1-week at-home trial period to become familiar with the assigned Vuse IPs. Subjects were encouraged to use ENDS at least once a day at-home trial period while they continue to use their usual brand of cigarettes. The 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 × 10On 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. Eligibility criteria were reconfirmed, and those who successfully completed all check-in procedures were confined to the study site for approximately 24 h. Subjects were allowed to use their assigned IP ad libitum until the start of a mandatory 12-h abstinence from tobacco and nicotine products.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). Start and stop times were documented. ENDS IP cartridges were weighed three times before and after use to 1 × 10During the PK assessment, 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 − 0.5 min sample was used as the preferred baseline sample. Samples were collected and centrifuged within 60 min of collection. The plasma was transferred into 2 methanol pre-washed tubes and frozen prior to shipment on dry ice to the bioanalytical lab. All samples were transferred to Celerion Global Bioanalytical Services (Lincoln, NE) for nicotine quantitation using a validated liquid chromatography tandem mass spectrometry method.
In addition to blood sample collection, subjects were required to provide an OPL score at 13 min after start of IP use on a numeric scale of 0 to 10, with 0 corresponding to “strongly dislike,” 5 corresponding to “neither like nor dislike”, and 10 corresponding to “strongly like.” Each subject was assessed for adverse events and vital signs, and a symptom-driven physical examination was performed, if necessary, prior to discharge from the study to ensure subject’s safety. Upon the PI’s review of subjects’ status, if there were no new adverse events or physical examination findings to warrant further follow up, subjects were discharged from the study.