Cannabis and Tobacco Co-use Study

NCT ID: NCT04228965

Last Updated: 2025-06-15

Study Results

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Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

PHASE4

Total Enrollment

181 participants

Study Classification

INTERVENTIONAL

Study Start Date

2020-01-28

Study Completion Date

2024-09-13

Brief Summary

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The purpose of this study is to better understand tobacco outcomes using a well-known stop smoking medication, varenicline, and financial incentives with tobacco users. The investigators are also interested in how cannabis/marijuana and tobacco interact during a tobacco quit attempt. All participants will receive tobacco cessation treatment (varenicline) for 12 weeks. This study will recruit adult tobacco users (ages 18-40) who are motivated to quit smoking cigarettes.

Detailed Description

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Cannabis co-use among tobacco users is exceedingly common and rates of co-use appear to be increasing among adults in the US, which is consistent with overall increases in cannabis use rates among US adults. Given the current cannabis landscape, further increases in cannabis use are likely and may result in continued increases in the co-use of cannabis and tobacco.

Despite high rates of co-use, there is little consensus regarding treatment recommendations for this population and an understanding of the impact of co-use on successful cessation. The literature on the impact of co-use on tobacco cessation outcomes specifically has been mixed and fraught with limitations, including methodological variation, lack of biochemical verification to confirm cannabis use status and severity, and variations in study samples. Currently, no prospective studies have been conducted to evaluate the impact of cannabis use on tobacco cessation outcomes. Further, no studies have collected cannabis use changes during tobacco cessation treatment to assess for concurrent reductions, abstinence, or of greater concern, compensatory (i.e., increased) use as a result of tobacco reduction/abstinence.

This study is a prospective 12-week tobacco cessation trial using established methods and outcomes typical of tobacco cessation trials, but specifically recruiting co-users of cannabis. The aims of this proposed study are to; 1) examine the impact of cannabis co-use on tobacco cessation outcomes among co-users compared to tobacco only participants (Aim #1), 2) among cannabis co-users, assess changes in cannabis use during tobacco treatment (Aim #2), and 3) assess for a dose-dependent impact of cannabis co-use severity on tobacco cessation (Exploratory Aim #1).

Conditions

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Tobacco Use Disorder

Study Design

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Allocation Method

NON_RANDOMIZED

Intervention Model

SINGLE_GROUP

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

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Co-Use Group

Cannabis and tobacco co-use group.

Group Type OTHER

Varenicline

Intervention Type DRUG

Varenicline is a medication approved by the Food and Drug Administration for the treatment of tobacco use disorder among adults (ages 18 and over). In this study, all participants will be administered active medication for the recommended 12 week treatment period. The standard dose titration schedule will be used, which includes 0.5 mg once per day (q.d.) on Days 1-3, 0.5 mg twice per day (b.i.d.) on Days 4-7, and 1.0 mg b.i.d. starting on Day 8. Dosing of 2.0 mg per day will be maintained for the next 11 weeks, for a total of 12 weeks of active treatment for all study participants.

Contingency Management

Intervention Type BEHAVIORAL

Contingency management procedures will be implemented and financial incentives will be provided at weekly visits contingent on tobacco abstinence verified through urinary qualitative cotinine (starting at Week 2). A set amount of $20 per study visit will be delivered based on a negative qualitative urinary cotinine result.

Counseling

Intervention Type BEHAVIORAL

Psychosocial counseling will be administered by trained research staff leading up to the target quit date and throughout the study. Counseling will include motivational enhancement for medication adherence and tobacco cessation. The content of counseling will be skills-based and will focus on enlisting social support, recognizing smoking triggers, managing craving/withdrawal/stress, etc.

Tobacco Only Group

Tobacco only group.

Group Type ACTIVE_COMPARATOR

Varenicline

Intervention Type DRUG

Varenicline is a medication approved by the Food and Drug Administration for the treatment of tobacco use disorder among adults (ages 18 and over). In this study, all participants will be administered active medication for the recommended 12 week treatment period. The standard dose titration schedule will be used, which includes 0.5 mg once per day (q.d.) on Days 1-3, 0.5 mg twice per day (b.i.d.) on Days 4-7, and 1.0 mg b.i.d. starting on Day 8. Dosing of 2.0 mg per day will be maintained for the next 11 weeks, for a total of 12 weeks of active treatment for all study participants.

Contingency Management

Intervention Type BEHAVIORAL

Contingency management procedures will be implemented and financial incentives will be provided at weekly visits contingent on tobacco abstinence verified through urinary qualitative cotinine (starting at Week 2). A set amount of $20 per study visit will be delivered based on a negative qualitative urinary cotinine result.

Counseling

Intervention Type BEHAVIORAL

Psychosocial counseling will be administered by trained research staff leading up to the target quit date and throughout the study. Counseling will include motivational enhancement for medication adherence and tobacco cessation. The content of counseling will be skills-based and will focus on enlisting social support, recognizing smoking triggers, managing craving/withdrawal/stress, etc.

Interventions

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Varenicline

Varenicline is a medication approved by the Food and Drug Administration for the treatment of tobacco use disorder among adults (ages 18 and over). In this study, all participants will be administered active medication for the recommended 12 week treatment period. The standard dose titration schedule will be used, which includes 0.5 mg once per day (q.d.) on Days 1-3, 0.5 mg twice per day (b.i.d.) on Days 4-7, and 1.0 mg b.i.d. starting on Day 8. Dosing of 2.0 mg per day will be maintained for the next 11 weeks, for a total of 12 weeks of active treatment for all study participants.

Intervention Type DRUG

Contingency Management

Contingency management procedures will be implemented and financial incentives will be provided at weekly visits contingent on tobacco abstinence verified through urinary qualitative cotinine (starting at Week 2). A set amount of $20 per study visit will be delivered based on a negative qualitative urinary cotinine result.

Intervention Type BEHAVIORAL

Counseling

Psychosocial counseling will be administered by trained research staff leading up to the target quit date and throughout the study. Counseling will include motivational enhancement for medication adherence and tobacco cessation. The content of counseling will be skills-based and will focus on enlisting social support, recognizing smoking triggers, managing craving/withdrawal/stress, etc.

Intervention Type BEHAVIORAL

Other Intervention Names

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Chantix

Eligibility Criteria

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Inclusion Criteria

1. Between the ages of 18 and 40 years old
2. Must be able to understand the study and provide written informed consent
3. Daily cigarette smoker for ≥ 6 months, smoking ≥ 5 cigarettes per day
4. Must submit a breath carbon monoxide (CO) sample of ≥ 7 parts per million (ppm) at the screening visit
5. Be interested in quitting smoking tobacco cigarettes (defined as a 5 or above on a 10-point Likert scale assessing interest in quitting \[1=not at all interested, 10=extremely interested\])
6. Must be willing to take varenicline for the standard 12-week course of treatment
7. If female, agreement to use birth control (any form) to avoid pregnancy during study procedures

8. Self-reported use of cannabis on at least 10 out of the past 30 days or submit a positive qualitative urinary cannabinoid test at screening (limit of detection is 50 ng/ml)

Exclusion Criteria

1. Any serious or unstable medical/psychiatric disorder (including severe substance use disorders, other than cannabis or tobacco use disorders) or other significant concern in the past three months that may interfere with study performance, impact participant safety, compliance with study procedures, or potentially confound the interpretation of findings
2. Currently pregnant, lactating, or contemplating pregnancy in the next 6 months
3. Current use of medications with smoking cessation efficacy
4. Use of any medications that would interfere with varenicline
5. No regular use of other tobacco or nicotine products other than combustible cigarettes (e.g., smokeless tobacco, electronic cigarettes, etc.) in the past month prior to the quit attempt
Minimum Eligible Age

18 Years

Maximum Eligible Age

40 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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National Cancer Institute (NCI)

NIH

Sponsor Role collaborator

National Institutes of Health (NIH)

NIH

Sponsor Role collaborator

Medical University of South Carolina

OTHER

Sponsor Role lead

Responsible Party

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Erin McClure

Principal Investigator

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

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Erin McClure, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

Medical University of South Carolina

Locations

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Medical University of South Carolina - Charleston

Charleston, South Carolina, United States

Site Status

Medical University of South Carolina - Florence

Florence, South Carolina, United States

Site Status

Behavioral Health Services of Pickens County

Pickens, South Carolina, United States

Site Status

Countries

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United States

References

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Walters KJ, Baker NL, Tomko RL, Gray KM, Carpenter MJ, McClure EA. Determining the impact of cannabis use and severity on tobacco cessation outcomes: study protocol for a prospective tobacco treatment trial. BMC Psychol. 2023 Jan 25;11(1):25. doi: 10.1186/s40359-023-01060-2.

Reference Type DERIVED
PMID: 36698194 (View on PubMed)

Provided Documents

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Document Type: Study Protocol and Statistical Analysis Plan

View Document

Document Type: Informed Consent Form

View Document

Other Identifiers

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R37CA237245

Identifier Type: NIH

Identifier Source: secondary_id

View Link

00086954

Identifier Type: -

Identifier Source: org_study_id

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