FDA 483 - Sato Pharmaceutical Co., Ltd. - November 21, 2025

Sato Pharmaceutical Co., Ltd., an OTC drug manufacturer based in Hachioji, Tokyo, Japan, underwent an FDA inspection from November 13 to November 21, 2025. The inspection revealed significant compliance issues, particularly concerning the firm's sterile drug manufacturing processes. The primary violation noted was the failure to thoroughly investigate and resolve discrepancies in media fill tests, which repeatedly identified contamination by Bacillus cereus and other microorganisms. Despite corrective actions, such as plumbing renovations on the aseptic line, the firm continued to experience media fill failures with both bacterial and foreign matter contamination.

Additionally, the FDA observed that Sato Pharmaceutical's procedures to prevent microbiological contamination were inadequate. Specifically, the firm's airflow visualization studies for the aseptic filling line did not adequately validate the aseptic process, as the smoke used in these studies failed to demonstrate uniform airflow, indicating potential turbulence that could compromise sterility.

The FDA requires Sato Pharmaceutical to conduct a comprehensive investigation to identify the root causes of these failures and implement effective corrective and preventive actions. The firm must also ensure that its aseptic processes are properly validated to prevent future contamination. These actions are necessary to comply with FDA regulations and ensure the safety and efficacy of products intended for the U.S. market.