Varenicline Smoking Cessation Treatment for Methadone Maintenance Patients

This randomized trial will evaluate whether varenicline directly observed therapy provided at a methadone clinic is more efficacious than self-administered varenicline for promoting smoking cessation and enhancing adherence.

There is a marked prevalence of tobacco use and tobacco-related disease among methadone maintenance patients. Varenicline's demonstrated efficacy may not be generalizable to methadone maintained smokers because of poor adherence, which is highly prevalent among drug users. Adherence to smoking cessation medication is strongly associated with cessation, and is one of the few factors shown to increase cessation among methadone maintained smokers, but strategies to promote smoking cessation medication adherence have not been evaluated in methadone patients. Based on the Information, Motivation, and Behavior model, the investigators plan a directly observed therapy (DOT)-based intervention targeting behavioral skills necessary for optimal adherence. Because methadone clinic-based DOT interventions have been shown to improve medication adherence and clinical outcomes in HIV and TB, the investigators plan to determine in a randomized trial whether DOT varenicline provided at a methadone clinic is more efficacious than self-administered varenicline for promoting smoking cessation and enhancing adherence. The investigators will also evaluate moderating effects of drug and alcohol use and psychiatric symptoms on DOT effects. The investigators hypothesize subjects in the mDOT arm will have greater 7 day point prevalence abstinence at 12 weeks, reduction in cigarettes/day, time to first daily cigarette, ≥ 24 hour quit attempts, and 7 day point prevalence abstinence at 24 weeks compared to subjects receiving self administered varenicline. The investigators also hypothesize that adherence in the mDOT arm will be higher than in the TAU arm. Lastly the investigators hypothesize that ongoing illicit drug use and psychiatric symptoms will moderate the effect of mDOT on adherence.

Subjects in the directly observed therapy (DOT) arm will receive varenicline directly administered by methadone clinic nurses 4-6 times per week at the same time as they receive methadone, as well as individually packaged take-home doses for self administration on evenings/weekends.

Varenicline, titrated to 1 mg twice daily, will be given to participants in both study arms for 12 weeks.

Pill count adherence, measured as pills taken divided by pills dispensed, analyzed as a continuous measure

Number of participants achieving self reported, seven day point prevalence abstinence, biochemically verified with expired carbon monoxide (CO) < 8 p.p.m., missing = smoking

Number of participants achieving self reported, seven day point prevalence abstinence, biochemically verified with expired carbon monoxide (CO) < 8 p.p.m.

Inclusion Criteria: Age 18 years or older English speaking Smoked at least 100 cigarettes/lifetime Smoke 5 or more cigarettes per day Interested in quitting smoking (preparation or contemplation stage of change) Enrolled in Einstein/Montefiore methadone program for 12 weeks or more Receiving methadone in clinic three, four, five or six times per week No more than 2 methadone clinic misses in prior 14 days Agree to use contraception for the duration of the trial (among women with reproductive potential) Willing to participate in all study components Able to provide informed consent Exclusion Criteria: Serious or unstable HIV/AIDS, liver, cardiovascular, or pulmonary disease Psychiatric instability Women who are pregnant, breastfeeding, or contemplating pregnancy Creatinine clearance <30 mL/min

Nahvi S, Adams TR, Ning Y, Zhang C, Arnsten JH. Effect of varenicline directly observed therapy versus varenicline self-administered therapy on varenicline adherence and smoking cessation in methadone-maintained smokers: a randomized controlled trial. Addiction. 2021 Apr;116(4):902-913. doi: 10.1111/add.15240. Epub 2020 Oct 13.

Nahvi S, Segal KS, Litwin AH, Arnsten JH. Rationale and design of a randomized controlled trial of varenicline directly observed therapy delivered in methadone clinics. Addict Sci Clin Pract. 2014 Jun 13;9(1):9. doi: 10.1186/1940-0640-9-9.