Nicotine DependenceSREC22NCT05658471
Pharmacokinetics and Pharmacodynamics of Nicotine With Use of Standardized Research Electronic Cigarette (SREC)
A study testing Standardized Research E-Cigarette (SREC), Over the Counter E-Cigarette (EC) and Biological Samples in people with Nicotine Dependence and Tobacco Toxicity, run by University of California, San Francisco at 1 site in United States.
Trial summary
This is a crossover study that will examine use behaviors, chemical exposures, and biological effects of Standardized Research Electronic Cigarette (SREC) compared to usual brand e-cigarette use in natural or synthetic nicotine users. Read more about this study
- Who is it for?
- Ages 21 to 70 yearsHealthy volunteers can take part
- Conditions the study is for
- Nicotine Dependence, Tobacco Toxicity, Cardiovascular Risk Factors
- What is being tested?
- Standardized Research E-Cigarette (SREC), Over the Counter E-Cigarette (EC) and Biological Samples
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 32 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Feb 2023to 31 Jan 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 70 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy on the basis of medical history and limited physical examination-
- Heart rate < 105 beats per minute (BPM)*.
- Systolic Blood Pressure < 160 and > 90*.
- Diastolic Blood Pressure < 100 and > 50*.
- *considered out of range if both machine and manual readings are above/below these thresholds.
- Body Mass Index <= 38.0.
Show all 12Show fewer
- Current regular user of electronic cigarettes (EC)
- EC device use at least 15 or more days in the past 30 days (with e- liquid >= 3mg/ml)
- No restriction on flavor or type of e-cigarette used
- Saliva cotinine >= 50 ng/ml and/or NicAlert = 6
- Age >= 21 years old <= 70 years old
- Willingness to abstain from drug use for the duration of the study
Who cannot join
- The following unstable medical conditions:
- Heart disease
- Seizures
- Cancer
- Thyroid disease (okay if controlled with medication)
- Diabetes
Show all 31Show fewer
- Hepatitis B or C or Liver disease
- Glaucoma
- Kidney disease or urinary retention
- History of stroke
- An ulcer in the past year
- Active use of an inhaler for Asthma or chronic obstructive pulmonary disease (COPD)
- Medications
- Use of medications that are inducers of nicotine metabolizing enzyme CYP2A6 (Example: rifampicin, carbamazepine, phenobarbital, and other anticonvulsant drugs).
- Use of sympatholytic medications for cardiovascular conditions including hypertension (Example: beta and alpha-blockers).
- Concurrent use of nicotine-containing medications (Example: nicotine patch, lozenge, gum).
- Any stimulant medications (example: Adderall) generally given for attention deficit hyperactivity disorder (ADHD) treatment.
- Other/Misc. Health Conditions
- Oral thrush
- Fainting (within the last 30 days)
- Other "life threatening illnesses" as per principal investigator and/or study physician's discretion
- Pregnancy
- Pregnancy (self-reported and urine pregnancy test)
- Breastfeeding (determined by self-report)
- Women of childbearing potential must be using an acceptable method of contraception
- Concurrent participation in another clinical trial.
- Inability to read and write in English
- Planning to quit smoking or vaping within the next 60 days
- A known propylene glycol/vegetable glycerin allergy
- Uncomfortable with getting blood drawn
- Recent onset or change (worsening) in cough, fever and/or abdominal symptoms (vomiting or pain) in the past two weeks
Trial locations and contacts
1 site in 1 country.
United States1 site
University of California, San Francisco - Tobacco Research Center
San Francisco, California, 94143
About this study
Official title: Comparative Pharmacokinetics and Pharmacodynamics of Nicotine With Use of NIDA Standardized Research Electronic Cigarette (SREC) vs Usual Brand E-cigarette
This is a crossover study that will examine use behaviors, chemical exposures, and biological effects of Standardized Research Electronic Cigarette (SREC) compared to usual brand e-cigarette use in natural or synthetic nicotine users.
Read the detailed description
OBJECTIVES:
- To characterize nicotine delivery, systemic exposure and effects from SREC in comparison with usual to usual nicotine brand use.
II. To assess aspects of harm of SREC use compared to usual nicotine brand use.
OUTLINE:
Eligible participants will be assigned to one of two treatment conditions for the initial assessment which will take place in a hospital setting. The participant will then be assigned to the second condition within 2 weeks after the initial assessment which will also take place in a hospital setting to repeat the same procedures.
- Being tested
- Standardized Research E-Cigarette (SREC), Over the Counter E-Cigarette (EC), Biological Samples, Smoking-related Questionnaires
- Keywords
- Nicotine Pharmacokinetics, Nicotine Pharmacodynamics, Electronic Cigarettes, E-Cigarettes
- Medical subject headings
- Tobacco Use Disorder, Vaping
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Standardized Research E-Cigarette (SREC)Other
Standardized Research E-Cigarette (SREC) will be obtained through NJOY, LLC and provided at the hospital stay.
Over the Counter E-Cigarette (EC)Other
Also called Usual Brand E-Cigarette (EC)
Usual brand e-cigarettes will be provided at the hospital stay.
Biological SamplesBehavioural
Also called Biological Specimens
Blood, urine, and expired carbon dioxide will be obtained during the course of the study.
Smoking-related QuestionnairesOther
Also called Behavioral Questionnaires
Nicotine and Smoking behavior and dependence questionnaires will be administered at screening, before and during hospital stays.
| Study group | Role | What they receive |
|---|---|---|
| Usual Brand E-Cigarette (EC) then SREC | Experimental | Participants will be admitted to hospital research ward within 32 hours of the orientation visit and begin a standardized session of product use using the usual brand of e-cigarette that participants utilize for nicotine use, and will provide expired carbon dioxide samples, pharmacokinetic (PK) blood samples, urine samples, and have cardiovascular and vital signs monitored. Participants will also be asked to complete nicotine-related questionnaires. Participants will then return within 2 weeks to repeat the procedures using the SREC. Receives: Other: Standardized Research E-Cigarette (SREC); Other: Over the Counter E-Cigarette (EC); Behavioral: Biological Samples; Other: Smoking-related Questionnaires |
| SREC then Usual Brand E-Cigarette (EC) | Experimental | Participants will be admitted to hospital research ward within 32 hours of the orientation visit and begin a standardized session of product use using the SREC, and will provide expired carbon dioxide samples, pharmacokinetic (PK) blood samples, urine samples, and have cardiovascular and vital signs monitored. Participants will also be asked to complete nicotine-related questionnaires. Participants will then return within 2 weeks to repeat the procedures using the usual brand of e-cigarette that participants utilize for nicotine use. Receives: Other: Standardized Research E-Cigarette (SREC); Other: Over the Counter E-Cigarette (EC); Behavioral: Biological Samples; Other: Smoking-related Questionnaires |
What is being measured
The primary outcome is the main question the study is designed to answer.
Mean Peak Nicotine Concentration
The investigators will compare peak nicotine concentrations between SREC vs. EC use
Measured: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session
Mean Time of Peak Nicotine Concentration
Compare peak nicotine concentration between SREC vs. EC use.
Measured: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session
Area Under the plasma nicotine concentration-time Curve (AUC) at 120 minutes
Compare peak nicotine concentration between SREC vs. EC
Measured: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session
Mean overall systemic nicotine exposure
Descriptive statistics will be used to examine systemic nicotine exposure from use of SREC and compare to EC
Measured: during the 3 hr of ad libitum use
Mean inter-puff interval
The patterns of SREC puffing and EC use will be examined looking at the average and variability (SD) of inter-puff interval during the 3 hr of ad libitum use.
Measured: during the 3 hr of ad libitum use
Change in Mean score on the Modified Cigarette Evaluation Questionnaire (mCEQ)
The mCEQ use three multi-item domains (subscales) and two single items: "Smoking Satisfaction", "Psychological Reward", "Aversion", "Enjoyment of Respiratory Tract Sensations" and "Craving Reduction". Scores for each subscale are calculated as the average of its individual item responses of The items are rated on a seven-point scale ranging from 1 (not at all) to 7 (extremely). Higher scores indicate greater intensity of each smoking effect with, for example, greater satisfaction or psychological reward after smoking. Scores will be compared between SREC and EC use.
Measured: Up to 1 month
Change in Mean score on the Minnesota Tobacco Withdrawal Scale-Revised (MTWS-R)
The MTWS-R features two separate measures for examining the severity of nicotine withdrawal symptoms in a participant: a self-report scale and an observer scale. The observer scale asks the scale-taker to rate the severity of four symptoms in someone the they know who is experiencing nicotine withdrawal: "angry/irritable/frustrated," "anxious/tense," "depressed," and "restless/impatient." The self-report version asks for rankings of the severity of those same four symptoms, plus eleven others that cannot be observed by outsiders (including such things as "desire or craving to smoke," "insomnia, sleep problems, awakening at night," or "dizziness). Both scales use a Likert-type scale for the severity ratings, ranging from 0 ("not at all") to 4 ("severe"). These scores are tallied to calculate an a total withdrawal discomfort score and will be compared between SREC and EC use
Measured: Up to 1 month
Change in Mean score on the Questionnaire on Smoking Urges (QSU-Brief)
The QSU-Brief consists of 10 statements about the respondent's feelings and thoughts about the participants desire to smoke cigarettes as the participant is completing the questionnaire (i.e., right now). Each response is scored a number ranging from 1 (strongly disagree) to 7 (strongly agree) and total scores are calculated by summing the item scores to compare craving between SREC and EC use
Measured: Up to 1 month
Secondary outcomes (6)
Mean acrolein levels within participants
Urine excretion of mercapturic acid metabolites of volatile organic compounds (VOCs), with a particular focus on acrolein will be measured and compared between SREC and EC use
Measured: Up to 1 month
Mean propylene oxide levels within participants
Urine excretion of mercapturic acid metabolites of VOCs, with a particular focus on propylene oxide will be measured and compared between SREC and EC use
Measured: Up to 1 month
Median benzene levels within participants
Urine excretion of mercapturic acid metabolites of VOCs, with a particular focus on benzene will be measured and compared between SREC and EC use
Measured: Up to 1 month
Mean heart rate within participants
The cardiovascular effects of e-cigarette use as measured by heart rate will be compared between SREC and EC use
Measured: Up to 1 month
Mean blood pressure (both systolic and diastolic) within participants
The cardiovascular effects of e-cigarette use as measured by blood pressure will be compared between SREC and EC use
Measured: Up to 1 month
Mean plasma epinephrine within participants
The cardiovascular effects of e-cigarette use as measured by plasma epinephrine will be compared between SREC and EC use
Measured: Up to 1 month
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 Dec 2022
- Study start1 Feb 2023
- Primary completion31 Jan 2026
- Study completion31 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Nicotine DependenceStudies of the same condition, open and under way.
- More trials run by University of California, San FranciscoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Participants will be randomized to the starting condition using a Latin square design
- Masking
- None (open label)
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of California, San Francisco
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute on Drug Abuse (NIDA)
- Responsible party
- Sponsor
- Investigators
- Neal Benowitz, MD, Principal investigator, University of California, San Francisco
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05658471
- Sponsor's protocol ID
- SREC22
- Other IDs
- 5U01DA045519-02
- Acronym
- SREC22
- Status last verified
- Mar 2026
- First submitted
- 9 Dec 2022
- Last updated
- 27 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparative Pharmacokinetics and Pharmacodynamics of Nicotine With Use of NIDA Standardized Research Electronic Cigarette (SREC) vs Usual Brand E-cigarette
- ClinicalTrials.gov ID
- NCT05658471
- Acronym / sponsor ID
- SREC22 / SREC22
- Keywords
- Nicotine Pharmacokinetics, Nicotine Pharmacodynamics, Electronic Cigarettes, E-Cigarettes
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- University of California, San FranciscoUniversity, hospital or other
- Collaborators
- National Institute on Drug Abuse (NIDA)
- Study start
- 1 Feb 2023 (actual)
- Primary completion
- 31 Jan 2026 (actual)
- Study completion
- 31 Jan 2026 (actual)
- First posted
- 20 Dec 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a crossover study that will examine use behaviors, chemical exposures, and biological effects of Standardized Research Electronic Cigarette (SREC) compared to usual brand e-cigarette use in natural or synthetic nicotine users.
Detailed description
OBJECTIVES:
- To characterize nicotine delivery, systemic exposure and effects from SREC in comparison with usual to usual nicotine brand use.
II. To assess aspects of harm of SREC use compared to usual nicotine brand use.
OUTLINE:
Eligible participants will be assigned to one of two treatment conditions for the initial assessment which will take place in a hospital setting. The participant will then be assigned to the second condition within 2 weeks after the initial assessment which will also take place in a hospital setting to repeat the same procedures.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Participants will be randomized to the starting condition using a Latin square design
| Arm | Type | Receives |
|---|---|---|
| Usual Brand E-Cigarette (EC) then SREC | Experimental | Other: Standardized Research E-Cigarette (SREC), Other: Over the Counter E-Cigarette (EC), Behavioral: Biological Samples, Other: Smoking-related QuestionnairesParticipants will be admitted to hospital research ward within 32 hours of the orientation visit and begin a standardized session of product use using the usual brand of e-cigarette that participants utilize for nicotine use, and will provide expired carbon dioxide samples, pharmacokinetic (PK) blood samples, urine samples, and have cardiovascular and vital signs monitored. Participants will also be asked to complete nicotine-related questionnaires. Participants will then return within 2 weeks to repeat the procedures using the SREC. |
| SREC then Usual Brand E-Cigarette (EC) | Experimental | Other: Standardized Research E-Cigarette (SREC), Other: Over the Counter E-Cigarette (EC), Behavioral: Biological Samples, Other: Smoking-related QuestionnairesParticipants will be admitted to hospital research ward within 32 hours of the orientation visit and begin a standardized session of product use using the SREC, and will provide expired carbon dioxide samples, pharmacokinetic (PK) blood samples, urine samples, and have cardiovascular and vital signs monitored. Participants will also be asked to complete nicotine-related questionnaires. Participants will then return within 2 weeks to repeat the procedures using the usual brand of e-cigarette that participants utilize for nicotine use. |
Who may qualify
- Ages
- 21 to 70 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (12 listed)
- Healthy on the basis of medical history and limited physical examination-
- Current regular user of electronic cigarettes (EC)
- Age >= 21 years old <= 70 years old
- Willingness to abstain from drug use for the duration of the study
Key exclusion criteria (31 listed)
- The following unstable medical conditions:
- Medications
- Other/Misc. Health Conditions
- Pregnancy
- Concurrent participation in another clinical trial.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Standardized Research E-Cigarette (SREC)Standardized Research E-Cigarette (SREC) will be obtained through NJOY, LLC and provided at the hospital stay. | Other | SREC then Usual Brand E-Cigarette (EC), Usual Brand E-Cigarette (EC) then SREC |
| Over the Counter E-Cigarette (EC)Also: Usual Brand E-Cigarette (EC)Usual brand e-cigarettes will be provided at the hospital stay. | Other | SREC then Usual Brand E-Cigarette (EC), Usual Brand E-Cigarette (EC) then SREC |
| Biological SamplesAlso: Biological SpecimensBlood, urine, and expired carbon dioxide will be obtained during the course of the study. | Behavioural | SREC then Usual Brand E-Cigarette (EC), Usual Brand E-Cigarette (EC) then SREC |
| Smoking-related QuestionnairesAlso: Behavioral QuestionnairesNicotine and Smoking behavior and dependence questionnaires will be administered at screening, before and during hospital stays. | Other | SREC then Usual Brand E-Cigarette (EC), Usual Brand E-Cigarette (EC) then SREC |
Primary outcome
Mean Peak Nicotine Concentration
Time frame: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session
The investigators will compare peak nicotine concentrations between SREC vs. EC use
Mean Time of Peak Nicotine Concentration
Time frame: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session
Compare peak nicotine concentration between SREC vs. EC use.
Area Under the plasma nicotine concentration-time Curve (AUC) at 120 minutes
Time frame: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session
Compare peak nicotine concentration between SREC vs. EC
Mean overall systemic nicotine exposure
Time frame: during the 3 hr of ad libitum use
Descriptive statistics will be used to examine systemic nicotine exposure from use of SREC and compare to EC
Mean inter-puff interval
Time frame: during the 3 hr of ad libitum use
The patterns of SREC puffing and EC use will be examined looking at the average and variability (SD) of inter-puff interval during the 3 hr of ad libitum use.
Change in Mean score on the Modified Cigarette Evaluation Questionnaire (mCEQ)
Time frame: Up to 1 month
The mCEQ use three multi-item domains (subscales) and two single items: "Smoking Satisfaction", "Psychological Reward", "Aversion", "Enjoyment of Respiratory Tract Sensations" and "Craving Reduction". Scores for each subscale are calculated as the average of its individual item responses of The items are rated on a seven-point scale ranging from 1 (not at all) to 7 (extremely). Higher scores indicate greater intensity of each smoking effect with, for example, greater satisfaction or psychological reward after smoking. Scores will be compared between SREC and EC use.
Change in Mean score on the Minnesota Tobacco Withdrawal Scale-Revised (MTWS-R)
Time frame: Up to 1 month
The MTWS-R features two separate measures for examining the severity of nicotine withdrawal symptoms in a participant: a self-report scale and an observer scale. The observer scale asks the scale-taker to rate the severity of four symptoms in someone the they know who is experiencing nicotine withdrawal: "angry/irritable/frustrated," "anxious/tense," "depressed," and "restless/impatient." The self-report version asks for rankings of the severity of those same four symptoms, plus eleven others that cannot be observed by outsiders (including such things as "desire or craving to smoke," "insomnia, sleep problems, awakening at night," or "dizziness). Both scales use a Likert-type scale for the severity ratings, ranging from 0 ("not at all") to 4 ("severe"). These scores are tallied to calculate an a total withdrawal discomfort score and will be compared between SREC and EC use
Change in Mean score on the Questionnaire on Smoking Urges (QSU-Brief)
Time frame: Up to 1 month
The QSU-Brief consists of 10 statements about the respondent's feelings and thoughts about the participants desire to smoke cigarettes as the participant is completing the questionnaire (i.e., right now). Each response is scored a number ranging from 1 (strongly disagree) to 7 (strongly agree) and total scores are calculated by summing the item scores to compare craving between SREC and EC use
6 secondary outcomes
Mean acrolein levels within participants
Time frame: Up to 1 month
Mean propylene oxide levels within participants
Time frame: Up to 1 month
Median benzene levels within participants
Time frame: Up to 1 month
Mean heart rate within participants
Time frame: Up to 1 month
Mean blood pressure (both systolic and diastolic) within participants
Time frame: Up to 1 month
Mean plasma epinephrine within participants
Time frame: Up to 1 month
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Mar 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Neal Benowitz, MD principal investigator
University of California, San Francisco
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Standardized Research E-Cigarette (SREC), Over the Counter E-Cigarette (EC) and Biological Samples in people with Nicotine Dependence and Tobacco Toxicity, run by University of California, San Francisco at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 12 inclusion and 31 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 27 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Mean Peak Nicotine Concentration (time frame: Collected 2, 5, 7, 10, 15, 30, 45, 60, 75, 90, and 120 minutes post end vaping session). The study lists 8 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Mar 2026.