Fortress Biotech, Inc. (NASDAQ:FBIO) said its majority-owned subsidiary Cyprium Therapeutics has signed a definitive agreement to sell a Rare Pediatric Disease Priority Review Voucher (PRV) for gross proceeds of $205 million, marking a significant monetization event following the recent FDA approval of ZYCUBO®.
The voucher was granted after the U.S. Food and Drug Administration approved ZYCUBO® (copper histidinate), formerly known as CUTX-101, on January 12, 2026 for the treatment of Menkes disease. Under a prior agreement reached in December 2023, Sentynl Therapeutics assumed full responsibility for development and commercialization of the therapy. The PRV was subsequently transferred to Cyprium, enabling the company to pursue the sale.
In addition to proceeds from the transaction, Cyprium remains eligible to receive tiered royalties on global net sales of ZYCUBO as well as up to $129 million in potential development and sales milestone payments from Sentynl. The company is also required to allocate 20% of PRV sale proceeds to the Eunice Kennedy Shriver National Institute of Child Health and Human Development, part of the U.S. National Institutes of Health.
“The recent approval of ZYCUBO was a significant achievement for patients with Menkes disease and the sale of the PRV by Cyprium shows our continued execution in value-generating corporate transactions,” said Lindsay A. Rosenwald, M.D., Fortress’ Chairman, President and Chief Executive Officer and Cyprium’s Chairman. “With the PRV sale and three FDA approvals received in the last 15 months for Emrosi™, UNLOXCYT™, and ZYCUBO, in addition to the recent sale of our former subsidiary Checkpoint Therapeutics to Sun Pharma, we believe that we are well positioned to continue to execute on our portfolio. We look forward to the potential achievement of upcoming milestones across our extensive pipeline of commercial and clinical-stage assets.”
Cyprium leadership said the agreement builds on recent operational momentum following ZYCUBO’s approval.
“We are very pleased with the recent progress at Cyprium, which includes the approval of ZYCUBO for the treatment of Menkes disease along with the execution of this important agreement,” said Lung S. Yam, M.D., Ph.D., Cyprium’s President and Chief Executive Officer. “We are deeply grateful for everyone’s support and look forward to advancing AAV-ATP7A Gene Therapy toward clinical development to provide additional therapeutic options for patients with Menkes disease.”
The transaction remains subject to customary closing conditions, including expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act.
About Cyprium Therapeutics
Cyprium Therapeutics focuses on developing treatments for Menkes disease and related copper metabolism disorders. The company previously collaborated with the Eunice Kennedy Shriver National Institute of Child Health and Human Development under a Cooperative Research and Development Agreement to advance copper histidinate therapy. Following the transfer of rights to Sentynl Therapeutics in 2023, ZYCUBO received FDA approval in 2026 for pediatric Menkes disease patients. Cyprium is also advancing AAV-ATP7A, an adeno-associated virus gene therapy designed to deliver functional copper transporter genes, which is currently in preclinical development and holds FDA Orphan Drug Designation. Cyprium is a majority-owned subsidiary of Fortress Biotech.
About Fortress Biotech
Fortress Biotech is a biopharmaceutical company focused on acquiring, developing and commercializing therapeutic assets across oncology, dermatology and rare diseases. The company generates value through product revenue, equity ownership, royalties and partnerships, and currently supports eight marketed prescription products alongside multiple clinical and development programs across its subsidiaries and partner network. Fortress collaborates with leading academic and industry institutions including AstraZeneca, City of Hope, Fred Hutchinson Cancer Center, Nationwide Children’s Hospital, Columbia University, Dana-Farber Cancer Center and Sentynl Therapeutics.