E-cigarette Cessation in Adults Who Co-use Cannabis

NCT ID: NCT06688539

Last Updated: 2025-07-07

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: PHASE4
• Total Enrollment: 105 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-02-19
• Study Completion Date: 2026-09-01

Brief Summary

The purpose of this study is to better understand tobacco outcomes using a commonly prescribed stop smoking medication (varenicline) and financial incentives for adults who also use cannabis. Varenicline is not FDA approved for e-cigarette cessation, but is FDA approved for cigarette cessation. Investigators are also interested in how cannabis/marijuana and tobacco interact during a tobacco quit attempt. All participants will receive e-cigarette cessation treatment for 12 weeks. To qualify, participants must be between the ages of 18-40 and use both e-cigarettes and cannabis. Participants do not need to be interested in quitting cannabis to qualify. This study is being conducted at three sites: the Medical University of South Carolina in Charleston, SC, Behavioral Health Services in Pickens, SC, and MUSC Lancaster in Lancaster, SC.

Detailed Description

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; Specific Aim 1. Compare rates of 7-day biochemically-confirmed e-cigarette abstinence with cigarette abstinence rates from the parent R37 co-use sample (as a historical controls). Specific Aim 2. Assess changes in cannabis use during e-cigarette cessation treatment among the new sample of participants enrolled in this extension.

Specific Aim 3. Assess for a dose-dependent impact of cannabis co-use severity on e-cigarette cessation. Specific Aim 4. Characterize and compare patterns of co-use among the e-cigarette sample to those using cigarettes (parent R37).

Conditions

Nicotine Dependence; Tobacco Use Disorder

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Co-use group

E-cigarette and cannabis co-use group

Group Type: OTHER

Varenicline Pill

Intervention Type: DRUG

In this study, all participants will be administered active medication for a 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 e-cigarette 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.

Interventions

Varenicline Pill

In this study, all participants will be administered active medication for a 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 e-cigarette 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.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Between the ages of 18 and 40 years old
• Use e-cigarettes daily or near daily in the past month
• Must submit a positive instant-read urine cotinine test at screening (≥ 200 ng/ml)
• Be interested in quitting use of e-cigarettes
• Must be willing to take varenicline for the standard 12-week course of treatment
• Self-reported use of cannabis on at least 10 out of the past 30 days or must submit a positive qualitative urinary cannabinoid test at screening (> 50 ng/ml)

Exclusion Criteria

• Any serious or unstable medical/psychiatric disorder (including severe substance use disorders, other than cannabis or tobacco use disorders) in the past three months that may interfere with study performance
• Use of cigarettes on 10+ days in the past 30
• Currently pregnant or breastfeeding
• Current use of medications with smoking cessation efficacy
• Use of any medications that would interfere with varenicline

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 40 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Cancer Institute (NCI)

NIH

Sponsor Role: collaborator

Medical University of South Carolina

OTHER

Sponsor Role: lead

Responsible Party

Erin McClure

Associate Professor-Faculty

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Erin A McClure, PhD

Role: PRINCIPAL_INVESTIGATOR

Medical University of South Carolina

Locations

MUSC Charleston

Charleston, South Carolina, United States

Site Status: RECRUITING

MUSC Lancaster

Lancaster, South Carolina, United States

Site Status: RECRUITING

Behavioral Health Services of Pickens County

Pickens, South Carolina, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Elizabeth Chapman, MA, LPC, LAC, AADC

Role: CONTACT

chapmanb@musc.edu

864.898.2992

Facility Contacts

Ela Williams

Role: primary

williela@musc.edu

843-497-4092

Frances Hakes

Role: primary

hakesf@musc.edu

864-898-2992

Elizabeth Chapman, LPC

Role: primary

chapmanb@musc.edu

864-898-2992

Other Identifiers

R37CA237245

Identifier Type: NIH

Identifier Source: secondary_id

View Link

Pro00136601

Identifier Type: -

Identifier Source: org_study_id