Investigating Efficacious E-Cigarette Interventions and Cessation Effects on Cancer-Related Biomarkers: A Randomized Trial of Varenicline in Adults

Participants will randomly be assigned to 12-weeks of varenicline (titrated to 2mg daily) or matching placebo plus brief cessation advice from a counselor and self-management resources. All participants will also complete research assessments every 3 weeks during treatment and a final follow-up visit at week 26. The primary objective is to test the efficacy of varenicline vs. placebo on e-cigarette quit rates. We will also evaluate predictors and moderators of outcomes and explore changes in health biomarkers following e-cigarette cessation treatment.