Trial Outcomes & Findings for Free-Base Nicotine or Nicotine Salt e-Liquids in Current E-Cigarette Smokers, PeloPET Study (NCT NCT05455086)
NCT ID: NCT05455086
Last Updated: 2025-03-24
Results Overview
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.
COMPLETED
NA
21 participants
1.5 hours
2025-03-24
Participant Flow
1 participant was consented and enrolled in the study but found to be ineligible during visit 1, prior to randomization.
Participant milestones
| Measure |
Arm I (Protonated E-liquid, Unprotonated E-liquid)
Visit 2: Patients sample protonated e-liquid
Visit 3: Patients sample unprotonated e-liquid
|
Arm II (Unprotonated E-liquid, Protonated E-liquid)
Visit 2: Patients sample unprotonated e-liquid
Visit 3: Patients sample protonated e-liquid
|
|---|---|---|
|
Overall Study
STARTED
|
12
|
8
|
|
Overall Study
Sample Protonated E-liquid
|
12
|
8
|
|
Overall Study
Sample Unprotonated E-liquid
|
12
|
8
|
|
Overall Study
COMPLETED
|
12
|
8
|
|
Overall Study
NOT COMPLETED
|
0
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Free-Base Nicotine or Nicotine Salt e-Liquids in Current E-Cigarette Smokers, PeloPET Study
Baseline characteristics by cohort
| Measure |
Arm I (Protonated E-liquid, Unprotonated E-liquid)
n=12 Participants
Visit 2: Patients sample protonated e-liquid Visit 3: Patients sample unprotonated e-liquid
|
Arm II (Unprotonated E-liquid, Protonated E-liquid)
n=8 Participants
Visit 2: Patients sample unprotonated e-liquid Visit 3: Patients sample protonated e-liquid
|
Total
n=20 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
34.17 years
STANDARD_DEVIATION 7.91 • n=5 Participants
|
31.50 years
STANDARD_DEVIATION 7.27 • n=7 Participants
|
33.10 years
STANDARD_DEVIATION 7.58 • n=5 Participants
|
|
Sex: Female, Male
Female
|
7 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
11 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
5 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
9 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Asian
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Black or African American
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
White
|
12 Participants
n=5 Participants
|
6 Participants
n=7 Participants
|
18 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Middle Eastern
|
0 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
More than one race
|
0 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
|
Years of regular e-cigarette use
|
3.67 years
STANDARD_DEVIATION 2.84 • n=5 Participants
|
4.13 years
STANDARD_DEVIATION 2.95 • n=7 Participants
|
3.85 years
STANDARD_DEVIATION 2.81 • n=5 Participants
|
PRIMARY outcome
Timeframe: 1.5 hoursPopulation: Scan data from 3 participants was insufficient for calculating TAD and are not included in the statistics presented here, these participants were used for protocol optimizations.
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.
Outcome measures
| Measure |
Protonated E-liquid
n=34 PET Scans
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=34 PET Scans
Patients sample unprotonated e-liquid
|
|---|---|---|
|
PET/CT Imaging of the Head
|
2.81 %TAD/kg
Standard Deviation 0.92
|
2.40 %TAD/kg
Standard Deviation 0.62
|
PRIMARY outcome
Timeframe: 1.5 hoursPopulation: Scan data from 3 participants was insufficient for calculating TAD and are not included in the statistics presented here, these participants were used for protocol optimizations.
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.
Outcome measures
| Measure |
Protonated E-liquid
n=34 PET Scans
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=34 PET Scans
Patients sample unprotonated e-liquid
|
|---|---|---|
|
PET/CT Imaging of the Chest
Upper Respiratory Tract
|
6.18 %TAD/kg
Standard Deviation 2.17
|
11.62 %TAD/kg
Standard Deviation 3.17
|
|
PET/CT Imaging of the Chest
Lower Respiratory Tract
|
10.35 %TAD/kg
Standard Deviation 3.49
|
5.53 %TAD/kg
Standard Deviation 0.81
|
PRIMARY outcome
Timeframe: approx. 30 minutesPopulation: Puffing topography was not able to be recorded for 2 participants while sampling the Protonated e-liquid and 1 participant while sampling the Unprotonated e-liquid.
Puffing topography data was captured by the study e-cigarette to determine the puff volume.
Outcome measures
| Measure |
Protonated E-liquid
n=35 Puffs
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=36 Puffs
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Puff Volume (mL)
|
79.35 mL
Standard Deviation 72.75
|
73.76 mL
Standard Deviation 70.82
|
PRIMARY outcome
Timeframe: approx. 30 minutesPopulation: Puffing topography was not able to be recorded for 2 participants while sampling the Protonated e-liquid and 1 participant while sampling the Unprotonated e-liquid.
Puffing topography data was captured by the study e-cigarette to determine the puff duration.
Outcome measures
| Measure |
Protonated E-liquid
n=35 Puffs
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=36 Puffs
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Puff Duration (s)
|
2.87 seconds
Standard Deviation 1.43
|
2.82 seconds
Standard Deviation 1.61
|
PRIMARY outcome
Timeframe: approx. 5 minutesAge of first use will be assessed using the tobacco use history questionnaire.
Outcome measures
| Measure |
Protonated E-liquid
n=12 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=8 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Age of First Tobacco Use
|
14.58 years
Standard Deviation 2.02
|
14.63 years
Standard Deviation 1.60
|
PRIMARY outcome
Timeframe: approx. 5 minutesYears of tobacco use will be assessed using the tobacco use history questionnaire.
Outcome measures
| Measure |
Protonated E-liquid
n=12 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=8 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Years of Tobacco Use
|
19.58 years
Standard Deviation 8.85
|
16.88 years
Standard Deviation 6.75
|
PRIMARY outcome
Timeframe: approx. 5 minutesYears of regular use of nicotine/tobacco products will be assessed using the tobacco history questionnaire
Outcome measures
| Measure |
Protonated E-liquid
n=12 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=8 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Years of Regular Use of Nicotine/Tobacco Products
|
16.83 years
Standard Deviation 8.99
|
15.13 years
Standard Deviation 6.90
|
PRIMARY outcome
Timeframe: approx. 5 minutesPopulation: 2 participants in Arm I declined to provide a response for the number of days they have used cigarettes in the past 30 days.
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.
Outcome measures
| Measure |
Protonated E-liquid
n=12 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=8 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Past 30 Day Use of Nicotine/Tobacco Products
Cigarettes
|
0 days
Standard Deviation 0
|
0.75 days
Standard Deviation 2.12
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Pipes
|
0 days
Standard Deviation 0
|
0 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Cigars
|
0 days
Standard Deviation 0
|
0 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Cigarillos
|
0 days
Standard Deviation 0
|
0 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Little Cigars
|
0 days
Standard Deviation 0
|
0 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
e-cigarettes
|
29.83 days
Standard Deviation 0.58
|
30.00 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Smokeless Tobacco
|
0 days
Standard Deviation 0
|
0 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Snus
|
0 days
Standard Deviation 0
|
0 days
Standard Deviation 0
|
|
Past 30 Day Use of Nicotine/Tobacco Products
Hookah
|
0.17 days
Standard Deviation 0.58
|
0 days
Standard Deviation 0
|
PRIMARY outcome
Timeframe: approx. 5 minutesPopulation: mCEQ was only evaluated during the second study visit
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.
Outcome measures
| Measure |
Protonated E-liquid
n=12 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=8 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Modified Cigarette Evaluation Questionnaire (mCEQ)
Satisfaction
|
2.28 Score on a scale
Standard Deviation 1.31
|
1.42 Score on a scale
Standard Deviation 0.92
|
|
Modified Cigarette Evaluation Questionnaire (mCEQ)
Psychological Reward
|
2.17 Score on a scale
Standard Deviation 1.27
|
1.38 Score on a scale
Standard Deviation 0.93
|
|
Modified Cigarette Evaluation Questionnaire (mCEQ)
Aversion
|
0.88 Score on a scale
Standard Deviation 1.05
|
0.94 Score on a scale
Standard Deviation 1.47
|
|
Modified Cigarette Evaluation Questionnaire (mCEQ)
Enjoyment of Respiratory Tract Sensations
|
2.42 Score on a scale
Standard Deviation 1.31
|
1.25 Score on a scale
Standard Deviation 1.16
|
|
Modified Cigarette Evaluation Questionnaire (mCEQ)
Craving Reduction
|
3.67 Score on a scale
Standard Deviation 2.10
|
3.25 Score on a scale
Standard Deviation 1.83
|
PRIMARY outcome
Timeframe: approx. 5 minutesPopulation: The drug effects liking questionnaire was only administered during the second study visit
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.
Outcome measures
| Measure |
Protonated E-liquid
n=12 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=8 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Drug Effects Liking Questionnaire (DEQ)
Want
|
60.08 units on a scale
Standard Deviation 29.44
|
42.88 units on a scale
Standard Deviation 26.69
|
|
Drug Effects Liking Questionnaire (DEQ)
Like
|
51.25 units on a scale
Standard Deviation 32.76
|
32.50 units on a scale
Standard Deviation 25.93
|
|
Drug Effects Liking Questionnaire (DEQ)
Enjoy
|
57.25 units on a scale
Standard Deviation 30.63
|
31.88 units on a scale
Standard Deviation 26.38
|
|
Drug Effects Liking Questionnaire (DEQ)
Pleasurable
|
56.08 units on a scale
Standard Deviation 32.42
|
29.13 units on a scale
Standard Deviation 26.94
|
|
Drug Effects Liking Questionnaire (DEQ)
Satisfying
|
60.33 units on a scale
Standard Deviation 32.66
|
35.63 units on a scale
Standard Deviation 28.54
|
PRIMARY outcome
Timeframe: aprox. 5 minutesUrges/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.
Outcome measures
| Measure |
Protonated E-liquid
n=20 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=20 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Modified Tiffany-Drobes Questionnaire of Smoking Urges: Brief Form (QSU)
Desire
|
29.45 Score on a scale
Standard Deviation 6.83
|
30.15 Score on a scale
Standard Deviation 5.82
|
|
Modified Tiffany-Drobes Questionnaire of Smoking Urges: Brief Form (QSU)
Relief
|
16.35 Score on a scale
Standard Deviation 8.01
|
17.40 Score on a scale
Standard Deviation 9.38
|
PRIMARY outcome
Timeframe: approx. 5 minutesNicotine 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.
Outcome measures
| Measure |
Protonated E-liquid
n=20 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=20 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Minnesota Nicotine Withdrawal Scale
MNWS
|
9.50 score on a scale
Standard Deviation 7.38
|
9.10 score on a scale
Standard Deviation 6.32
|
|
Minnesota Nicotine Withdrawal Scale
MNWS Craving
|
2.60 score on a scale
Standard Deviation 0.94
|
2.70 score on a scale
Standard Deviation 1.17
|
PRIMARY outcome
Timeframe: approx. 5 minutesExhaled breath carbon monoxide was collected before each scan with a handheld electrochemical device.
Outcome measures
| Measure |
Protonated E-liquid
n=20 Participants
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=20 Participants
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Exhaled Breath Carbon Monoxide (CO)
|
2.45 ppm
Standard Deviation 1.79
|
2.80 ppm
Standard Deviation 2.31
|
Adverse Events
Protonated E-liquid
Unprotonated E-liquid
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Protonated E-liquid
n=20 participants at risk
Patients sample protonated e-liquid
|
Unprotonated E-liquid
n=20 participants at risk
Patients sample unprotonated e-liquid
|
|---|---|---|
|
Respiratory, thoracic and mediastinal disorders
Cough
|
10.0%
2/20 • Number of events 2 • Over 3 study visits, up to 3 months
|
0.00%
0/20 • Over 3 study visits, up to 3 months
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place