Abstract: Objective Study the common problems of drug bacterial endotoxin control in FDA warning letters to provide reference for the industry. Methods The warning letters of the deficiencies in bacterial endotoxin control of FDA in recent years were sorted out, and the deficiencies in bacterial endotoxin control were classified and summarized. Results It is very critical to control bacterial endotoxin contamination in drug production. Although the relevant regulations and guidelines of FDA put forward clear requirements, there were still shortcomings in the actual implementation of active pharmaceutical ingredients/excipient /packaging materials,process control and quality control. Conclusion Bacterial endotoxin control is the key and difficult point of drug quality control. Enterprises should focus on and continuously optimize to ensure the safety and effectiveness of drugs.

Key words: bacterial endotoxin, warning letter, good manufacturing practice for drugs, quality control, deviation investigation, active pharmaceutical ingredients, excipient, FDA