Fortress Biotech and Cyprium Therapeutics Announce an Update on the NDA for CUTX-101
Fortress Biotech (Nasdaq: FBIO) and its subsidiary Cyprium Therapeutics announced that the FDA has issued a Complete Response Letter (CRL) for CUTX-101, their drug candidate for treating Menkes disease in pediatric patients. The CRL cited cGMP deficiencies at the manufacturing facility but did not raise concerns about the drug's efficacy or safety data.
Sentynl Therapeutics, which assumed development and commercialization responsibilities in December 2023, plans to address the FDA's concerns and pursue resubmission. Upon approval, Cyprium remains eligible for a Rare Pediatric Disease Priority Review Voucher and could receive up to $129 million in development and sales milestones, plus royalties from Sentynl.
Fortress Biotech (Nasdaq: FBIO) e la sua controllata Cyprium Therapeutics hanno annunciato che la FDA ha emesso una Lettera di Risposta Completa (CRL) per CUTX-101, candidato terapeutico per trattare la malattia di Menkes nei pazienti pediatrici. La CRL ha citato carenze cGMP presso l'impianto di produzione, ma non ha sollevato preoccupazioni sull'efficacia o sui dati di sicurezza del farmaco.
Sentynl Therapeutics, che ha assunto le responsabilità di sviluppo e commercializzazione nel dicembre 2023, intende affrontare le questioni dell'FDA e procedere alla presentazione ripetuta. Qualora approvata, Cyprium resta idonea per un Voucher di Revisione Prioritaria per Malattie Pediatriche Rare e potrebbe ricevere fino a 129 milioni di dollari in milestone di sviluppo e vendita, oltre a royalties da Sentynl.
Fortress Biotech (Nasdaq: FBIO) y su filial Cyprium Therapeutics anunciaron que la FDA ha emitido una Carta de Respuesta Completa (CRL) para CUTX-101, su candidato a fármaco para tratar la enfermedad de Menkes en pacientes pediátricos. La CRL citó deficiencias cGMP en la instalación de fabricación, pero no planteó preocupaciones sobre la eficacia o la seguridad de los datos del fármaco.
Sentynl Therapeutics, que asumió las responsabilidades de desarrollo y comercialización en diciembre de 2023, planea abordar las preocupaciones de la FDA y presentar una nueva solicitud. Una vez aprobada, Cyprium seguirá siendo elegible para un Voucher de Revisión Prioritaria para Enfermedades Pediátricas Raras y podría recibir hasta $129 millones en hitos de desarrollo y ventas, además de regalías de Sentynl.
Fortress Biotech (나스닥: FBIO) 및 자회사 Cyprium Therapeutics는 FDA가 CUTX-101에 대해 완전 응답 서한(CRL)을 발행했다고 발표했습니다. 이는 소아 환자의 메인케스병 치료를 위한 약물 후보에 대한 것입니다. CRL은 제조 시설의 cGMP 결함을 지적했지만 약물의 효능이나 안전성 데이터에 대한 우려는 제기하지 않았습니다.
2023년 12월 개발 및 상용화 책임을 인수한 Sentynl Therapeutics는 FDA의 우려를 해결하고 재제출을 추진할 계획입니다. 승인될 경우 Cyprium은 희귀 소아 질환 우선 검토 바우처를 받을 수 있는 자격을 유지하며, 개발 및 매출 이정표로 최대 1억2900만 달러를 받을 수 있고 Sentynl로부터 로열티도 받을 수 있습니다.
Fortress Biotech (NASDAQ : FBIO) et sa filiale Cyprium Therapeutics ont annoncé que la FDA a délivré une Lettre de Réponse Complète (CRL) pour CUTX-101, leur candidat médicament destiné au traitement de la maladie de Menkès chez les patients pédiatriques. La CRL a évoqué des carences cGMP dans l’installation de fabrication, mais n’a pas exprimé d’inquiétudes concernant l’efficacité ou la sécurité des données du médicament.
Sentynl Therapeutics, qui a assumé les responsabilités de développement et de commercialisation en décembre 2023, prévoit de résoudre les préoccupations de la FDA et de procéder à une nouvelle soumission. En cas d’approbation, Cyprium restera éligible à un Voucher de Révision Prioritaire pour Maladies Pédiatriques Rares et pourrait recevoir jusqu’à 129 millions de dollars en jalons de développement et de ventes, en plus des redevances de Sentynl.
Fortress Biotech (Nasdaq: FBIO) und seine Tochter Cyprium Therapeutics gaben bekannt, dass die FDA ein Complete Response Letter (CRL) für CUTX-101, ihren Wirkstoffkandidaten zur Behandlung der Menkes-Krankheit bei pädiatrischen Patienten, ausgestellt hat. Die CRL verwies auf cGMP-Mängel in der Herstellungsanlage, brachte jedoch keine Bedenken bezüglich Wirksamkeit oder Sicherheitsdaten des Arzneimittels vor.
Sentynl Therapeutics, das im Dezember 2023 die Entwicklungs- und Vermarktungsverantwortung übernommen hat, beabsichtigt, die Bedenken der FDA zu adressieren und eine erneute Einreichung vorzunehmen. Nach der Zulassung würde Cyprium weiterhin für einen Priority-Review-Voucher für seltene Kinderkrankheiten in Frage kommen und könnte bis zu 129 Millionen Dollar an Entwicklungs- und Verkaufsmeilensteinen sowie Lizenzgebühren von Sentynl erhalten.
فورتريس بايوتيك (ناسداك: FBIO) وشريكتها التابعة Cyprium Therapeutics قد أعلنت أن هيئة الغذاء والدواء الأمريكية (FDA) أصدرت رسالة استجابة كاملة (CRL) لدواء CUTX-101،候选 دواء لعلاج مرض مينكس لدى المرضى الأطفال. أشارت CRL إلى عيوب cGMP في منشأة التصنيع لكنها لم تذكر مخاوف تتعلق بفعالية الدواء أو سلامة البيانات.
تخطط Sentynl Therapeutics، التي تولت المسؤوليات التطويرية والتجارية في ديسمبر 2023، لمعالجة مخاوف FDA والمتابعة بإعادة التقديم. عند الموافقة، ستبقى Cyprium مؤهلة للحصول على قسيمة مراجعة أولوية للأمراض النادرة لدى الأطفال وقد تتلقى حتى 129 مليون دولار كمعالم تطوير ومبيعات، إضافة إلى العوائد من Sentynl.
Fortress Biotech（纳斯达克股票代码：FBIO）及其子公司 Cyprium Therapeutics 宣布，FDA 就 CUTX-101 发出了一份 完整答复函（CRL），用于治疗儿童患者的孟克斯病。CRL 指出制造设施存在 cGMP 方面的缺陷，但并未对药物的效力或安全性数据提出担忧。
自 2023 年 12 月接管开发与商业化工作的 Sentynl Therapeutics 计划解决 FDA 的关注点并推进重新提交。一旦获批，Cyprium 仍有资格获得 罕见儿童疾病优先审评券，并可能获得高达 1.29 亿美元 的开发与销售里程碑，以及来自 Sentynl 的特许使用费。
- None.
- FDA issued Complete Response Letter due to cGMP manufacturing deficiencies
- Drug approval delayed pending resolution of manufacturing issues
- Need for facility re-inspection and regulatory resubmission will extend timeline
Insights
FDA's CRL for CUTX-101 represents a temporary setback due to manufacturing issues, not efficacy or safety concerns, delaying potential revenue.
Fortress Biotech and Cyprium Therapeutics have encountered a regulatory hurdle in their pursuit of approval for CUTX-101, a treatment for pediatric Menkes disease. The FDA has issued a Complete Response Letter (CRL) citing cGMP (current Good Manufacturing Practice) deficiencies at the manufacturing facility – essentially identifying problems with production standards rather than with the drug itself.
This represents a temporary setback rather than a fundamental rejection. Critically, the FDA did not identify any concerns regarding the drug's efficacy or safety data, which indicates the clinical foundation of the application remains sound. The manufacturing facility has already provided responses to the FDA following a re-inspection in September 2025.
For context, Menkes disease is an extremely rare X-linked recessive disorder affecting copper metabolism that is typically fatal in early childhood. Having a viable treatment option would fulfill a significant unmet medical need, which explains why the application previously received Priority Review designation.
Sentynl Therapeutics, which assumed development responsibility in December 2023, will now need to address these manufacturing concerns before resubmission. While this creates a delay, the pathway to potential approval remains intact. Upon approval, Cyprium stands to receive substantial benefits: a Rare Pediatric Disease Priority Review Voucher (which can be worth
The presence of positive clinical efficacy results demonstrating improved survival rates suggests that once manufacturing issues are resolved, CUTX-101 may still have a promising path to market.
MIAMI, Oct. 01, 2025 (GLOBE NEWSWIRE) -- Fortress Biotech, Inc. (Nasdaq: FBIO) (“Fortress”) and its majority-owned subsidiary, Cyprium Therapeutics, Inc. (“Cyprium”), today announced that the U.S. Food and Drug Administration (“FDA”) has issued a Complete Response Letter (“CRL”) relating to the New Drug Application (“NDA”) for CUTX-101 (copper histidinate), intended to treat Menkes disease in pediatric patients.
In December 2023, Sentynl Therapeutics, Inc. (“Sentynl”), a U.S.-based biopharmaceutical company wholly-owned by Zydus Lifesciences, Ltd. (“Zydus Group”) assumed full responsibility for the development and commercialization of CUTX-101 from Cyprium. Cyprium expects its partner, Sentynl, will work expeditiously to address the FDA’s concerns and pursue resubmission promptly.
The CRL noted cGMP deficiencies had been observed at the facility where CUTX-101 is manufactured. The facility recently provided responses to the FDA’s September 2025 re-inspection of the facility, and Sentynl expects to request a meeting with the FDA to discuss the CRL and resubmission of the CUTX-101 NDA. The CRL did not cite any other approvability concerns, nor did it identify any deficiencies in CUTX-101’s efficacy and safety data.
Pursuant to the transaction with Sentynl, Sentynl will transfer to Cyprium, if issued upon approval, a Rare Pediatric Disease Priority Review Voucher (“PRV”), and Cyprium will also be eligible to receive royalties on net sales of CUTX-101 and up to
The CUTX-101 NDA was initially granted Priority Review by the FDA and is supported by positive topline clinical efficacy results for CUTX-101, demonstrating significant improvement in overall survival for Menkes disease subjects who received early treatment with CUTX-101.
About Menkes Disease
Menkes disease is a rare X-linked recessive pediatric disease caused by gene mutations of the copper transporter ATP7A. The minimum birth prevalence for Menkes disease is believed to be 1 in 34,810 live male births, and potentially as high as 1 in 8,664 live male births, based on recent genome-based ascertainment (Kaler SG, Ferreira CR, Yam LS. Estimated birth prevalence of Menkes disease and ATP7A-related disorders based on the Genome Aggregation Database (gnomAD). Molecular Genetics and Metabolism Reports 2020 June 5;24:100602). The condition is characterized by distinctive clinical features, including sparse and depigmented hair (“kinky hair”), connective tissue problems, and severe neurological symptoms such as seizures, hypotonia, failure to thrive, and neurodevelopmental delays. Mortality is high in untreated Menkes disease, with many patients dying between 2-3 years of age. Milder versions of ATP7A mutations are associated with other conditions, including Occipital Horn Syndrome and ATP7A-related Distal Motor Neuropathy. Currently, there is no FDA-approved treatment for Menkes disease and its variants.
About Cyprium Therapeutics
Cyprium Therapeutics, Inc. (“Cyprium”) is focused on the development of novel therapies for the treatment of Menkes disease and related copper metabolism disorders. In March 2017, Cyprium entered into a Cooperative Research and Development Agreement with the Eunice Kennedy Shriver National Institute of Child Health and Human Development (“NICHD”), part of the NIH, to advance the clinical development of CUTX-101 (Copper Histidinate injection) for the treatment of Menkes disease. CUTX-101 is an investigational drug currently under FDA review to treat patients with Menkes disease. In 2023, Cyprium completed the transfer of its proprietary rights and assigned its FDA documents pertaining to CUTX-101 to Sentynl Therapeutics, Inc. Cyprium and NICHD also have an ongoing worldwide, exclusive license agreement to develop and commercialize adeno-associated virus (AAV)-based gene therapy, called AAV-ATP7A, to deliver working copies of the copper transporter that is defective in patients with Menkes disease, and to be used in combination with CUTX-101; AAV-ATP7A gene therapy is currently in pre-clinical development and has received FDA Orphan Drug Designation. Cyprium was founded by, and is a majority-owned subsidiary of, Fortress Biotech, Inc. (Nasdaq: FBIO). For more information, visit www.cypriumtx.com.
About Fortress Biotech
Fortress Biotech, Inc. (“Fortress”) is an innovative biopharmaceutical company focused on acquiring and advancing assets to enhance long-term value for shareholders through product revenue, equity holdings and dividend and royalty income. The company has eight marketed prescription pharmaceutical products and multiple programs in development at Fortress, at its majority-owned and majority-controlled partners and subsidiaries and at partners and subsidiaries it founded and in which it holds significant minority ownership positions. Fortress’ portfolio is being commercialized and developed for various therapeutic areas including oncology, dermatology, and rare diseases. Fortress’ model is focused on leveraging its significant biopharmaceutical industry expertise and network to further expand and advance the company’s portfolio of product opportunities. Fortress has established partnerships with some of the world’s leading academic research institutions and biopharmaceutical companies to maximize each opportunity to its full potential, including AstraZeneca, City of Hope, Nationwide Children’s Hospital, Columbia University, Dana Farber Cancer Center and Sentynl Therapeutics. For more information, visit www.fortressbiotech.com.
Forward-Looking Statements
Statements in this press release that are not descriptions of historical facts are “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, as amended. The words “anticipates,” “believes,” “can,” “continue,” “could,” “estimates,” “expects,” “intends,” “may,” “might,” “plans,” “potential,” “predicts,” “should,” or “will” or the negative of these terms or other comparable terminology are generally intended to identify forward-looking statements. These forward-looking statements are based on management’s current expectations and are subject to risks and uncertainties that could negatively affect our business, operating results, financial condition and stock price. Factors that could cause actual results to differ materially from those currently anticipated include risks relating to: whether the CUTX-101 NDA is approved in a timely manner, or at all, and whether a PRV is granted in connection therewith; our growth strategy, financing and strategic agreements and relationships; our need for substantial additional funds and uncertainties relating to financings; uncertainty related to the timing and amounts expected to be realized from future milestone, contingent value right, royalty or similar future revenue streams, if at all; our ability to identify, acquire, close and integrate product candidates successfully and on a timely basis; our ability to attract, integrate and retain key personnel; the early stage of products under development; the results of research and development activities; uncertainties relating to preclinical and clinical testing; our ability to obtain regulatory approval for products under development; our ability to successfully commercialize products or other marketable assets for which we receive regulatory approval or receive royalties or other distributions from third parties; our ability to secure and maintain third-party manufacturing, marketing and distribution of our and our partner companies’ products and product candidates; government regulation; patent and intellectual property matters; competition; as well as other risks described in our SEC filings. We expressly disclaim any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in our expectations or any changes in events, conditions or circumstances on which any such statement is based, except as may be required by law, and we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. The information contained herein is intended to be reviewed in its totality, and any stipulations, conditions or provisos that apply to a given piece of information in one part of this press release should be read as applying mutatis mutandis to every other instance of such information appearing herein.
Company Contact:
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Fortress Biotech, Inc.
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ir@fortressbiotech.com
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