The U.S. Food and Drug Administration approved Zycubo (copper histidinate, CUTX‑101) as the first therapy for Menkes disease, a lethal pediatric copper‑absorption disorder. Sentynl Therapeutics, which took over development from Cyprium, will commercialize the drug in the U.S. Approval came ahead of the PDUFA date after the sponsor addressed prior manufacturing issues. The clearance generated a rare pediatric disease priority review voucher (PRV) that will be transferred to Cyprium under the development agreement; the filing also defines potential tiered milestones and royalties. The decision gives clinicians an approved therapeutic option for an otherwise fatal pediatric condition and provides the sponsor with a commercial foothold in rare pediatric neurology while unlocking a PRV that has material economic value for developers of orphan drugs.