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Accepted for/Published in: JMIR Public Health and Surveillance

Date Submitted: Aug 5, 2025
Date Accepted: Dec 10, 2025

The final, peer-reviewed published version of this preprint can be found here:

The Impact of US Food and Drug Administration’s Advisory and Enforcement Actions on US Sales of Esco Bars Products in 2023: Synthetic Control Approach

Shin H, Hannings J, Cahn Z, Xu X, Toblin R, Farrelly M, King BA

The Impact of US Food and Drug Administration’s Advisory and Enforcement Actions on US Sales of Esco Bars Products in 2023: Synthetic Control Approach

JMIR Public Health Surveill 2026;12:e81033

DOI: 10.2196/81033

PMID: 41818484

The Impact of FDA Advisory and Enforcement Actions on US Sales of Esco Bars Products in 2023: Synthetic Control Method

  • Hyungsik Shin; 
  • Jonathan Hannings; 
  • Zachary Cahn; 
  • Xin Xu; 
  • Robin Toblin; 
  • Matthew Farrelly; 
  • Brian A. King

ABSTRACT

Background:

In 2023, Esco Bars was the second most commonly reported e-cigarette brand used among U.S. middle and high school student e-cigarette users. These products have not been authorized for sale in the United States by the U.S. Food and Drug Administration (FDA). On May 12 and May 25, 2023, FDA issued an import alert and a warning letter, respectively, to the manufacturer requiring them to immediately remove these unauthorized products from the market. On June 22 and July 27, 2023, FDA also issued warning letters to U.S. retailers and distributors, respectively, regarding the illicit sale of these unauthorized products. This study evaluated the impact of these advisory and enforcement actions on retail sales of Esco Bars in the United States.

Objective:

We evaluated the impact of these 2023 FDA advisory and enforcement actions on illicit sales of unauthorized Esco Bars to better inform future regulatory decision-making.

Methods:

This study used a synthetic control method to evaluate the impact of 2023 FDA advisory and enforcement actions on Esco Bars sales based on weekly sales data from NielsenIQ Retail Measurement Service between January 1 and December 30, 2023. Data came from the 48 contiguous states; data were not available for Internet and vape shop sales. First, we standardized the data by transforming weekly sales into Z-scores. Second, we created a synthetic comparison for Esco Bars sales based on sales of other e-cigarettes for which FDA did not take actions during the analytical period. Finally, we calculated the difference in sales between Esco Bars and the comparison group before and after the FDA actions. To assess the robustness of the findings, we used other standardization methods for sensitivity analyses.

Results:

By the last week of 2023, actual Esco Bars weekly sales were 68.5% lower than estimated sales in the comparison group (p=0.019). Over the 5-month period following FDA advisory and enforcement actions, Esco Bars product sales were reduced by approximately 1.7 million equivalized units (p=0.058). These findings were robust across sensitivity analyses.

Conclusions:

FDA’s advisory and enforcement actions substantially reduced sales of Esco Bars products in the U.S., with a sustained impact noted over a 5 month period. These findings underscore the importance and impact of FDA actions against unauthorized tobacco products as part of a comprehensive regulatory approach.


 Citation

Please cite as:

Shin H, Hannings J, Cahn Z, Xu X, Toblin R, Farrelly M, King BA

The Impact of US Food and Drug Administration’s Advisory and Enforcement Actions on US Sales of Esco Bars Products in 2023: Synthetic Control Approach

JMIR Public Health Surveill 2026;12:e81033

DOI: 10.2196/81033

PMID: 41818484

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