Posted 31 July 2014
By Alexander Gaffney, RAC
As far as regulatory incentives go, some are pursued more than others. The US Food and Drug Administration's (FDA) orphan drug exclusivity provisions, for example, have brought about a renaissance of therapies meant to treat patients suffering from rare diseases and conditions.
But on the other side of the coin are incentives not often sought out by companies. And perhaps no incentive maintained by FDA is used less than its priority review vouchers.
FDA currently maintains two priority review voucher systems: one known for tropical diseases, and the other for pediatric rare diseases.
The tropical disease priority review voucher system was established under the FDA Amendment Act of 2007 (FDAAA). Under the system, companies that receive approval for a tropical disease treatment are eligible to receive a transferrable voucher that allows the bearer to receive six-month priority review status for any future product. Products undergoing priority review are generally given an approval decision—positive or negative—within six months after the applicant's filing date.
The legislation was enacted to spur development of treatment options for tropical diseases, which FDA notes have been remarkably stagnant over the last half century. "Because these diseases are found primarily in poor and developing countries, existing incentives have been insufficient to encourage development of new and innovative drug therapies," explained FDA in a 2008 guidance document on the subject. FDA said it was taking an interest in the topic given the needs of other countries and the ability of those diseases to affect Americans in an increasingly globalized economy.
Under normal circumstances, FDA only grants priority review status to products which fill a treatment void or would otherwise represent a significant advancement compared to existing treatments. Because these reviews cost more than traditional drug reviews, the cost per application is more. However, under the voucher program, any company willing to pay the additional cost of the review may have its product reviewed by FDA, the agency explained.
FDA typically reviews priority review applications within six months, instead of the standard 10 months.
Limits on Tropical Vouchers: Time and Cost
But the tropical disease voucher system hasn't been used much, in part because it's somewhat restrictive. As FDA explains in its guidance document on the voucher, "the sponsor redeeming the voucher must notify FDA of their intent to submit a human drug application with a priority review voucher at least 365 days prior to submission of the human drug application for which a priority review voucher will be used to obtain a priority review." That advance review time makes it impractical for many companies, which may not be willing to purchase a voucher until they know their product will be able to submitted to FDA.
And just as important, some drugs simply won't benefit from a faster review from FDA. For example, if a drug has outstanding questions that must be answered, the voucher might simply facilitate a quicker complete response letter (CRL).
And in addition to the purchase price of the voucher from another company, users of the vouchers must also pay FDA to use them—$2,325,000 per voucher as of FY 2014.
A New Voucher System
FDA has also recently established a second priority review voucher system: the rare pediatric disease priority review voucher program.
The first rare pediatric disease voucher was given to the pharmaceutical company BioMarin in February 2014 after its rare disese drug Vimizim was granted FDA approval. While FDA is still in the process of writing a guidance on the pediatric voucher program, the program, which was established under the 2012 FDA Safety and Innovation Act (FDASIA), contains a notable improvement over the tropical disease voucher program.
Unlike the 365-day waiting period to use a tropical disease voucher, a pediatric rare disease voucher can be used just 90 days after notifying FDA of a company's intent to use it (Section 529).
First Voucher, First Intended Use
And now BioMarin is marking another first as well: the first sale of a rare pediatric disease voucher.
On 30 July 2014, BioMarin announced that it had sold its voucher to Sanofi and Regeneron for $67.5 million.
The "novel bet" made by Sanofi and Regeneron is that the faster review time for their prospective blockbuster PCSK9 cholesterol drug, alirocumab, will pay off in increased revenue through accelerated market access—assuming the drug is approved in six months. Whether it is will mean the difference between a "bet" that pays off and an expensive blunder that adds tens of millions to the cost of the drug's development.
Sanofi and Regeneron also announced on 30 July that alirocumab had successfully completed nine late-stage trials, meaning the company likely believes it has the evidence necessary for FDA to reach a successful review decision.