FDA CRL - Sentynl Therapeutics, Inc.

The FDA issued a Complete Response Letter to Sentynl Therapeutics, Inc. regarding their New Drug Application (NDA 211241) for copper histidinate. The document, dated September 30, 2025, states that the application cannot be approved in its current form due to several critical issues. Primary concerns involve manufacturing facilities where recent inspections identified deficiencies in Current Good Manufacturing Practice (CGMP) standards. The FDA requires satisfactory resolution of these violations and may require follow-up pre-approval inspections before reconsidering the application. Additionally, the FDA identified significant deficiencies in the proposed prescribing information and carton labeling, requiring the company to correct formatting and content errors to meet regulatory standards. Sentynl must also provide a comprehensive safety update, incorporating all new data from clinical and nonclinical studies to reflect the drug’s current safety profile. Under the regulatory framework of 21 CFR 314.110, the company has one year to address all identified deficiencies in a single resubmission. Failure to respond within this timeframe may result in the application being considered withdrawn. The company is encouraged to meet with the FDA to clarify the necessary steps for approval.