1 October 2025 - Sentynl Therapeutics announced today that the US FDA has issued a complete response letter relating to its new drug application for copper histidinate (CUTX-101), intended to treat Menkes disease in paediatric patients.

The FDA provided findings within the CRL that Sentynl and Zydus will need to address to clarify the path forward. Specifically, the FDA mentioned a CGMP inspection of the facility where CUTX-101 is manufactured. Zydus recently provided responses to FDA's September 2025 re-inspection demonstrating the facility's CGMP compliance and is awaiting USFDA's Establishment Inspection Report.

Read Sentynl Therapeutics press release