Ultragenyx Pharmaceutical entered into a definitive agreement to sell a Rare Pediatric Disease Priority Review Voucher for $210 million.

Ultragenyx received the voucher upon FDA’s approval of Genglycos (pariglasgene brecaparvovec-opnr), also known as Dtx401, the first treatment designed to address the underlying cause of glycogen storage disease type Ia.¹

The sale is expected to provide Ultragenyx with a fresh infusion of non-dilutive capital at a moment where the company is working to advance a pipeline of first-ever therapies for rare and ultra-rare diseases while also moving toward profitability.¹ It also illustrates a pattern the company has now repeated: the voucher earned through Genglycos’s approval is itself being monetized to fund future development, continuing a cycle that began when Genglycos’s own progress was supported by capital from an earlier voucher sale.¹

What is a Rare Pediatric Disease Priority Review Voucher?

The voucher program is a U.S. FDA initiative intended to encourage the development of new drug and biological products for the prevention and treatment of certain rare pediatric diseases.² Under the program, a sponsor that receives approval for a drug or biologic treating a qualifying rare pediatric disease may earn a voucher that can later be redeemed to secure priority review of a different, subsequent marketing application.

The sponsor receives the voucher at the time its rare pediatric disease product is approved, and the voucher itself can then be sold or transferred to another company.² That transferability is what allows a company like Ultragenyx to convert regulatory approval of one rare disease therapy directly into capital that can support work on others.

As of February 2026, the program is expected to sunset after September 30, 2029.²

What is Genglycos, and why did it qualify?

Genglycos, known generically as pariglasgene brecaparvovec-opnr and previously referred to by the development name Dtx401, is the first treatment designed to address the underlying cause of glycogen storage disease type Ia rather than simply managing its symptoms.¹ Its approval by FDA is what generated the voucher now being sold, and the therapy’s qualification under the Rare Pediatric Disease Priority Review Voucher program reflects the program’s core purpose: rewarding developers that bring forward treatments for rare conditions affecting children by granting them an asset that carries real market value beyond the approval itself.¹

"For patients waiting on new therapies, the acceptance of RWD can meaningfully shorten the time between scientific discovery and treatment availability.,” Dr. Patricia Greenstein, a neurologist and geneticist at Beth Israel Deaconess Medical Center told Pharmaceutical Executive.

What are the terms of the sale?

Under the definitive agreement, Ultragenyx will sell the voucher for $210 million. The closing of the transaction is subject to customary closing conditions, including expiration of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act. Jefferies LLC is serving as exclusive financial advisor to Ultragenyx on the transaction, while Gibson, Dunn and Crutcher LLP is serving as legal counsel.¹

“Monetizing this PRV provides significant non-dilutive capital to advance our efforts to bring forward first-ever therapies for rare and ultra-rare diseases, and supports our path to profitability,” said Howard Horn, chief financial officer and executive vice president, corporate strategy. “Genglycos itself benefited from capital generated from a previous PRV sale, demonstrating the important role the PRV program plays in helping companies develop transformative therapies for rare disease patients.”

Sources

1. Ultragenyx Enters into Agreement to Sell Rare Pediatric Disease Priority Review Voucher for $210 Million Ultragenyx October 7, 2026, https://www.globenewswire.com/news-release/2026/10/07/3376457/20739/en/ultragenyx-enters-into-agreement-to-sell-rare-pediatric-disease-priority-review-voucher-for-210-million.html
2. Rare Pediatric Disease Designation and Priority Review Voucher Programs U.S. FDA April 29, 2026, https://www.fda.gov/industry/medical-products-rare-diseases-and-conditions/rare-pediatric-disease-designation-and-priority-review-voucher-programs