# Project 4

> **NIH NIH U54** · UNIVERSITY OF SOUTHERN CALIFORNIA · 2022 · $422,433

## Abstract

ABSTRACT: PROJECT 4 (P4)
Background: E-cigarettes pose a regulatory challenge because they may adversely impact the health of some
populations (e.g., young never-smokers), but reduce health risk in others (e.g., middle-aged/older smokers who
switch to e-cigarettes). P4 aims to provide FDA with evidence to inform regulatory restrictions of dimensions of
e-cigarette product diversity that put young adult never-smokers at risk of using e-cigarettes, yet does not deter
middle/older adult smokers from adopting and potentially switching to e-cigarettes. P4 will test the hypotheses
regarding how product diversity impacts the user experience—a key channel of exposure: a) Young never-smok-
ers may prefer e-liquids with sweet flavorings due to age-related taste preferences and menthol flavors that mask
the bitterness of nicotine; yet, middle-age/adult smokers may be more accustomed to tobacco flavorings, b) E-
liquid labels with cartoon images and youth-oriented product names (e.g., ‘Killer Kustard’) may appeal more to
young (vs. middle-age/older) adults. c) Low propylene glycol (PG)/vegetable glycerin (VG) ratio in e-liquids pro-
duces thick ‘vapor clouds’ and a weak throat hit, which may appeal to young adults, but middle-age/older adult
smokers may prefer vapor that resembles cigarette smoke. Method: Drawing from the USC-TCORS cohort and
Population Core resources, P4 will compare never-smoking young adult e-cigarette users to middle-age/older
adult smokers with an interest in, but no significant experience with, e-cigarettes. In two studies, subjects will
self-administer e-cigarette products systematically varied according to Flavor (sweet vs. menthol vs. tobacco) ×
PG/VG ratio (20:80 vs. 40:60 vs. 60:40 vs. 80:20) × Packaging (e-liquid characterizing flavor label [e.g., “peach”]
vs. youth-oriented non-characterizing flavor [e.g., “gummy heaven”] vs. non-characterizing flavor + cartoon) de-
sign. The Aim 1 study will test product exposure effects on subjective ratings of appeal (e.g., liking, desire to use
again). The Aim 2 study will test product exposure effects on choice to use (vs. earn money): a) The previously-
exposed e-cigarette product (an abuse liability test; never-smoking young adults only), or b) Own brand ciga-
rettes (test of ability to resist smoking; middle-age/older adult smokers only). Aim 1. Determine which dimen-
sions of e-cigarette product diversity differentially affect appeal across never-smoking young adult e-cigarette
users (N=200) and middle-age/older smokers (N=200). Aim 2. Determine which dimensions of e-cigarette prod-
uct diversity differentially affect abuse liability in never-smoking young adult e-cigarette users (N=360) and ability
to resist smoking in middle-age/older adult smokers (N=360). Integration with “Intersections of Products with
Populations” theme: P4 will study dimensions of e-cigarette product diversity common to those studied in other
USC-TCORS projects using a unique controlled experimental paradigm to i...

## Key facts

- **NIH application ID:** 10488696
- **Project number:** 5U54CA180905-10
- **Recipient organization:** UNIVERSITY OF SOUTHERN CALIFORNIA
- **Principal Investigator:** Adam Matthew Leventhal
- **Activity code:** U54 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $422,433
- **Award type:** 5
- **Project period:** 2013-09-19 → 2023-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10488696

## Citation

> US National Institutes of Health, RePORTER application 10488696, Project 4 (5U54CA180905-10). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10488696. Licensed CC0.

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