FDA Warning Letter: Inadequate Testing of BZK and Many General GMP Violations
Recommendation

Thursday, 3 September 2026 9 .00 - 17.00 h
Establishment, Use and Maintenance of Analytical Reference Substances
The U.S. Food and Drug Administration (FDA) has published a Warning Letter dated 08 November 2023. Beside a whole series of general GMP violations, the authority in particular blames the company for failing to test the incoming component benzalkonium chloride (BZK).
The company manufactures over-the-counter (OTC) topical drug products, such as antibacterial hand sanitizers containing BZK. During an inspection of the drug manufacturing facility in May 2023, significant violations of Current Good Manufacturing Practice (CGMP) regulations were found. These include:
- The company was unable to provide documentation of the component testing of BZK, including identity.
- The supplier qualification program was inadequate.
- An adequate ongoing stability program was not established.
- Adequate procedures describing out-of-specifications, deviations, manufacturing equipment cleaning, process validation, and pest control were missing.
- Appropriate validation and approved written procedures for cleaning and maintenance of non-dedicated manufacturing equipment could not be provided.
The FDA writes that the company's inspection history indicates that the quality unit (QU) is not able to fully exercise its authority and/or responsibilities, as a previous inspection in November 2021 showed similar CGMP observations.
Apparently, the company has realized in the meantime that CGMP Compliance is not possible under these conditions and has committed to cease production of all drugs at the facility.
For further information, please see the complete Warning Letter to National Chemical Laboratories at the FDA website.
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