Dual Use Cessation: A MOST Screening Trial to Identify Effective Interventions to Help People Who Smoke and Vape

To be efficient and maximize translation potential, the investigators will use the efficient Multiphase Optimization Strategy (MOST) to identify an optimal intervention to help people who use both cigarettes and ENDS quit smoking cigarettes. As such, in this randomized 2x2x2 factorial screening trial, the investigators will examine three intervention components:

1. Pharmacotherapy (varenicline vs. nicotine patch)
2. Counseling Intensity (4 vs. 1 session)
3. Counseling Approach (Dual Focused vs. Smoking Focused).

The Dual Focused counseling approach will encourage participants to quit their ENDS use as part of their smoking cessation attempt. The Smoking Focused counseling approach will encourage participants to quit smoking but not vaping and to use their ENDS strategically to deal with urges in service of harm reduction. There is theoretical and empirical support for these pharmacologic and counseling approaches and intensities.

Participants (N=500) will be dual users of cigarettes (>4 cigs/day for the last 6 months) and ENDS (vape weekly for at least 6 months) who are motivated to quit smoking and willing try to quit vaping, if asked to do so. Participants will be recruited, assessed, and treated remotely. They will be randomized to receive either varenicline or nicotine patches for 12 weeks, to receive either one or four 15-20-minute counseling sessions, and to receive counseling that is either dual focused or smoking focused. Dual Focused Cessation will focus on quitting both smoking and vaping on the target quit date (TQD). Pre-TQD, participants will be instructed to change smoking and vaping patterns (e.g., not smoking or vaping in specific places or at specific times of day). Post-TQD, participants will focus on building smoking and vaping cessation skills (e.g., coping with cravings to smoke or vape, avoiding smoking and vaping cues). Smoking Focused Cessation will focus on quitting smoking on the TQD and using ENDS as a behavioral substitute (i.e., using ENDS as a cigarette substitute). Pre-TQD, participants will be instructed to change smoking patterns (e.g., vaping rather than smoking in specific places or at specific times of day, vaping first in the morning rather than smoking) and practice smoking cessation coping strategies (e.g., substituting ENDS for cigarettes, avoiding smoking cues). Participants will be advised to quit smoking on the TQD and not worry about quitting vaping at this point. Participants will complete daily measures of smoking, vaping, and potential change mechanisms (e.g., craving, smoking reward, self-efficacy) via ecological momentary assessment (EMA) for 2 weeks pre-TQD and 2 weeks post-TQD. Follow-up will occur for 12 months post-TQD.

Primary Objective: Determine which pharmacologic and counseling approaches are especially effective, alone or in combination, in helping dual users quit smoking.