FDA Warning Letter over Serious Deficiencies in Sterile Manufacturing leads to a Production Shutdown

The U.S. Food and Drug Administration (FDA) issued a Warning Letter to K.C. Pharmaceuticals, Inc. on August 12, 2026, citing significant violations of Current Good Manufacturing Practice (CGMP) requirements. The action follows an inspection of the company’s facility in Pomona, California, conducted from January 20 to February 13, 2026. According to the FDA, the company’s methods, facilities and controls do not meet the requirements for the manufacture and testing of drugs.

Failed Media Fills

The most serious findings concern the manufacture of sterile drug products by aseptic processing. The company continued to manufacture and release sterile products after media fill failures recorded in June, September and November 2024. The associated investigations were, in the FDA’s assessment, neither timely nor sufficiently robust. Some proposed root causes were unsupported, and the corrective actions did not adequately address the underlying problems. This raised significant concerns about the reliability of the company’s sterility assurance and the acceptability of batches manufactured during the affected period.

Contamination Risks

The agency also observed poor practices in ISO 5 areas. Operators reportedly inserted their upper bodies into a Restricted Access Barrier System (RABS), breached the barrier during interventions and, in some cases, performed interventions without the specified tools. Such behavior can compromise the protection of the critical zone and increase the risk of microbial contamination. The FDA further concluded that the equipment and process design did not sufficiently minimize manual interventions or the contamination hazards associated with them.

Deficits in Smoke Studies

Additional concerns involved the facility’s Airflow Visualization Studies, commonly known as smoke studies. The studies did not consistently demonstrate unidirectional airflow or adequately show the impact of dynamic operator interventions. In some cases, camera placement, smoke-source positioning or the assessment of critical interventions was inadequate. The worst-case locations for environmental monitoring in the ISO 5 filling room and RABS had also not been sufficiently established through risk assessment. The FDA criticized K.C. Pharmaceuticals for failing to adequately evaluate the potential impact of these deficiencies on sterile products already distributed in the U.S. market.

Further deficiencies

The Warning Letter also identifies weaknesses in 100% visual inspection for particulate and visible defects, stability-indicating methods, laboratory system suitability testing, alarm investigations, complaint handling and Quality Unit oversight. The FDA requires a retrospective review of previous media fills and complaints, a comprehensive contamination-hazard risk assessment, robust corrective and preventive actions, and independent assessments of the laboratory and stability systems.

K.C. Pharmaceuticals has committed to shutting down production of the affected drug products. On February 18, 2026, the company also initiated a voluntary recall covering all commercial drug products manufactured between March 27 and November 7, 2024. Before operations resume, the FDA expects the company to complete extensive remediation. Read the full Warning Letter on the official FDA website.