Over-the-Counter Drugs: Regulatory Analysis of Warning Letters Between Fiscal Years 2015-2019
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Helen K Bai1, Jennifer D Ahearn2, Michael G Bartlett3
1Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, GA, 30602, USA.
Background:
According to 21 Code of Federal Regulation (CFR) Part 211, Over-the-Counter (OTC) drug manufacturers must establish and follow current good manufacturing practices (cGMP) to produce quality products while meeting regulatory standards. The warning letters issued by the U.S. Food and Drug Administration (FDA) reveal quality inadequacies that may impact the safety and effectiveness of these products. This study provides an analysis of warning letters and cited violations to identify the most common areas of quality issues and to understand the FDA's current thinking on regulatory expectations.
Methods:
Warning letters between U.S. fiscal years (FY) 2015-2019 were analyzed by the following steps: extraction of CFR violations, categorization of violations, trend analysis of data, and interpretation of results.
Results:
A total of 116 OTC warning letters and for comparison purposes 561 prescription (Rx) warning letters were analyzed in this study. OTC drug violations relating to product and process controls significantly increased, while violations relating to labeling decreased over the years. Despite these changes in violation numbers, the number of violations increased in most categories, highlighting a continual increase of quality inadequacies.
Conclusion:
The quality issues are mostly seen in cGMP violations specifically in the drug product, process, and laboratory controls. Most significant violation changes are also seen in drug product and process controls. The overall number of violations in OTC drugs has been increasing in the past 5 years and the analysis results provide a projection for continued increases in violations. Although this study provides an overall quality analysis of OTC warning letters and cited violations, more studies are required to understand the risk to consumers using OTC drug products due to the trends associated with these observations.
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