FDA Warning Letter: Component Testing, Validation, and Stability

The U.S. Food and Drug Administration (FDA) issued a Warning Letter dated 06 September 2024 to Diamond Chemical Co., Inc. which was published on the FDA website on 01 October 2024. This letter goes back to an inspection at the company's drug manufacturing facility in New Jersey in May 2024.

The document summarizes significant violations of Current Good Manufacturing Practice (CGMP) regulations for finished pharmaceuticals, including the following:

• Failure to Test Components for Identity and Purity: The FDA noted that the firm did not test all incoming drug components to verify their identity and purity, including the active ingredient ethanol. The agency strongly advised the company to implement identity testing protocols for all components and to conduct thorough purity testing when receiving materials.
• Lack of Adequate Testing for Final Product: Diamond Chemical Co., Inc. failed to ensure that each batch of the final product met established specifications, including identity, strength, quality, and purity.
• Inadequate Process Validation: The company did not validate manufacturing processes. The firm stated that the ethanol content in the finished drug products was addressed through testing of water content, density measurements, hydrometer measurements, and third-party testing. From the FDA's point of view, this is inadequate, as testing alone does not demonstrate that the manufacturing process is validated.
• Inadequate Cleaning Validation: The firm lacked cleaning validation studies for non-dedicated equipment used in manufacturing drug and non-drug products, such as industrial dish and laundry detergents.
• Absence of a Stability Testing Program: Diamond Chemical Co., Inc. did not implement a stability testing program to determine the product’s shelf life, which is essential for verifying the safety and effectiveness of drugs over time.

The FDA strongly recommended that Diamond Chemical Co., Inc. engage CGMP experts to develop a compliant quality management system. The company is required to submit a written response within 15 working days, detailing specific steps taken to address these issues.