BizCare Benefits and PrismHR Partner to Offer Affordable and Flexible ICHRA Plans

Fortress Biotech's shares plummeted 31% in premarket trading after the FDA declined to approve CUTX-101, a treatment for Menkes disease, a rare genetic disorder. The drug, developed by Fortress and its Indian partner Zydus Lifesciences, failed to meet the FDA's approval criteria. This setback is a significant blow to the company and its investors, and the stock's sharp decline reflects the disappointment.

Fortress Biotech, Inc. (Nasdaq: FBIO) experienced a significant setback on September 12, 2025, when its shares plummeted by 31% in premarket trading. The decline was sparked by the U.S. Food and Drug Administration's (FDA) decision to decline the approval of CUTX-101, an investigational drug developed by Fortress and its Indian partner Zydus Lifesciences, Ltd. for the treatment of Menkes disease, a rare genetic disorder.

Menkes disease is a severe pediatric condition characterized by neurological symptoms and early mortality, with no current FDA-approved treatments available. CUTX-101 was under review for its potential to treat Menkes disease, and the drug demonstrated positive topline clinical efficacy results, showing significant improvement in overall survival for treated subjects Fortress Biotech and Cyprium Therapeutics Receive Complete Response Letter from FDA for CUTX-101 NDA for Menkes Disease Treatment^[1].

However, the FDA issued a Complete Response Letter (CRL) for the New Drug Application (NDA) of CUTX-101, citing cGMP (current Good Manufacturing Practice) deficiencies at the manufacturing facility. The CRL did not raise concerns regarding the efficacy or safety data of CUTX-101, indicating that the primary issue was related to manufacturing compliance Fortress Biotech and Cyprium Therapeutics Receive Complete Response Letter from FDA for CUTX-101 NDA for Menkes Disease Treatment^[1].

Fortress Biotech's stock price decline reflects the disappointment among investors following this regulatory setback. The company's subsidiary, Cyprium Therapeutics, Inc., which developed CUTX-101, will be significantly impacted by this decision. Sentynl Therapeutics, Inc., a wholly-owned subsidiary of Zydus Lifesciences, Ltd., assumed full responsibility for the development and commercialization of CUTX-101 from Cyprium in December 2023 and will work to address the FDA's concerns and seek resubmission Fortress Biotech and Cyprium Therapeutics Receive Complete Response Letter from FDA for CUTX-101 NDA for Menkes Disease Treatment^[1].

The FDA's decision highlights the importance of stringent manufacturing standards in the approval process. Despite the setback, Fortress Biotech and its partners continue to invest in the development of novel therapies for rare diseases, aiming to address significant unmet medical needs.