More than $4 billion in potential reinvestment for rare disease drug development could be lost if the U.S. Congress does not reinstate the rare pediatric disease priority review voucher (PRV) program, according to a new report from the Rare Disease Company Coalition (RDCC). The program, which expired in December 2024, has played a key role in incentivizing biotech companies to develop treatments for conditions with limited options.
“That foregone value is very significant, particularly for small and emerging biotechs that operate on very tight margins and for patients who already have such limited treatment options,” said Stacey Frisk, executive director of RDCC. She noted that 95% of rare diseases currently lack targeted treatments.
The PRV program was launched in 2012 to encourage drug development for rare pediatric diseases affecting fewer than 200,000 people in the U.S. Under this initiative, sponsors could apply for an FDA designation; if their drug was approved, they would receive a voucher to expedite future FDA reviews. These vouchers could also be sold—sometimes fetching as much as $150 million before the program lapsed at the end of 2024. According to a BioSpace analysis, 2024 saw more PRVs awarded than any previous year since inception, with companies spending $513 million on vouchers earned that year.
RDCC’s analysis indicates about 200 therapies are now at risk of losing eligibility for a PRV unless Congress acts soon. Of these, an estimated 37 might still secure approval without a voucher attached. “What that translates into is an estimated $4 billion in lost reinvestment potential,” Frisk explained.
Legislation known as the Mikaela Naylon Give Kids a Chance Act of 2025 passed the House last week as part of a larger government funding bill and now awaits Senate consideration. Frisk referenced communication from Gary Andres, assistant secretary for legislation at the Department of Health and Human Services (HHS), who wrote: “HHS strongly supports reauthorization of the [rare pediatric disease] PRV program through September 30, 2029 as proposed in Section 5.”
Industry leaders have voiced concerns about worsening funding challenges amid increased competition from Chinese innovation and broader economic pressures. Bo Cumbo, CEO of Solid Biosciences—a company focused on genetic medicines for rare neuromuscular diseases—said: “The last five years for small startup companies, especially in the rare disease space, have been extremely challenging… and the removal or the end of the priority review voucher will be just sort of that final straw that breaks the back of the rare disease companies.”
A survey by RDCC found that 85% of biotech executives considered PRVs significant when deciding whether to pursue rare pediatric projects; since its lapse, over one-third have canceled or delayed programs while half anticipate further difficulties accessing capital.
“Right now, there’s a lack of predictability,” said Justin To, CEO overseeing skeletal dysplasia programs at BridgeBio. “Without knowing whether or not Congress is going to reauthorize the program… uncertainty really starts to kind of choke off investment in developing pediatric programs.”
Cumbo added: “If this rare disease voucher program is removed, you’re going to watch many of the smaller programs—[with] 10,000 or less patients—be cut.” He indicated only his company’s lead Duchenne muscular dystrophy therapy would likely survive under such constraints.
BridgeBio’s Nulibry became available thanks partly to support from PRVs after receiving FDA approval in February 2021 for treating molybdenum cofactor deficiency Type A. To stated: “The reason why we were able to get that therapy approved was because of the pediatric review voucher… The PRV certainly makes it possible for us to develop medicines for ultra-rare diseases like we did for MoCD.”
Dan Williams, CEO at SynaptixBio—which develops therapies for TUBB4a-related leukodystrophy—emphasized how important expedited regulatory pathways and funds from selling vouchers are: “It’s difficult enough to get investment into early-stage companies… but with rare diseases… you really need to try everything you can.” He said such mechanisms help reduce risks so investors can participate earlier.
Recent regulatory changes reflect momentum within this sector. In November 2025, the FDA introduced an approval pathway based on plausible mechanisms intended specifically for cases where randomized trials are not feasible. This followed other frameworks designed to speed up access to therapies targeting ultra-rare conditions.
Market research suggests ongoing regulatory evolution and targeted incentives continue driving growth; estimates project global orphan drug sales reaching $611 billion by 2032 compared with $247 billion last year.
However, experts caution that failure by Congress to act will undermine progress made so far. Williams concluded: “Long term… I think we’ll see less financial institutes actually investing in rare diseases… it’s going to really hit the rare disease industry quite hard.”
