After an inspection unveiled the unclean conditions and failures in environmental monitoring for the positron emission tomography (PET) drug manufacturing site’s aseptic operation, the US Food and Drug Administration (FDA) sent a warning letter to Woburn, Massachusetts-based PETNET Solutions Inc.

The letter comprehended that the FDA inspector “observed a state of disrepair and lack of cleanliness” at the site, while “spore-forming fungi were repeatedly identified in the ISO 8 area.” The FDA further commented in the letter making remarks about the vigilant environmental control for the PET drug manufacturing and appropriate attention to microbial recovery in ISO 5 areas.