CClinicalTrials.gg
CompletedNCT04090879Updated Apr 1, 2025Results posted

Low Nicotine Content Cigarettes in Vulnerable Populations: Affective Disorders

A Phase 2 interventional study of Either normal nicotine content cigarettes (15.8mg/g) or reduced nicotine content cigarettes (0.4mg/g) and E-Cigarettes in Tobacco Use Disorder, sponsored by Brown University. Completed at 2 sites in United States. Open to participants aged 18 Years to 70 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-04-01.

Sponsored by Brown University · Phase 2, Interventional, and Basic science

Phase
Phase 2
Study type
Interventional
Enrollment
326
Allocation
Randomized
Ages
18 Years to 70 Years
Sex
All
01

Study summary

While the prevalence of smoking in the United States general population has declined over the past 50 years, there has been little to no decline among people with mental health conditions. Affective Disorders (ADs) are the most common mental health conditions in the US, and over 40% of people with ADs are current smokers. A national policy of reducing the nicotine content of cigarettes has the potential to reduce tobacco use, dependence, and related adverse health outcomes. Controlled trials in psychiatrically-stable smokers have shown that reducing the nicotine content in cigarettes can reduce cigarettes per day (CPD), dependence and tobacco toxicant exposure, with few adverse consequences.

The goal of the proposed trial is to experimentally model whether increasing the availability and appeal of an alternative, non-combusted source of nicotine (e-cigarettes) moderates the effect of altering the nicotine in cigarettes in smokers with ADs. Additionally, investigators will test whether allowing participants to personalize the flavor of the e-liquid alters any moderating effects their availability may have on tobacco cigarette smoking.

Daily smokers with current ADs will be recruited at Brown University and the University of Vermont.

Investigators will study two research cigarettes referred to here as Research Cigarette 1 (RC1) and Research Cigarette 2 (RC2). One of these cigarettes will be a normal nicotine content cigarette and the other will be a reduced nicotine content cigarette. Investigators will study two e-cigarette conditions referred to here as E-Cigarette Condition 1 (EC1) and E-Cigarette Condition 2 (EC2). Both e-cigarette conditions will involve the same commercially available devices and same nicotine-containing e-liquid, but in one condition that e-liquid will be available only in tobacco flavor while in the other condition that e-liquid will be available in multiple flavors from which participants can choose based on personal taste preference. Participants will be assigned to one of the following four study conditions: (1) RC1 only; (2) RC2 only; (3) RC2 + EC1; (4) RC2 + EC2.

Participants will be asked to use only their assigned study products for 16 weeks. Outcome measures include total CPD, cigarette demand assessed by behavioral economics-based purchase tasks, craving, withdrawal, psychiatric symptoms, breath carbon monoxide (CO), biomarkers of tobacco toxicant exposure, brain function and structure, and airway inflammation (fractional nitric oxide concentration in exhaled breath [FeNO]).

02

Conditions studied

  • Tobacco Use Disorder

Keywords

  • Biomarkers of Exposure
  • Compensatory Smoking
  • Nicotine Dependence
  • Reduced Nicotine Cigarettes
  • Affective Disorders
  • Tobacco Withdrawal
  • Vulnerable Populations
  • E-Cigarettes
03

In context

Tobacco Use Disorder

968 studies on the registry are indexed under Tobacco Use Disorder; 126 are open to participants now.

This study's enrollment of 326 is above the median of 89 across 851 interventional studies indexed under Tobacco Use Disorder.

Browse Tobacco Use Disorder studies →

Lead sponsor

Brown University is the lead sponsor of 282 studies on the registry; 42 are open to participants now.

Of its 25 completed or terminated interventional studies of FDA-regulated products, 18 (72%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 70 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Between 21 years and 70 years old
  • Must have current diagnosis of an Affective Disorder.

Exclusion criteria

Exclusion Criteria

  • Being without an Affective Disorder
  • Younger than 21 years old
  • Older than 70 years old
05

Study design

Phase
Phase 2
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
326 participants (actual)

Study arms

  • Experimental
    RC 1 only

    Research Cigarettes #1

    Other: Either normal nicotine content cigarettes (15.8mg/g) or reduced nicotine content cigarettes (0.4mg/g)

  • Experimental
    RC 2 only

    Research Cigarettes #2

    Other: Either normal nicotine content cigarettes (15.8mg/g) or reduced nicotine content cigarettes (0.4mg/g)

  • Experimental
    RC 2 + EC 1

    Research Cigarettes #2 plus E-cigarettes #1 (participants receive tobacco flavor only)

    Other: Either normal nicotine content cigarettes (15.8mg/g) or reduced nicotine content cigarettes (0.4mg/g) · Other: E-Cigarettes

  • Experimental
    RC 2 + EC 2

    Research Cigarettes #2 plus E-cigarettes #2 (participants can choose among varying flavors)

    Other: Either normal nicotine content cigarettes (15.8mg/g) or reduced nicotine content cigarettes (0.4mg/g) · Other: E-Cigarettes

Interventions

  • OtherEither normal nicotine content cigarettes (15.8mg/g) or reduced nicotine content cigarettes (0.4mg/g)

    1) Altering the nicotine content of the tobacco research cigarette

  • OtherE-Cigarettes

    1) Altering the availability of e-cigarettes; 2) Altering option to personalize the e-liquid in the e-cig condition

06

What researchers measure

Primary outcomes

  1. Cigarettes Per Day

    Cigarettes per day will be assessed for use of cigarettes with different nicotine content.

    Time frame: 16 weeks

07

Results

Posted Apr 1, 2025

Participant flow

Participant flow — Overall Study
MilestoneRC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2
Started83857484
Completed67665770
Not completed16191714

Outcome measures

PrimaryCigarettes Per Day

Cigarettes per day will be assessed for use of cigarettes with different nicotine content.

Time frame:
16 weeks
Reported as:
Least squares mean · cigarettes per day
Cigarettes Per Day
cigarettes per dayRC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2
Cigarettes Per Day22.54 ± 1.5914.32 ± 1.3211.76 ± 1.187.63 ± 0.90

Adverse events

Collected over 16 weeks. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
RC 1 Only0/83 (0%)9/83 (10.8%)71/83 (85.5%)
RC 2 Only0/85 (0%)4/85 (4.7%)74/85 (87.1%)
RC 2 + EC 11/74 (1.4%)4/74 (5.4%)62/74 (83.8%)
RC 2 + EC 20/84 (0%)2/84 (2.4%)72/84 (85.7%)
Most frequent serious events
Showing 10 of 15
Most frequent serious events
EventRC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2
Psychiatric disorders - OtherPsychiatric disorders3/830/850/740/84
HypertensionVascular disorders1/830/851/740/84
Death NOSGeneral disorders0/830/851/740/84
Injury, poisoning, and procedural complicationsInjury, poisoning and procedural complications0/830/851/740/84
DehydrationMetabolism and nutrition disorders0/830/851/740/84
Esophageal perforationGastrointestinal disorders1/830/850/740/84
IrritabilityGeneral disorders1/830/850/740/84
Tumor PainNeoplasms benign, malignant and unspecified (incl cysts and polyps)1/830/850/740/84
Pregnancy, puerperium, and perinatal conditionsPregnancy, puerperium and perinatal conditions1/830/850/740/84
Surgical and medical procedures - OtherSurgical and medical procedures1/831/850/740/84
Most frequent other events
Showing 10 of 13
Most frequent other events
EventRC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2
OASIS Score IncreasePsychiatric disorders32/8331/8531/7431/84
BDI Category IncreasePsychiatric disorders29/8329/8526/7425/84
Psychiatric disordersPsychiatric disorders27/8328/8519/7424/84
Respiratory, thoracic and mediastinal disordersRespiratory, thoracic and mediastinal disorders23/8327/8518/7418/84
General disorders and administrationGeneral disorders18/8324/8516/7422/84
Infections and infestationsInfections and infestations16/8323/858/7410/84
Nervous system disordersNervous system disorders7/8318/8515/7410/84
Gastrointestinal disordersGastrointestinal disorders9/8317/8514/7417/84
Vascular disordersVascular disorders10/8313/858/7416/84
Musculoskeletal and connective tissue disordersMusculoskeletal and connective tissue disorders11/8316/857/7412/84

Baseline characteristics

Age, Continuous
Age, Continuous(years)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
Mean39.77 ± 10.9839.85 ± 9.2841.51 ± 12.3939.38 ± 10.5940.09 ± 10.79
Sex: Female, Male
Sex: Female, Male(Participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
Female65695059243
Male1816242583
Race/Ethnicity, Customized
Race/Ethnicity, Customized(Participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
Black, non-Latino969933
Latino433212
White, non-Latino66686068262
Non-Latino other or multiracial482519
Region of Enrollment
Region of Enrollment(participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
United States83857484326
Population
Population(Participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
Females with lower educational level2023162180
OUD1919171974
Affective disorders44434144172
Educational level
Educational level(Participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
<High school9431430
High school graduate, equivalency, or some college51574647201
Associate's degree811131143
≥College graduate1513121252
Marital status
Marital status(Participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
Married815171151
Never married49473648180
Divorced, separated, or widowed2623212595
Primarily smokes mentholated cigarettes
Primarily smokes mentholated cigarettes(Participants)RC 1 OnlyRC 2 OnlyRC 2 + EC 1RC 2 + EC 2Total
Count of participants32353133131

7 further baseline measures are reported on the registry.

08

Study locations

2 sites
  • Brown University
    Providence, Rhode Island 02912, United States
  • University of Vermont
    Burlington, Vermont 05401, United States
09

References and documents

Study documents

  • Protocol and statistical analysis plan · Jan 23, 2023
  • Informed consent form · Jan 23, 2023

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: Yes

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 1, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT04090879
Lead sponsor
Brown University
Collaborators
Food and Drug Administration (FDA), National Institute on Drug Abuse (NIDA), University of Vermont
Responsible party
Jennifer Tidey (Professor, Brown University) — Principal investigator
First posted
Sep 16, 2019
Start date
Oct 18, 2020
Primary completion
Nov 27, 2023
Completion
Nov 27, 2023
Results posted
Apr 1, 2025
Last update
Apr 1, 2025

Study contacts

Jennifer W Tidey, Ph.D.
principal investigator · Brown University

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Mar 2025. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion