Are priority review voucher programs stimulating drug development? The data suggest not really, finds GAO report
What is the impact of the three priority review voucher programs (PRV) on drug development? Not much, according to data analyzed by Congressional watchdog GAO.
PRV programs offer companies a perk in the form of a voucher when a new treatment — in the field of rare pediatric disease, tropical disease or medical countermeasure — is approved. These vouchers can be used to hasten the review of another drug or be sold. Altogether, the three programs: tropical disease PRV (authorized in 2007), the rare pediatric disease PRV (sanctioned in 2012) and the medical countermeasure PRV (backed in 2016) have led to the deployment of a total of 31 PRVs — of which 17 have been sold for varying sums, ranging from $67.5 million to $350 million.
After conducting a literature review, the GAO found some largely disheartening data on their impact on drug development. A 2017 study found that not only did the tropical disease PRV program not rejuvenate the pipeline for tropical disease drugs — but that the proportion of tropical disease drugs among all drugs-in-development actually fell a smidge following the creation of the PRV program. A 2018 study found that considering the majority of medical countermeasures under clinical development already get direct or indirect federal funding, alternatives other than the PRV program could better stimulate drug development in the field.
And finally, a 2019 study found that although the rare pediatric disease PRV program did not enhance the number or rate of new pediatric disease drugs that started or completed clinical trials, drugs that could be eligible for a rare pediatric disease PRV were more likely to advance from Phase I to Phase II clinical trials when compared to rare adult disease drugs.
But when GAO spoke to a slew of drugmakers, the reactions to incentives offered by PRV programs were largely positive, suggesting that the PRV programs were a factor in drug development decisions. Researchers, on the other hand, had mixed reviews. Overall, drug sponsors, researchers and other stakeholders suggested that the sheer number of PRVs awarded, and the declining revenue from their sales, could impact the programs’ ability to incentivize. There was no consensus on whether the rare pediatric disease and medical countermeasure PRV programs — set to expire by 2022 and 2023 — should be reauthorized.
Prescriptions for improvement were also offered. Some stakeholders took issue with the way the tropical disease PRV is awarded — because it can be given to compounds that have been previously approved outside the United States once they are sanctioned for use in the United States. For example, Novartis won a PRV after securing FDA approval for Egaten, a treatment for fascioliasis in 2019 — even though the drug has been on the WHO’s essential medicines list since 2002 and has been approved well before 2019 in other regions.
Another loophole criticized was that drugmakers awarded a PRV have no obligation to make the approved drug available at an affordable price — and some suggested that a mandated access plan that accompanies the PRV could enhance access for populations that need it. Some stakeholders also suggested awarding PRVs to financially strapped organizations, like non-profits, to offset development costs.