Very low nicotine content cigarettes for smoking cessation: Examining a facilitated extinction approach and dosing schedule.

Abstract

We evaluated a behavioral intervention (facilitated extinction versus standard cessation counseling) and Very Low Nicotine Content (VLNC) reduction schedule (immediate versus gradual) for smoking cessation in a 2 × 2 design over 5 weeks prior to target quit date (TQD). The facilitated extinction strategies included maintaining the smoking rate across multiple smoking contexts to maximize extinction processes. Treatment-seeking individuals who smoke cigarettes were randomized to one of four conditions. The initial target sample size was 208 to detect differences in abstinence two months post-treatment. Due to the study pause with the onset of the COVID-19 pandemic, we achieved a sample size of 127 (58 % female). Primary outcomes were treatment feasibility and in-treatment measures, including weekly self-reports of cigarettes per day (CPD), reinforcing effects of smoking, and cravings to smoke study cigarettes. Treatment satisfaction was assessed at TQD. Treatment completion at 80 % supports feasibility, with a higher rate for gradual reduction groups (88 % versus 72 %, p = .026). High adherence to VLNC cigarettes across 5 weeks also supports feasibility. Mixed models found reduced craving to smoke study cigarettes (p < .001), reduced satisfaction with smoking (p < .001), and a decrease in study CPD (p < .001), with a greater decrease in CPD in immediate reduction groups (p = .006). Biochemically verified 7-day point prevalence abstinence two months post-treatment was 29 % and 31 % with missing data imputed as smoking, with no group differences. Overall high treatment satisfaction (M=3.8 out of 4) supports acceptability. These findings suggest VLNC cigarettes may aid broadly in cessation efforts and demonstrate feasibility for larger trials.