Kellin Chemicals (Zhangjiagang) Co., Ltd. – FDA Warning Letter, Jul 11, 2025

Kellin Chemicals Co., Ltd. - Zhangjiagang, an active pharmaceutical ingredient supplier based in China, received a formal warning letter from the FDA on November 6, 2025, following its refusal to permit a preannounced regulatory inspection. The inspection was scheduled to occur from July 7 to July 11, 2025. According to the Federal Food, Drug, and Cosmetic Act, drugs manufactured at facilities that deny or limit access to inspectors are legally considered adulterated. This designation is critical because it prevents the FDA from confirming that the facility adheres to essential manufacturing quality standards. Due to this refusal, the FDA may withhold approval for any new drug applications or supplements that include the company as a supplier. Additionally, the agency warned that shipments from this facility may be detained or refused entry into the United States. The FDA recommended that Kellin Chemicals notify its U.S. customers of the situation, as receiving or distributing adulterated materials constitutes a violation of federal law. The company is required to provide a written response within 15 working days. This response must include a plan to address the violation, any relevant supporting information, or a formal request to schedule a new inspection. Until the FDA successfully inspects the facility and confirms compliance, the firm faces significant restrictions on its ability to supply the U.S. market.