Assessing the real-world impact of a low nicotine product standard for smoked tobacco in New Zealand - ABSTRACT A low nicotine product standard for cigarettes and other combusted tobacco products has been proposed as a cornerstone of the FDA’s Comprehensive Plan for Tobacco and Nicotine Regulation in the United States (US). This proposed standard is based largely on randomized clinical trials demonstrating that when people switch to very low nicotine content (VLNC) cigarettes, cigarettes per day, dependence and biomarkers of smoke exposure decrease and quit attempts and cessation increase. Yet, these trials have impo rtant limitations. Notably, they limit the duration of exposure to VLNC cigarettes; cannot recreate the complex context of real - world product standards; are characterized by the use of non-study, normal nicotine cigarettes; and generally focus on samples of convenience. In December 2021, the New Zealand (NZ) Government launched the Smokefree Aotearoa 2025 Action Plan, outlining a strategy to reduce smoking prevalence to less than 5%. The plan is world-leading with transformative goals including: 1) eliminate health inequities in smoking rates and smoking-related illness; 2) ensure youth never start smoking tobacco; and 3) increase quitting in people who smoke. A major component of the initiative is to mandate a low nicotine product standard for all smoked tobacco. Our primary research objective is to assess the real-world impact of a mandated reduction of nicotine in all smoked tobacco products in NZ to inform the implementation of US nicotine reduction policy. We propose to conduct a longitudinal, mixed methods cohort study of adults who smoke daily or nearly daily (N=1500), using online surveys, biomarkers of exposure, physiological assessments, qualitative interviews, and medical records to assess changes in smoking behavior, health and well-being. We will follow the cohort for 3.5 years (1.5 years before and 1 year after implementation of a low nicotine product standard). We will also explore potential heterogeneity by explicitly sampling individuals from three priority populations important in NZ and the US (individuals with self-reported anxiety and depression; young adults living in socioeconomically deprived areas; and individuals who report heavy alcohol and/or cannabis use) and ensuring representation of NZ ethnic groups (Māori, Pacifika) with disproportionately high smoking prevalence. We will also enroll people who smoke but do not belong to priority populations. The primary outcome for Aim 1 is abstinence from smoked tobacco (self-reported and biochemically-verified) at 52 weeks after policy implementation. The primary outcome for Aim 2 is Health-Related Quality of Life ratings at 52 weeks after policy implementation. Aim 3 will explore potential heterogeneity in response to a low nicotine products standard. Our proposal will directly inform the US nicotine reduction policy agenda recently announced by the Biden Administration and aligns with several priorities outlined in RFA-OD-21-002. As a team, we have complementary areas of expertise (e.g., behavioral pharmacology, public health and medicine, biostatistics, epidemiology, qualitative and mixed methods, and health equity) to ensure the successful completion of the current proposal.