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Completed

NCT Number: NCT05455086

Free-Base Nicotine or Nicotine Salt e-Liquids in Current E-Cigarette Smokers, PeloPET Study

This clinical trial studies the effect of free-base compared with nicotine salt based e-liquids on electronic cigarette (EC) puffing behavior, abuse liability, and deposition and absorption of nicotine in the respiratory tract and rate of uptake in the brain in current EC smokers. The results from this study may provide much needed scientific information to public health officials and regulators.

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Key information

Conditions

Cigarette Smoking-Related Carcinoma

Age range

21 year–50 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Ohio State University Comprehensive Cancer Center

Columbus, Ohio, 43210, United States

About this study

PRIMARY OBJECTIVES:

I. To examine the influence of nicotine form on puffing behavior and abuse liability.

II. To evaluate the influence of nicotine form and concentration on nicotine distribution in the brain and respiratory tract.

OUTLINE:

VISIT 1: Patients sample 4-liquids to determine whether they can vape the unflavored e-liquid without coughing

Patients are randomized to 1 of 2 arms.

ARM I:

VISIT 2: Patients receive 1 puff of tobacco flavored or unflavored protonated e-liquid and undergo 0-15 minutes (min) head and 5 min chest positron emission tomography (PET)/computed tomography (CT) and then 0-15 min chest and 5 min head PET/CT. About 2 hours post initial PET/CT, patients receive a second puff of tobacco flavored or unflavored protonated e-liquid and undergo 0-15 min chest and 5 min head PET/CT and then 0-15 min head and 5 min chest PET/CT.

VISIT 3: Patients receive 1 puff of tobacco flavored or unflavored unprotonated e-liquid and undergo 0-15 min head and 5 min chest PET/CT and then 0-15 min chest and 5 min head PET/CT. About 2 hours post initial PET/CT, patients receive a second puff of tobacco flavored or unflavored unprotonated e-liquid and undergo 0-15 min chest and 5 min head PET/CT and then 0-15 min head and 5 min chest

ARM II:

VISIT 2: Patients receive 1 puff of tobacco flavored or unflavored unprotonated e-liquid and undergo 0-15 min head and 5 min chest PET/CT and then 0-15 min chest and 5 min head PET/CT. About 2 hours post initial PET/CT, patients receive a second puff of tobacco flavored or unflavored unprotonated e-liquid and undergo 0-15 min chest and 5 min head PET/CT and then 0-15 min head and 5 min chest.

VISIT 3: Patients receive 1 puff of tobacco flavored or unflavored protonated e-liquid and undergo 0-15 min head and 5 min chest PET/CT and then 0-15 min chest and 5 min head PET/CT. About 2 hours post initial PET/CT, patients receive a second puff of tobacco flavored or unflavored protonated e-liquid and undergo 0-15 min chest and 5 min head PET/CT and then 0-15 min head and 5 min chest PET/CT.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • A current exclusive e-cigarette user (>= 1 vaping bout per day) for at least the past 6 months (confirmed by NicAlert saliva testing strip)
  • Between 21-50 years old
  • Willing to provide informed consent and abstain from all tobacco and nicotine use for at least 12 hours prior to visits 2 and 3
  • Willing to participate in 3 laboratory visits
  • Read and speak English
  • If utilizing study provided rideshare services, will need to live within 20 miles of Wake Forest University

Exclusion criteria

  • Self-reported diagnosis of lung disease including asthma, cystic fibrosis, or chronic obstructive pulmonary disease
  • Unstable or significant psychiatric conditions (past and stable conditions will be allowed)
  • History of cardiac event or distress within the past 3 months
  • Currently pregnant (as indicated by urine pregnancy test at the start of each laboratory visit), planning to become pregnant, or breastfeeding (women only)
  • Use of other tobacco products (e.g., cigarette, cigar, etc.) > 5 days in the past month
  • Currently engaging in a tobacco product cessation attempt

Treatment and study plan

Cigarette Smoking

Behavioral

Receive 1 puff of tobacco flavored protonated e-liquid

Computed Tomography

Procedure

Undergo PET/CT

Other names: CAT, CAT Scan, Computerized Axial Tomography, Computerized Tomography, CT, CT Scan, tomography

Positron Emission Tomography

Procedure

Undergo PET/CT

Other names: Medical Imaging, Positron Emission Tomography, PET, PET Scan, Positron Emission Tomography Scan, Positron-Emission Tomography, proton magnetic resonance spectroscopic imaging

Questionnaire Administration

Other

Ancillary studies

Primary outcomes

  1. PET/CT Imaging of the Head

    Time frame: 1.5 hours

    Evaluate effect of nicotine form (free-base vs nicotine salt base) on nicotine absorption and distribution in the brain with total absorbed dose (TAD) of [11C]nicotine.

  2. PET/CT Imaging of the Chest

    Time frame: 1.5 hours

    Evaluate effect of nicotine form (free-base vs nicotine salt base) on nicotine absorption and distribution in the respiratory tract with total absorbed dose (TAD) of [11C]nicotine.

  3. Puff Volume (mL)

    Time frame: approx. 30 minutes

    Puffing topography data was captured by the study e-cigarette to determine the puff volume.

  4. Puff Duration (s)

    Time frame: approx. 30 minutes

    Puffing topography data was captured by the study e-cigarette to determine the puff duration.

  5. Age of First Tobacco Use

    Time frame: approx. 5 minutes

    Age of first use will be assessed using the tobacco use history questionnaire.

  6. Years of Tobacco Use

    Time frame: approx. 5 minutes

    Years of tobacco use will be assessed using the tobacco use history questionnaire.

  7. Years of Regular Use of Nicotine/Tobacco Products

    Time frame: approx. 5 minutes

    Years of regular use of nicotine/tobacco products will be assessed using the tobacco history questionnaire

  8. Past 30 Day Use of Nicotine/Tobacco Products

    Time frame: approx. 5 minutes

    Days used in the past 30 days of nicotine/tobacco products including cigars, cigarillos, little cigars, pipe tobacco, chewing tobacco, snuff, snus, EC/vape/mod/APV/e-hookah, and hookah tobacco.

  9. Modified Cigarette Evaluation Questionnaire (mCEQ)

    Time frame: approx. 5 minutes

    12-item modified Cigarette Evaluation Questionnaire (mCEQ) completed following e-cigarette self-administration to assess subjective responses. The 12-item mCEQ includes five subscales: Smoking Satisfaction, Psychological Reward, Aversion, Enjoyment of Respiratory Tract Sensations, and Craving Reduction, with items rated from 0 (not at all) to 6 (extremely likely). Scores for each subscale are calculated as the mean of the individual item responses or the single item. Higher scores indicate greater intensity on that scale.

  10. Drug Effects Liking Questionnaire (DEQ)

    Time frame: approx. 5 minutes

    An adapted version of the Drug Effects/Liking Questionnaire will assess the desire and liking of the study products. Five visual analog scale items ranging from 0 (not at all) to 100 (extremely) assessed wanting to vape the product again, liking the product, enjoying the product, finding the product pleasurable and satisfying. Higher scores indicate greater liking.

  11. Modified Tiffany-Drobes Questionnaire of Smoking Urges: Brief Form (QSU)

    Time frame: aprox. 5 minutes

    Urges/craving will be measured using a modified version of the Tiffany-Drobes Questionnaire of Smoking Urges: Brief Form. This is a 10-item measure where participants rate e-cigarette smoking-related items (All I want right now is an e-cigarette) on a 7-point Likert scale ranging from 1 (strongly disagree) to 7 (strongly agree). Similar to previous studies, we will collapse the items into two previously identified factors (Factor 1: strong desire and intention to smoke an e-cigarette; Factor 2: anticipation of relief from withdrawal symptoms). Scores are calculated by summing the items and range from 5 to 35 with higher scores indicating greater craving to vape.

  12. Minnesota Nicotine Withdrawal Scale

    Time frame: approx. 5 minutes

    Nicotine withdrawal will be assessed using the empirically validated 15-item version of the Minnesota Nicotine Withdrawal Scale (MNWS). Items were rated on a 5-point scale from 0 (none) to 4 (severe). This measure assesses smoking craving, anger/irritability, anxiety, depressed mood, restlessness/difficulty concentrating, increased appetite, sleep problems, and somatic symptoms (nausea, constipation, sore throat, dizziness, coughing). MNWS is the sum of 8 items with scores ranging from 0 to 32 and MNWS Craving is a single item with scores ranging from 0 to 4, higher scores indicate a greater craving.

  13. Exhaled Breath Carbon Monoxide (CO)

    Time frame: approx. 5 minutes

    Exhaled breath carbon monoxide was collected before each scan with a handheld electrochemical device.

Sponsors and collaborators

Lead sponsor

Ohio State University Comprehensive Cancer Center

Other

Registry information

Official study title

Free-Base Nicotine or Nicotine Salt e-Liquids in Current E-Cigarette Smokers, PeloPET

Important dates

Study start
2022
Primary completion
2023
Study completion
2023
First posted
Jul 13, 2022
Registry last updated
Mar 24, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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