Trial Outcomes & Findings for Biomarkers of Exposure and Effect in Standardized Research E-cigarette (SREC) Users (NCT NCT04003805)

NCT ID: NCT04003805

Last Updated: 2026-01-29

Results Overview

Cotinine (biomarker of nicotine) level after switching to SREC as percentage of baseline level

• Recruitment status: ACTIVE_NOT_RECRUITING
• Study phase: PHASE1
• Target enrollment: 47 participants
• Primary outcome timeframe: 6 weeks
• Results posted on: 2026-01-29

Participant Flow

Participant milestones

Measure	Switching From Smoking Cigarettes to SREC Standardized Research E-cigarette (SREC): The device operates using a rechargeable 400 mAh lithium-ion battery and uses sealed disposable 1.9-mL pods with e-liquid containing 5% w/w nicotine. Flavors that will be available include tobacco, menthol, watermelon and blueberry. The device uses a battery that can be recharged via a micro USB port. The e-liquid and the aerosol are well-characterized in terms of chemical impurities and by-products (such as aldehydes), which are minimal.
Overall Study STARTED	47
Overall Study COMPLETED	23
Overall Study NOT COMPLETED	24

Reasons for withdrawal

Measure	Switching From Smoking Cigarettes to SREC Standardized Research E-cigarette (SREC): The device operates using a rechargeable 400 mAh lithium-ion battery and uses sealed disposable 1.9-mL pods with e-liquid containing 5% w/w nicotine. Flavors that will be available include tobacco, menthol, watermelon and blueberry. The device uses a battery that can be recharged via a micro USB port. The e-liquid and the aerosol are well-characterized in terms of chemical impurities and by-products (such as aldehydes), which are minimal.
Overall Study Lost to Follow-up	5
Overall Study Physician Decision	11
Overall Study Withdrawal by Subject	8

Baseline Characteristics

Biomarkers of Exposure and Effect in Standardized Research E-cigarette (SREC) Users

Baseline characteristics by cohort

Measure	Switching From Smoking Cigarettes to SREC n=47 Participants Standardized Research E-cigarette (SREC): The device operates using a rechargeable 400 mAh lithium-ion battery and uses sealed disposable 1.9-mL pods with e-liquid containing 5% w/w nicotine. Flavors that will be available include tobacco, menthol, watermelon and blueberry. The device uses a battery that can be recharged via a micro USB port. The e-liquid and the aerosol are well-characterized in terms of chemical impurities and by-products (such as aldehydes), which are minimal.
Age, Categorical <=18 years	0 Participants n=35 Participants
Age, Categorical Between 18 and 65 years	47 Participants n=35 Participants
Age, Categorical >=65 years	0 Participants n=35 Participants
Sex: Female, Male Female	27 Participants n=35 Participants
Sex: Female, Male Male	20 Participants n=35 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=35 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	46 Participants n=35 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=35 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=35 Participants
Race (NIH/OMB) Asian	1 Participants n=35 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=35 Participants
Race (NIH/OMB) Black or African American	1 Participants n=35 Participants
Race (NIH/OMB) White	43 Participants n=35 Participants
Race (NIH/OMB) More than one race	1 Participants n=35 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=35 Participants
Region of Enrollment United States	47 participants n=35 Participants

PRIMARY outcome

Timeframe: 6 weeks

Cotinine (biomarker of nicotine) level after switching to SREC as percentage of baseline level

Outcome measures

Measure	Switching From Smoking Cigarettes to SREC n=23 Participants Participants who smoked at baseline were asked to completely switch to SREC e-cigarette for 6 weeks.
Exposure Biomarkers: Cotinine	98.5 Percentage of baseline level Standard Deviation 51.1

PRIMARY outcome

Timeframe: 6 weeks

Total NNAL level after switching to SREC as percentage of baseline level

Outcome measures

Measure	Switching From Smoking Cigarettes to SREC n=23 Participants Participants who smoked at baseline were asked to completely switch to SREC e-cigarette for 6 weeks.
Exposure Biomarkers: NNAL	53.7 Percentage of baseline level Standard Deviation 40.8

PRIMARY outcome

Timeframe: 6 weeks

CEMA level after switching to SREC as percentage of baseline level

Outcome measures

Measure	Switching From Smoking Cigarettes to SREC n=23 Participants Participants who smoked at baseline were asked to completely switch to SREC e-cigarette for 6 weeks.
Exposure Biomarkers: CEMA	15.0 Percentage of baseline level Standard Deviation 20.2

PRIMARY outcome

Timeframe: 6 weeks

3-HPMA level after switching to SREC as percentage of baseline level

Outcome measures

Measure	Switching From Smoking Cigarettes to SREC n=23 Participants Participants who smoked at baseline were asked to completely switch to SREC e-cigarette for 6 weeks.
Exposure Biomarkers: 3-HPMA	38.5 Percentage of baseline level Standard Error 35.7

PRIMARY outcome

Timeframe: 6 weeks

Urinary isoprostane level after switching to SREC as percentage of baseline level

Outcome measures

Measure	Switching From Smoking Cigarettes to SREC n=23 Participants Participants who smoked at baseline were asked to completely switch to SREC e-cigarette for 6 weeks.
Inflammatory Biomarkers	88.3 Percentage of baseline level Standard Deviation 52.6

PRIMARY outcome

Timeframe: 6 weeks

Population: Only 11 subjects analyzed. Remaining subjects did not have sufficient sample volume for specific analysis.

Levels of NNN in saliva after switching to SREC

Outcome measures

Measure	Switching From Smoking Cigarettes to SREC n=11 Participants Participants who smoked at baseline were asked to completely switch to SREC e-cigarette for 6 weeks.
Salivary Biomarkers	229.7 pg/mL Saliva Standard Deviation 640

SECONDARY outcome

Timeframe: 1 Year

For cigarettes, cigarettes per day will be assessed based on Interactive Voice Response (IVR) system.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 1 Year

The number of cigarette avoidance days, defined as no tobacco cigarettes smoked in the past 24 hours based on IVR, and the rate of cigarette avoidance, calculated as the proportion of cigarette avoidance days out of the total number of days in the product use period (56 days for those who complete the study).

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 1 Year

Urinary total NNN level (TSNA biomarker) after switching to SREC as percentage of baseline level

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 1 Year

Urinary level of 1-HOP (PAH biomarker) after switching to SREC as percentage of baseline level

Outcome measures

Outcome data not reported

Adverse Events

Switching From Smoking Cigarettes to SREC

Serious events: 5 serious events

Other events: 28 other events

Deaths: 0 deaths

Serious adverse events

Measure	Switching From Smoking Cigarettes to SREC n=47 participants at risk Standardized Research E-cigarette (SREC): The device operates at a single output voltage (3.30 ± 0.05 V) and uses sealed disposable 3-mL cartridges with tobacco-flavored e-liquid (\~350 puffs/cartridge). The concentration of nicotine in e-liquid is 15 mg/mL, and the vehicle composition is 50:50 propylene glycol and glycerin. The device uses a battery that can be recharged via a micro USB port. A single charge is designed to sustain more than 400 puffs, which is more than the capacity of an e-liquid cartridge. The e-liquid and the aerosol are well-characterized in terms of chemical impurities and by-products (such as aldehydes), which are minimal. Additional information, including the results of pharmacokinetics study is available via NIDA website: https://www.drugabuse.gov/funding/supplemental-information-nida-e-cig
Vascular disorders Thromboembolic event (DVT/pulmonary embolism)	2.1% 1/47 • Number of events 1 • 1 year
Respiratory, thoracic and mediastinal disorders Cancer, Lung	2.1% 1/47 • Number of events 1 • 1 year
Injury, poisoning and procedural complications Head Injury - Accident	2.1% 1/47 • Number of events 1 • 1 year
Infections and infestations Pneumonitis (pneumonia)	2.1% 1/47 • Number of events 1 • 1 year
Cardiac disorders Cardiomyopathy	2.1% 1/47 • Number of events 1 • 1 year

Other adverse events

Measure	Switching From Smoking Cigarettes to SREC n=47 participants at risk Standardized Research E-cigarette (SREC): The device operates at a single output voltage (3.30 ± 0.05 V) and uses sealed disposable 3-mL cartridges with tobacco-flavored e-liquid (\~350 puffs/cartridge). The concentration of nicotine in e-liquid is 15 mg/mL, and the vehicle composition is 50:50 propylene glycol and glycerin. The device uses a battery that can be recharged via a micro USB port. A single charge is designed to sustain more than 400 puffs, which is more than the capacity of an e-liquid cartridge. The e-liquid and the aerosol are well-characterized in terms of chemical impurities and by-products (such as aldehydes), which are minimal. Additional information, including the results of pharmacokinetics study is available via NIDA website: https://www.drugabuse.gov/funding/supplemental-information-nida-e-cig
Cardiac disorders Chest Pain - Cardiac / Angina	4.3% 2/47 • Number of events 2 • 1 year
Cardiac disorders Tachycardia / Fast heart rate	2.1% 1/47 • Number of events 1 • 1 year
Eye disorders Eye Pain (incl: dry/irritation/itchy/watery)	2.1% 1/47 • Number of events 1 • 1 year
Investigations Periodontal Problem (Gums)	2.1% 1/47 • Number of events 2 • 1 year
General disorders Vomiting	2.1% 1/47 • Number of events 1 • 1 year
General disorders Nausea	2.1% 1/47 • Number of events 1 • 1 year
General disorders Diarrhea	4.3% 2/47 • Number of events 2 • 1 year
General disorders Tooth Loss	2.1% 1/47 • Number of events 1 • 1 year
Skin and subcutaneous tissue disorders Cold/clammy/pale skin	2.1% 1/47 • Number of events 1 • 1 year
General disorders Fatigue	4.3% 2/47 • Number of events 2 • 1 year
Musculoskeletal and connective tissue disorders Joint Pain	2.1% 1/47 • Number of events 1 • 1 year
General disorders Vivid Dreams (see S for nightmare/terror)	2.1% 1/47 • Number of events 1 • 1 year
Infections and infestations Bronchial Infection	2.1% 1/47 • Number of events 1 • 1 year
Infections and infestations COVID-19 (Tested + or presumed dx by PCP)	4.3% 2/47 • Number of events 2 • 1 year
Metabolism and nutrition disorders Fracture	2.1% 1/47 • Number of events 1 • 1 year
General disorders Dehydration	2.1% 1/47 • Number of events 1 • 1 year
Musculoskeletal and connective tissue disorders Arthritis	2.1% 1/47 • Number of events 1 • 1 year
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Benign Cyst/Mass/Polyp	4.3% 2/47 • Number of events 2 • 1 year
Investigations Dizziness/Lightheadedness	4.3% 2/47 • Number of events 2 • 1 year
General disorders Headache (incl. migraine)	8.5% 4/47 • Number of events 7 • 1 year
General disorders Depressed (sad) mood	14.9% 7/47 • Number of events 7 • 1 year
Immune system disorders Allergic rhinitis (incl. seasonal allergies)	8.5% 4/47 • Number of events 4 • 1 year
Investigations Cough	21.3% 10/47 • Number of events 11 • 1 year
General disorders Nasal congestion (incl. runny nose)	8.5% 4/47 • Number of events 4 • 1 year
General disorders Nosebleed / Dry nasal membrane	2.1% 1/47 • Number of events 1 • 1 year
Respiratory, thoracic and mediastinal disorders Shortness of Breath	4.3% 2/47 • Number of events 2 • 1 year
Skin and subcutaneous tissue disorders Rash	2.1% 1/47 • Number of events 1 • 1 year
General disorders Stress	2.1% 1/47 • Number of events 1 • 1 year
Cardiac disorders Hypertension / Elevated BP	6.4% 3/47 • Number of events 3 • 1 year
Cardiac disorders Hypotension / Low BP	2.1% 1/47 • Number of events 1 • 1 year

Additional Information

Irina Stepanov, PhD

Masonic Cancer Center

Phone: 612-624-4998

Email: stepa011@umn.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place