FDA Warning Letter to Baxter: Sterile Manufacturing Failures

The U.S. Food and Drug Administration (FDA) has issued a Warning Letter to Baxter International Inc. after an inspection of its Round Lake drug manufacturing facility in Illinois. The agency cites serious violations of Current Good Manufacturing Practice (CGMP) and concludes that the company's drug products are adulterated. It also says that repeated failures at several company sites point to inadequate management oversight.

Cross-Contamination Between Cephalosporin and Non-Beta-Lactam Areas

The most serious finding concerns the inadequate separation of cephalosporin production from other injectable products. Here you will find more information about this topic.

Aseptic Processing and Sterilization

FDA identified serious weaknesses in the sterile manufacturing operation. The violations include:

• Biological Indicator (BI) recoveries and inadequate validation
• Inadequate aseptic process simulation
• Inadequate environmental monitoring (EM)
• Inadequate airflow

FDA concluded that the design of the aseptic operation poses excessive contamination risk and that the company has not committed to the infrastructure upgrades needed to fix it.

Visual Inspection and Particulate Matter

FDA found that the manual visual inspection program cannot reliably detect defects. Operators were not properly qualified, were not tested on the smallest visible particles, and inspected units too quickly, contrary to the standards the company's own procedures cite. Particulate complaints rose significantly between 2023 and 2025 indicated an inadequate visual inspection program.

Investigations and Sterility Testing

The letter also criticizes the company's investigation system. In the first case the container-closure leak rates rose every year from 2023 to 2026, yet the number of non-conformance reports fell. In a second case (cefazolin sterility failure in 2025), the company invalidated the result by reclassifying the test as a "no-test," even though its records showed that the container had initially been verified as integral. The lot was released in July 2025 without a Phase II investigation. FDA rejects the company's conclusion that laboratory error was the definitive root cause and notes that the company has not addressed why its records described the container as integral.

Required Response

FDA expects a comprehensive independent evaluation of the cephalosporin separation measures and a full risk assessment of beta-lactam contamination. It also requires a remediation plan for the aseptic operation, covering interim measures as well as long-term equipment and facility upgrades. The Quality Unit must be strengthened with independent authority over batch release. Baxter must also review all its facilities for similar problems and engage a consultant qualified under 21 CFR 211.34 to conduct a six-system audit.

You will find the complete Warning Letter on the FDA website.