Are Smokers Switching to Vaping at Lower Risk for Cancer? (Electronic Cigarettes and Cancer Risk)

August 1, 2025 updated by: Ahmad Besaratinia, University of Southern California

Are Smokers Switching to Vaping at Lower Risk for Cancer?

This project will address a growing public health concern, namely, the health risks or benefits of e-cig use relative to cigarette smoking. The investigators will use biomarkers of early effects of relevance to cancer to determine the carcinogenic potential of e-cig use relative to cigarette smoking in oral epithelium, which is a target tissue for smoking-associated cancer. The study population will consist of one group of smokers who are interested in switching to e-cig use (Grp 1), one group of smokers who do not intend to change their smoking habits (Grp 2), and one group of non-users who would like to maintain their nonsmoking non-vaping status (Grp 3); The total number of participants in this project is 150 (n = 50, each group). The investigators will use an integrative 'multi-omics' approach complemented with single-locus/gene validation analyses to detect temporal changes in the genome, epigenome, and transcriptome relevant to cancer in the oral cells of the participants as the intervention progresses.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Electronic cigarettes (e-cig) are increasingly popular among adult smokers and adolescent never smokers. Chemical analyses of e-cig vapor and liquid have shown the presence of many of the same carcinogens as those found in cigarette smoke, albeit in generally lower concentrations. However, the carcinogenic potential of e-cig has not been investigated in e-cig users (otherwise known as 'vapers'). The investigators will investigate the cancer-causing potential of e-cig use as compared to cigarette smoking by quantifying molecular changes linked to risk of cancer in smokers who switch to e-cig use vs. those who maintain their smoking habits. Leveraging a source population for ongoing studies on e-cig, the investigators will recruit smokers who are interested in switching to e-cig use, and two control groups of non-vapers, including smokers and nonsmokers who do not intend to change their smoking and nonsmoking status, respectively (n = 50, each group). Smokers consenting to switch completely to e-cig will be assigned to a 3-month intervention with a standard e-cig with fully described product characteristics. Control groups will maintain their smoking/nonsmoking habits during the intervention. At weekly intervals, the investigators will verify participants' compliance through personal interviews, CO breath tests, cotinine quantification, and vaping/smoking topography measurements. The investigators will use a non-invasive brushing technique to collect oral cells from the inside of the cheeks of all participants at baseline and every 2 weeks, afterwards. The investigators will use an integrative 'multi-omics' approach complemented with single-locus/gene validation analyses to detect temporal changes in the genome, epigenome, and transcriptome relevant to cancer in the oral cells of the participants as the intervention progresses.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
150

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • California
      • Los Angeles, California, United States, 90033
        • University of Southern California, Health Sciences Campus

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

22 years to 55 years (Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Being male or female between the ages of 22-55;
  • Being able to read and write in English and understand and give informed consent;
  • Giving consent to strictly follow the study protocol throughout the study;
  • Not planning to move, take an extended vacation, or undergo surgery during the study;
  • Reporting smoking of > 5 manufactured cigarettes per day for at least 1 year (applicable to participants who will undergo intervention with e-cig (Grp 1) or continue to smoke (Grp 2) only); and
  • Presenting with an expired air CO measurement of > 7 parts per million (ppm) at baseline (applicable to participants who will undergo intervention with e-cig (Grp 1) or continue to smoke (Grp 2) only).

Exclusion Criteria:

  • Having oral infection/inflammation, gum disease, dental decay, immune system disorders, diabetes, respiratory diseases (e.g., asthma), or kidney diseases;
  • Having any unstable or significant medical condition (e.g., symptomatic heart conditions) in the past 12 months ;
  • Having body mass index < 18 kg/m2 or > 40 kg/m2
  • Being pregnant or having a baby in the past 12 months;
  • Having uncontrolled mental illness or substance abuse (e.g., alcoholism) or inpatient treatment for those conditions in the past 12 months;
  • Having used recreational or illicit drugs in the past 3 months;
  • Having used any medication known to induce/inhibit CYP450 2A6 enzyme;
  • Having any known allergy to propylene glycol/vegetable glycerin (applicable participants who will undergo intervention with e-cig (Grp 1) only); and
  • Having another member of household participating in the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Vapers
Smokers will switch to NIDA Standard Research E-cigarette (SREC).
Device: NIDA Standard Research E-cigarette (SREC)
Smokers will switch to NIDA Standard Research E-cigarette (SREC).
No Intervention: Smokers
Smokers will continue to smoke.
No Intervention: Nonsmokers non-vapers
Control nonsmokers non-vapers will continue to refrain from smoking or vaping.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Genetic changes
Time Frame: 3 months
Number and location of DNA damage
3 months
Epigenetic changes
Time Frame: 3 months
Number of epigenetic marks
3 months

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Gene expression
Time Frame: Every 2 weeks for 3 months
Relative gene expression
Every 2 weeks for 3 months
DNA methylation
Time Frame: Every 2 weeks for 3 months
Pattern and distribution of aberrant DNA methylation
Every 2 weeks for 3 months
Histone modifications
Time Frame: Every 2 weeks for 3 months
Pattern and distribution of histone marks
Every 2 weeks for 3 months
Mutation
Time Frame: Every 2 weeks for 3 months
Frequency and location of mutations
Every 2 weeks for 3 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Southern California

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
University of California

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Ahmad Besaratinia, University of Southern California

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
December 1, 2021

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
July 31, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
July 31, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 16, 2018

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 21, 2018

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 23, 2018

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 6, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 1, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2025

More Information

Terms related to this study

Keywords

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • HS-18-00744

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

There is no plan to make individual participant data (IPD) available to other researchers.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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