Nicotine Regulation for Dual Users of E-cigarettes and Cigarettes

NCT06614504 · Status: RECRUITING · Phase: PHASE2 · Type: INTERVENTIONAL · Enrollment: 308

Last updated 2025-06-27

No results posted yet for this study

Summary

Cigarette smoking remains the leading cause of preventable morbidity and mortality in the US. Use of multiple tobacco products is becoming increasingly prevalent, with dual use of e-cigarettes and cigarettes representing the most common combination. Though e-cigarettes are not without risk, completely switching from cigarettes to e-cigarettes likely reduces risk for tobacco-related harm. However, many established dual users maintain long-term smoking and the majority who use e-cigarettes non-daily are at an even greater risk for prolonged smoking than exclusive cigarette smokers. The Food and Drug Administration Center for Tobacco Products (FDA CTP) has announced plans to implement a nicotine-limiting product standard, capping the nicotine in cigarettes at a minimally or non-addictive level. Randomized controlled trials (RCTs) demonstrate that adults who exclusively smoke cigarettes respond to very low nicotine content (VLNC) cigarettes with reductions in smoking, demand, and dependence. However, nicotine reduction RCTs to date have excluded people who regularly use e-cigarettes and therefore it remains unclear how a nicotine-limiting standard for cigarettes would affect smoking among dual users. Given the potential substitutability of e-cigarettes for cigarettes, reducing the nicotine in cigarettes could promote a transition to exclusive e-cigarette use among dual users unable to completely quit nicotine, but only if sufficiently appealing e-cigarettes remain available. E-cigarettes containing 5% nicotine-salt solution are currently most popular in the US, but policy makers have proposed restricting e-cigarettes to ≤ 2% nicotine to curb youth e-cigarette use, and several states have already set limits to reduce nicotine in e-cigarettes. Prior laboratory studies indicate that higher vs lower nicotine e-cigarettes serve as better substitutes for cigarettes among adult dual users. As such, a restriction on e-cigarette nicotine concentration could undermine the potential for e-cigarettes to substitute for cigarettes and diminish the benefits of a nicotine-limiting standard for cigarettes among dual users. This study is a 12-week double-blind 2 cigarette level (Normal Nicotine vs Very Low Nicotine) x 2 e-cigarette level (High Nicotine vs Low Nicotine) between-subjects factorial trial to investigate how a nicotine-limiting standard for cigarettes affects adult dual users and whether these effects are impacted by constraints on e-cigarette nicotine concentration. Outcome measures include cigarettes per day, cigarette dependence, and toxicant exposure. The research is highly relevant to FDA CTP domains of Addiction and Behavior because it will test whether reducing the nicotine content of cigarettes reduces smoking and dependence, and whether these effects are moderated by the availability of high vs low nicotine e-cigarettes.

Conditions

  • Tobacco Use Disorder

Interventions

OTHER

Varying the nicotine content of cigarettes

Altering the nicotine content of the tobacco research cigarettes

OTHER

Varying the nicotine content of e-cigarettes

Altering the nicotine content of the research e-cigarettes

Sponsors & Collaborators

  • University of Vermont

    lead OTHER

Principal Investigators

  • Elias Klemperer, PhD · University of Vermont

Study Design

Allocation
RANDOMIZED
Purpose
OTHER
Masking
TRIPLE
Model
FACTORIAL

Eligibility

Min Age
21 Years
Sex
ALL
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2024-11-01
Primary Completion
2028-08-31
Completion
2028-09-30

Countries

  • United States

Study Locations

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Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT06614504 on ClinicalTrials.gov