Varenicline for Nicotine Vaping Cessation in Adolescents

The study will test the hypothesis that varenicline, when added to behavioral and texting support for vaping cessation, will improve vaping abstinence rates in adolescents dependent on vaped nicotine over placebo plus behavioral and texting support for vaping cessation. Approximately 225 adolescents will be randomly assigned to one of three arms (1) varenicline up to 1 mg bid for 12 weeks plus behavioral and texting support for vaping cessation (V+BC), (2) identical appearing placebo plus behavioral and texting support (P+BC) and (3) enhanced usual care (EUC). The primary comparison will be the double-blind, placebo-controlled comparison of vaping cessation rates in those assigned to varenicline vs placebo.

Up to 300 adolescents, aged 16-25, who vape, do not smoke regularly, and want to quit vaping will be consented; approximately 225 eligible participants will be randomly assigned to a double blind, placebo-controlled intervention consisting of (1) varenicline or (2) identical placebo, up to 1 mg bid for 12 weeks, plus behavioral and texting support for adolescent vaping cessation or to (3) enhanced usual care. The primary comparison of interest is the double blind, placebo-controlled efficacy comparison of those assigned to (1) varenicline vs (2) placebo on vaping abstinence outcomes. The secondary comparison of placebo plus behavioral and texting support vs. EUC will estimate the efficacy of behavioral and texting support for vaping cessation in this population. The secondary comparison of varenicline plus behavioral and texting support vs EUC will estimate of the efficacy of varenicline treatment plus behavioral and texting support for vaping cessation in this population vs no treatment, the most common vaping cessation intervention. All participants will complete enrollment and baseline visits, and six monthly assessment visits. Those assigned to double blind intervention (study arms 1 or 2) will also complete 12 weekly behavioral support sessions. Assessors will be blind to intervention assignment (arm 1 or 2) vs EUC (arm 3) assignment. Among those assigned to the V+BC or P+BC intervention arms, study staff and participants will be blind to active varenicline vs placebo assignment, such that among those assigned to intervention (arm 1 or 2), assignment to study drug will be double blind. For those assigned a double blind intervention arm, study staff will distribute varenicline or identical appearing placebo and give instructions use at weeks 0, 2, 4 and 8. Participants will be asked to bring all empty and unused study medication at each in-person study visit through Week 12. The enrollment visit will consist of questionnaires, diagnostic assessments, vitals, saliva and urine samples. The baseline visit will consist of questionnaires, a saliva sample for cotinine concentration, and randomization. Monthly visits will consist of interviews, questionnaires and a saliva and urine sample. Weekly treatment meetings for participants assigned to arms 1 or 2 will consist of cognitive behavioral support and questionnaires.

Eligibility Criteria:
Inclusion Criteria:

* Ages 16-25, inclusive;
* Self-report of daily or near daily nicotine vaping for the prior ≥ 3 months and semi-quantitative saliva screening for cotinine positive for recent nicotine use;
* Nicotine dependence as defined by a score ≥4 on the 10-item E-cigarette Dependence Inventory (ECDI), or report of persistent use despite negative consequences, or prior failed quit attempts;
* Self-report of no regular combusted tobacco use in the past 2 months at enrollment and exhaled CO \<10 ppm;
* Total body weight at enrollment ≥35 kg (77 lbs);
* Report willingness to try varenicline to stop vaping;
* Able to understand study procedures and read and write in English;
* Have a parent or legal guardian who is able and willing to provide written informed consent (if under the age of 18);
* Competent and willing to provide written informed consent (if age 18+) or assent (if under 18);
* For participants who could become pregnant: negative urine pregnancy test at enrollment and agree to use effective contraception (e.g., abstinence, hormonal contraception, intra-uterine device, sterilization, or double barrier contraception) during the study.

Exclusion Criteria:

* Use of a smoking cessation medication in the prior month (nicotine patch, gum, nasal spray, or inhaler, varenicline, bupropion);
* Unwilling to abstain during the study from using smoking cessation aids other than those provided by the study;
* Unstable medical condition, epilepsy, severe renal impairment;
* Inpatient psychiatric hospitalization in the prior 6 months, serious suicidal ideation or suicide attempt within 6 months of enrollment, recent active suicidal ideation or suicidal behavior identified at enrollment or baseline visits;
* Evidence of active problem substance use severe enough to compromise ability to safely participate, in the investigator's opinion;
* Prior adverse drug reaction to varenicline;
* Unwilling to provide urine samples;
* Any condition or situation that would, in the investigator's opinion, make it unlikely that the participant could adhere safely to the study protocol;
* Ward of the state.