Sentynl Therapeutics' Menkes disease drug CUTX-101 nears FDA approval

Sentynl Therapeutics, a U.S.-based biopharmaceutical company wholly-owned by Zydus Lifesciences, announced on December 15, 2025, that the FDA accepted the resubmission of its new drug application (NDA) for copper histidinate (CUTX-101). This investigational drug is intended to treat Menkes disease in pediatric patients. The resubmission was classified as a Class I response, setting the new PDUFA target action date for January 14, 2026.

Sentynl originally resubmitted its revised NDA on November 14, 2025, following a complete response letter from the FDA on September 30, 2025. The prior CRL cited observations regarding the manufacturing site's cGMP compliance but did not identify concerns with CUTX-101's efficacy or safety data, which demonstrated improved overall survival for Menkes disease subjects receiving early treatment.

If approved, CUTX-101 would be the first and only FDA-approved treatment for Menkes disease, a rare X-linked recessive pediatric genetic condition affecting an estimated 1 in 34,810 to 1 in 8,664 live male births. The drug has already received FDA breakthrough therapy, fast track, rare pediatric disease, and orphan drug designations.