FDA Warning Letter: Missing Identity Tests, Unverified CoAs, and Inadequate DEG/EG Controls

On 12 August 2025, the U.S. Food and Drug Administration (FDA) published a Warning Letter dated 09 July 2025 issued to a U.S.-based manufacturer of over-the-counter (OTC) drug products. During an inspection in February 2025, the investigator observed several specific CGMP violations.

According to the FDA, the firm

• failed to establish an adequate Quality Unit (QU) with the responsibilities and authority to oversee the manufacturing of drug products,
• failed to test incoming components used in manufacturing finished OTC drug products to determine identity, purity, strength, and quality,
• failed to establish a vendor qualification program for raw material suppliers.

In particular, the company did not perform at least one specific identity test for each incoming lot and relied on supplier CoAs without establishing their reliability through initial validation and periodic re-validation. Given repeated global poisoning incidents linked to diethylene glycol (DEG) and ethylene glycol (EG), the FDA mandates risk-based controls for high-risk excipients (e.g., glycerin, propylene glycol).

The firm decided to cease production of all OTC drugs at this facility. Nevertheless, the Warning Letter was issued, as the authority has not received a response from the firm stating the actions it is taking to address the deficiencies identified during the inspection and cited on the Form FDA 483 that preceded the Warning Letter.

The full Warning Letter to Gussyup LLC dba Private Label Grooming is published on the FDA website.