The US Food and Drug Administration's (FDA) rare pediatric disease priority review voucher program is slated to end in one year, after the agency awarded its third-ever rare pediatric voucher, thereby triggering a little-known provision in the voucher program.
Regular readers of Regulatory Focus will be familiar with FDA's priority review voucher programs. We've written about them extensively over the years, and the vouchers are the focus of our most recent Regulatory Explainer.
Read our extensive Regulatory Explainer on the Priority Review Voucher program here.
For the uninitiated, priority review vouchers are incentives meant to catalyze the development of new therapies for historically under-served disease areas, such as rare pediatric diseases affecting fewer than 200,000 children in the US.
Because rare pediatric diseases represent small numbers of patients, which can make it difficult for a company to recoup development costs even if their drug is approved, in 2012 legislators created a new incentive intended to attract new pharmaceutical development.
That incentive is a special voucher which allows its owner to have any experimental drug the company owns reviewed by FDA under its "priority review" pathway. The priority review pathway allows for the review of a drug in just six months instead of the standard 10 months—a valuable incentive for many, if not most, companies.
The voucher may also be sold to other companies. To date, two companies have sold priority review vouchers: one for $67.5 million, and another for $125 million.
A New Approval
On 17 March 2015, FDA awarded a new priority review voucher to Asklepion Pharmaceuticals upon the approval of its new drug, Cholbam (cholic acid). According to FDA, Cholbam is the first FDA-approved treatment for pediatric and adult patients with bile acid synthesis disorders due to single enzyme defects, and for patients with peroxisomal disorders.
The disease can result in life-threatening injuries to the liver, FDA explained in its approval notice.
Asklepion's decision to seek approval for Cholbam's pediatric indications won it a rare pediatric disease priority review voucher, and puts the company in rare company. FDA has awarded just six priority review vouchers in its entire history, including the one awarded to Asklepion Pharmaceuticals.
As per an earlier licensing agreement, Asklepion has transferred its priority review voucher to Retrophin, a San Diego-based pharmaceutical company.
A Little-Known Provision
Asklepion/Retrophin's new voucher is also unusual in another, little-known way.
When the rare pediatric disease priority review voucher program was created in 2012 under the Food and Drug Administration Safety and Innovation Act (FDASIA), legislators bundled it along with a sunset clause.
That clause reads:
The Secretary may not award any priority review vouchers under paragraph (1) after the last day of the 1-year period that begins on the date that the Secretary awards the third rare pediatric disease priority voucher under this section.
In plain terms: After FDA awards its third rare pediatric disease priority review voucher, a one-year countdown clock begins. After the year is up, FDA may no longer award any additional rare pediatric disease priority review vouchers. The vouchers themselves may still be redeemed.
According to statute, FDA's rare pediatric disease priority review voucher program is now slated to end after 17 March 2016.
Will Congress Act?
The impending end of the program will almost certainly attract the attention of House and Senate legislators, who are now working on FDA reform legislation under the auspices of the House of Representatives' "21st Century Cures" initiative.
The voucher program has strong support from the House Childhood Cancer Caucus, which put out a press release on 13 March 2015 reiterating its support for the program after the award of a priority review voucher to United Therapeutics for a pediatric drug.
Whether or not the program is reauthorized in whole or is subject to legislative changes remains to be seen.
FDA Approval Notice