Aimmune drug application confusion leaves investors searching for answers
- Investors in Aimmune Therapeutics were caught off guard earlier this week when the biotech disclosed its application for approval of an experimental peanut allergy treatment would not be reviewed by the Food and Drug Administration due to the ongoing government shutdown.
- Tweets from FDA Commissioner Scott Gottlieb since raised further confusion, suggesting Aimmune and the agency had differing views of whether the biotech's drug was covered by user fee agreements that govern regulatory review — a technical detail that has consequential implications for Aimmune's path to market during a partial shuttering of the federal government.
- "To have this come up now seems very strange," said Credit Suisse analyst Vamil Divan, noting in an interview that he would have expected Aimmune and the FDA to agree on whether the drug was covered by user fee agreements before the biotech filed for approval. For its part, Aimmune says it has sought clarification from the regulator but has not yet received a definitive answer.
Aimmune thought it had submitted its application just in time.
On Dec. 21, one day before a lapse in funding shut down large parts of the U.S. government, the California-based biotech filed a Biologics License Application for AR101, its oral therapy for peanut allergy. Along with its submission, Aimmune paid a user fee to the FDA, believing the compound to be covered under Prescription Drug User Free Act agreements between the regulator and industry.
That's important, because the FDA has said it will continue to review through the shutdown drug applications for which user fees were already submitted prior to Dec. 22.
But, on Jan. 14, Aimmune notified investors in a regulatory filing that it had received notice from the FDA that the agency could not begin review of its BLA for AR101 — surprising investors and causing shares in the company to fall.
The FDA doesn't comment on pending applications, but tweets from FDA head Scott Gottlieb the following day suggested AR101 may not be covered by user fee agreements due to being an allergenic product.
"For products not covered by a user fee program, like most blood and allergenic extract products," the agency chief wrote, "FDA does not have carryover user fee funding to continue reviewing pending or accepting new applications."
Aimmune, however, argues that AR101 is not an extract and, in seeking approval, expected the therapy to be considered under the user fee pathway. The drug's active ingredient is defatted peanut flour and is designed to desensitize patients allergic to peanuts over time.
Gottlieb further muddied the waters with another tweet:
"Setting aside any particular matter specific to any one company, sometimes it's the case that companies will try to file under pathways that aren't open to them," the commissioner wrote, adding that "when confusion does occur by sponsors it's highly unfortunate."
A spokesperson for the FDA said via email the agency did not have any more information to share at this time.
"I think the FDA views this filing one way and [Aimmune views] it a different way," said Divan. Credit Suisse data shows that allergen extract tablets previously submitted via a BLA, but not covered by user fees, have taken between 13 months and 15 months to be reviewed.
"AR101's Fast Track Status and Breakthrough Designation may still allow for a more rapid approval, once the government reopens and the FDA is able to proceed with the review," Divan wrote in a Jan. 17 note to investors.
Putting aside classification, as it stands Aimmune's application isn't being reviewed. And that's weighed on the company's stock, which has fallen by more than 12% this week since Aimmune's disclosure.
Follow Ned Pagliarulo on Twitter