- The Food and Drug Administration will convene an advisory committee to review FibroGen's experimental anemia drug roxadustat, the company announced Monday, likely forestalling a decision by the agency on the medicine's approval by a March 20 deadline.
- No date has been set for the meeting, FibroGen said. The FDA already extended its review of roxadustat, which is designed to treat anemia in people with chronic kidney disease, once before, pushing back its decision date from Dec. 20, 2020 to March 20.
- Shares in FibroGen fell by nearly a third in early Tuesday morning trading, erasing some $1.5 billion in market value. AstraZeneca, which is partnered with FibroGen on the drug, traded flat.
The FDA's last-minute scheduling of an advisory panel was an unexpected development for both FibroGen investors and the company.
"We're surprised by the timing of this request," Enrique Conterno, FibroGen's CEO, said on a conference call Monday, claiming the FDA had on several occasions indicated it was not planning to take such a step.
Conterno noted his company had been preparing last year for the possibility of an advisory committee meeting and now plans to "resume those preparation activities."
But the agency's surprising decision to call the meeting, particularly after extending its review, raised new questions about roxadustat's approval chances among analysts following the company.
"This announcement, and the complete lack of clarity about its implications, significantly lowers our confidence in overall approval for roxa[dustat] in [chronic kidney disease], but particularly in the non-dialysis setting where the risk-benefit tradeoff may be less clear to regulators," wrote Geoffrey Porges, an analyst at SVB Leerink, in a Tuesday note to clients.
The meeting, wrote Raymond James' Danielle Brill, indicates "there is still significant risk to approval."
Roxadustat, which is already approved in China and Japan, is a new type of medicine for treating anemia in chronic kidney disease patients. Known by scientists as a HIF-PH inhibitor, the drug promotes red blood cell production in a way that mimics the body's response to low-oxygen environments.
FibroGen and AstraZeneca aim to secure FDA approval for roxadustat in adult patients who are on dialysis and in those who are not. Their application is supported by data from a half dozen studies that enrolled over 8,000 patients.
Akebia and partner Vifor are developing a similar drug known as vadudstat, while both GlaxoSmithKline and Bayer are advancing would-be rivals. The medicines, which are pills, could offer an alternative to injectable drugs like Epogen and Aranesp. But their potential, particularly in the U.S., remains unclear. Akebia's drug, for instance, missed a critical safety measure in two Phase 3 studies, jeopardizing its future.
FibroGen and AstraZeneca are first to reach the FDA, which likely played into the regulator's decision to consult with a group of its outside advisers. But the late timing is unusual, FibroGen executives acknowledged in the Monday conference call.
"You can understand that people are, I guess, confused and a bit perplexed by the timing and also just the chronology of how things are played out," said Michael Yee, an analyst at Jeffries, on the call.
Outside of the U.S., China and several other countries, FibroGen is partnered with Japan's Astellas Pharma on roxadustat's development.