A study to assess if nicotine delivered via an e-cigarette can have an effect on appetite in healthy adult smokers

INTERVENTION: The order of the Investigational Product use will be randomised (using a Williams Latin square design) for this 5‐period crossover study. The Investigational Products in this study are as follows: 1. No Treatment (Control 1) 2. Combustible Cigarette (Control 2) 3. EPEN3.0_VGT00 (Placebo 1) 4. EPEN3.0_VGT12 (Intervention 1) 5. EPEN3.0_VGT18 (Intervention 2) Each participant will use the e‐Cigarette or cigarette for a 5 min session of ad‐libitum puffing regimen (puffing as participants feel necessary for 5 min). Participant will use one Investigational Product per study session. There will be 5 study sessions for each participant. Participants will abstain from nicotine, caffeine, and alcohol 12 h prior to the start of each study session. There will be at least 7 days between the administrations of each study session. CONDITION: Cigarette smoking ; Not Applicable ; Tobacco and nicotine use PRIMARY OUTCOME: 1. Calorie consumption (calorie counting) measured via Ad libitum meal at 70 min during each study session SECONDARY OUTCOME: ; 1. Leptin measure via a blood sample taken at 15 min prior to, and 0, 15, 30, 45, and 60 min after product usage; 2. Ghrelin measure via a blood sample taken at 15 min prior to, and 0, 15, 30, 45, and 60 min after product usage; 3. Insulin measure via a blood sample taken at 15 min prior to, and 0, 15, 30, 45, and 60 min after product usage; 4. Glucose measure via a blood sample taken at 15 min prior to, and 0, 15, 30, 45, and 60 min after product usage; 5. Peptide YY (PYY) measure via a blood sample taken at 15 min prior to, and 0, 15, 30, 45, and 60 min after product usage; 6. Glucagon‐like Peptide‐1 (GLP‐1) measure via a blood sample taken at 15 min prior to, and 0, 15, 30, 45, and 60 min after product usage; 7. Motivation to eat, as measured using the Subjective Appetite Questionnaire (VAS) at 15 min prior to, and 0, 15, 30, 45, 60, and 100 min after product usage; INCLUSION CRITERIA: 1. Healthy male or female subject, between 25 and 45 years of age, inclusive; 2. Female subject of childbearing potential willing to use a highly effective method of contraception or 2 effective methods of contraception, if applicable (unless of non‐childbearing potential or where abstaining from sexual intercourse is in line with the preferred and usual lifestyle of the subject) from the screening until the end of the follow‐up period; 3. Female subject of non‐childbearing potential. For the purposes of this study, this is defined as the subject being amenorrhoeic for at least 12 consecutive months or at least 4 months post‐surgical sterilisation (including bilateral fallopian tube ligation or bilateral oophorectomy with or without hysterectomy; documentation of the procedure is required); 4. Female subject with a negative pregnancy test at Screening who is not breastfeeding or lactating;<