# Nicotine Intervention and Communication for Empowering Reduction (NICER): study protocol for a randomized controlled trial among priority populations of people who smoke

## TL;DR

This study tests if adding messages about low-nicotine cigarettes helps people smoke less, focusing on those with low income or mental health issues.

## Contribution

This is the first trial to evaluate messaging alongside low-nicotine cigarettes in priority populations.

## Key findings

- Messages may reduce cigarettes smoked per day compared to low-nicotine cigarettes alone.
- Results could guide FDA policies on nicotine reduction and public health messaging.

## Abstract

Smoking is a leading cause of preventable death, disproportionately affecting people with low socioeconomic status (SES) and serious psychological distress (SPD). The U.S. Food and Drug Administration (FDA) has proposed reducing nicotine levels in cigarettes and other combusted tobacco products to minimally addictive levels, a policy with significant public health potential. However, misperceptions about very low nicotine cigarettes (VLNCs), such as beliefs that they are less harmful or ineffective for quitting, may reduce policy effectiveness. While previous randomized controlled trials (RCTs) have examined the effects of using VLNCs, none have incorporated messaging to address misperceptions. This study evaluates the impact of a messaging campaign on smoking behaviors, risk perceptions, and quit intentions among people who smoke, focusing on individuals with low SES, SPD, and neither. The primary objective is to assess whether exposure to VLNC-related messages reduces the number of cigarettes smoked per day compared to VLNC use alone. Secondary objectives include examining effects on other tobacco product use, nicotine dependence, forgoing cigarettes, perceived risks, and quit intentions.

This multi-site, open-label, parallel-arm RCT will enroll 1230 adults who smoke (n = 410 per group: with SPD, low SES, neither category). After a 1-week baseline period, participants will be randomized (1:1) to receive either (1) VLNCs with messaging or (2) VLNCs only (control). Messaging will include pack inserts and digital ads shown during weekly visits to address misperceptions and encourage quitting. Participants will complete daily logs via text messages and attend weekly visits over 4 weeks for data collection, including self-reported smoking behavior, expired carbon monoxide (CO) samples, and questionnaire assessments. The primary outcome is the number of cigarettes smoked per day in the final study week (week 4). Secondary outcomes include the use of other tobacco products, nicotine dependence, forgoing cigarettes, and quit intentions.

This trial will be the first to examine the effects of a messaging campaign accompanying VLNC use among priority populations. Results will inform FDA regulatory strategies and public health messaging to support nicotine reduction policy implementation.

ClinicalTrials.gov NCT06787937. Registered on 22 January 2025.