NCT04003805.

Study name	Biomarkers of exposure and effect in standardized research e‐cigarette (SREC) users
Methods	Design: RCT Setting: USA
Participants	Estimated enrolment: 125 Inclusion criteria: 18‐65 smokers willing to stop smoking and completely switch to EC or medicinal nicotine  ≥ 5 cigarettes daily and not using any other nicotine or tobacco product; biochemically confirmed Smoking daily for at least 1 year and no serious quit attempts  Exclusion criteria: Regular tobacco or nicotine product use other than cigarettes Currently using NRT or other tobacco cessation products Significant immune system disorders, respiratory diseases, kidney or liver diseases or any other medical disorders that may affect biomarker data; taking anti‐inflammatory medications; unstable health conditions; unstable mental health; excessive drinking; positive toxicology screen for illicit any drugs: pregnant or breastfeeding For a full list see NCT record.
Interventions	EC: Standardized Research E‐cigarette (SREC)  Arm 1: Experimental: Switching from Smoking Cigarettes to E (SREC)  The device operates at a single output voltage (3.30 ± 0.05 V) and uses sealed disposable 3 mL cartridges with tobacco‐flavoured e‐liquid (~350 puffs/cartridge). The concentration of nicotine in e‐liquid is 15 mg/mL, and the vehicle composition is 50:50 propylene glycol and glycerin. The device uses a battery that can be recharged via a micro USB port.  Arm 2: Experimental: Switching from smoking cigarettes to nicotine mini‐lozenge We will use commercially available nicotine mini‐lozenges containing 2 or 4 mg nicotine/lozenge (Nicorette, manufactured by GlaxoSmithKline). Dose will be determined per instructions on the package (e.g. if smoking within 30 minutes upon awakening, then 4 mg dose will be prescribed).
Outcomes	1 year 4 & 8 weeks for formaldehyde‐DNA adducts & oxidative DNA adduct 8‐oxo‐dG in DNA Biomarkers: TNE, NNAL, NNN, PneT, mercapturic acids HMPMA, 2‐HPMA, 3‐HPMA, formaldehyde‐DNA adducts, oxidative DNA adduct 8‐oxo‐dG in DNA, NNN and nornicotine, HPB‐releasing DNA adducts cpd, product use (EC & nicotine lozenges), CC avoidance
Starting date	Actual start date: May 11 2022. Estimated study completion date: January 15 2023
Contact information	Hanna Vanderloo, RN, MSN 612.624.4983, hannav@umn.edu
Notes	New to 2022 update