The U.S. Food and Drug Administration approved Zycubo (copper histidinate, CUTX‑101) as the first treatment for Menkes disease, a fatal pediatric disorder of copper absorption. Sentynl Therapeutics, which took over development from Cyprium, secured the approval ahead of the PDUFA date following manufacturing remediation after a prior CRL. The approval generates a rare pediatric disease priority review voucher for the NDA sponsor per company disclosures.