Metabolism-informed Care for Smoking Cessation

December 30, 2025 updated by: Hilary Tindle, Vanderbilt University Medical Center
Nicotine mediates smoking's addictive effects in the brain. The ratio of 3-hydroxycotinine to cotinine, known as the nicotine metabolite ratio, or NMR, is a genetically- informed biomarker reflecting hepatic CYP2A6 activity and the rate of nicotine metabolism. In light of a recent randomized controlled trial (RCT) in humans in Lancet Respiratory Medicine, which found that the NMR can be used to individualize treatment for smokers, our pilot study aims to determine the feasibility of using NMR to guide selection of pharmacotherapy in clinical populations of daily smokers.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

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

Consenting participants will be assigned to guideline-based care (GBC: incorporating national guidelines and more recent evidence from clinical trials of pharmacotherapy for smoking cessation) or metabolism-informed care (MIC: identical to GBC but selection of medication based on NMR result). All participants received counseling from a nurse level certified tobacco counseling. After consent, participants undergo a blood draw for NMR, complete a baseline questionnaire, and are randomized to GBC or MIC. At approximately 1, 3, and 6 months post-consent, participants will provide follow up information via telephone questionnaire regarding symptoms, confidence in quitting, use of medications, and smoking status. At the 6-month follow-up time point, if a participant self-reports abstinence from smoking, the participant will be asked to complete a survey in-person and provide a sample of end-expired carbon monoxide for biochemical validation. At the 6 month time point, GBC participants who continue to smoke will be offered an additional phone call from the nurse tobacco counselor in which the results of the baseline NMR test will be given, along with a second prescription for a smoking cessation medication based on the NMR results (i.e., single arm crossover design). Two weeks after this additional phone call, the patient will be contacted for a final survey regarding use of medication and smoking status.

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 (Actual)

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.
82

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

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

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • 18 years or older
  • Smokes ≥ 5 cigarettes per day
  • Willing to give up all forms of tobacco (5/10/2016 - 6/27/2016)
  • Medically cleared (i.e., no contraindications in Section 3) to receive at least 2 FDA- approved smoking cessation medications
  • Willing to use the medications for which medically cleared (individually, not in combination; only applicable if Medically Cleared = Yes)

Exclusion Criteria:

  • Current diagnosis of schizophrenia, psychosis, active suicidal ideation, dementia, or severe mental retardation
  • Receiving palliative or hospice care
  • Currently pregnant or breastfeeding
  • Hospitalized for a psychiatric condition in the past year (5/10/2016 - 6/27/2016)
  • Hospitalized for a psychiatric condition in the past 3 months or change in psychiatric medications in last 3 months (6/28/2016 forward)
  • Telephone problems that would preclude participation (e.g., can't receive calls reliably)
  • Not able to read and speak English
  • Abstinent from cigarettes for >3 days (b/c NMR not reliable after 72 hours)
  • Used smoking cessation medications in the last 7 days (5/10/2016 - 6/27/2016)

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: Health Services Research
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Triple

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.
Active Comparator: Metabolism-Informed Care (MIC)
Smoking Cessation Pharmacotherapy (varenicline, bupropion, and nicotine patch) recommendations were guided by Nicotine Metabolism as measured by the Nicotine Metabolite Ratio. Ultimately, after being educated about smoking cessation medication efficacy and side-effects, the participant could decide to take any medication for which they were medically cleared, but the recommendation was made based on rate of Nicotine Metabolism.
Other: Nicotine Metabolite Ratio
This intervention used information from a genetically-informed biomarker (Nicotine Metabolite Ratio, NMR) to assign one of 3 FDA-approved smoking cessation pharmacotherapies (varenicline, bupropion, or NRT) to participants.
Drug: Varenicline
FDA-approved smoking cessation pharmacotherapy
Other Names:
  • Chantix
Drug: Bupropion
FDA-approved smoking cessation pharmacotherapy
Other Names:
  • Zyban
Drug: Nicotine patch
FDA-approved smoking cessation pharmacotherapy
Other Names:
  • Nicotine Replacement Therapy (NRT)
Active Comparator: Guideline-Based Care (GBC)
Smoking Cessation Pharmacotherapy (varenicline, bupropion, and nicotine patch) was co-selected from those they were medically able to receive after educating participants about smoking cessation medication efficacy and side-effects.
Drug: Varenicline
FDA-approved smoking cessation pharmacotherapy
Other Names:
  • Chantix
Drug: Bupropion
FDA-approved smoking cessation pharmacotherapy
Other Names:
  • Zyban
Drug: Nicotine patch
FDA-approved smoking cessation pharmacotherapy
Other Names:
  • Nicotine Replacement Therapy (NRT)

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
Theoretical Endorsement of MIC as assessed by level of agreement to a set of seven 5-point Likert Scale questions
Time Frame: Baseline
Likert Scale from Strongly Disagree to Strongly Agree on items assessing attitudes toward and perceptions of using metabolism information to guide medical care
Baseline
Acceptance of MIC medication recommendation as assessed by concordance between MIC recommendation and actual prescribed medication
Time Frame: At 4 weeks post-baseline
Level of agreement between participant's prescribed medication and the medication that would be recommended based on Nicotine Metabolite Ratio
At 4 weeks post-baseline

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
Confidence in Quitting
Time Frame: Baseline - 6 months
Self-reported confidence in ability to quit
Baseline - 6 months
Medication Use/Compliance
Time Frame: 1 - 6 months
Use of prescribed medication, as directed
1 - 6 months
Smoking Status
Time Frame: 6 months
Self-reported and/or biochemically validated smoking cessation
6 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.
Vanderbilt University Medical Center

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: Quinn Wells, MD, Vanderbilt University Medical Center
  • Principal Investigator: Dawn Beaulieu, MD, Vanderbilt University Medical Center
  • Principal Investigator: Matthew Freiberg, MD, Vanderbilt University Medical Center
  • Principal Investigator: Hilary Tindle, MD, Vanderbilt University Medical Center

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

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.
May 18, 2016

Primary Completion (Actual)

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.
October 8, 2016

Study Completion (Actual)

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.
April 18, 2017

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).
June 29, 2017

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.
July 20, 2017

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.
July 24, 2017

Study Record Updates

Last Update Posted (Estimated)

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.
January 6, 2026

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.
December 30, 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.
December 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

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.
  • 160512

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

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.

Clinical Trials on Tobacco Use

Clinical Trials on Nicotine Metabolite Ratio

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings