FDA Approves First Treatment for Menkes Disease in Children

TUESDAY, Jan. 20, 2026 (HealthDay News) — The U.S. Food and Drug Administration has approved the Zycubo (copper histidinate) injection as the first treatment for Menkes disease in pediatric patients.  

The copper replacement therapy is given by subcutaneous injection. The most common side effects reported with Zycubo included infections, respiratory problems, seizures, vomiting, fever, anemia, and injection site reactions. The FDA said that because copper can accumulate in the body, patients receiving Zycubo should be closely monitored for potential toxicity.

The approval is based on results from two open-label, single-arm clinical trials that included 66 treated patients (ages 3 years and younger) and 17 untreated patients. Results showed children who began treatment within four weeks of birth had a 78 percent reduction in the risk for death compared with that seen in untreated patients. Among early-treated patients, nearly half survived beyond six years, with some surviving more than 12 years. No untreated patients survived beyond six years. Substantial survival benefits were also seen in children who started treatment more than four weeks after birth.

“With today’s action, children with this devastating, degenerative disease will have an FDA-approved treatment option and the potential to live longer,” Christine Nguyen, M.D., of the FDA Center for Drug Evaluation and Research, said in a statement. “The FDA will continue to work with the rare disease community to advance drug development for patients with Menkes disease and other rare conditions.”

Approval of Zycubo was granted to Sentynl Therapeutics.

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