Only months after its first-ever drug approval, rare disease biotech Ultragenyx is back with another FDA nod. On Tuesday, the FDA signed off on Crysvita to treat X-linked hypophosphatemia in patients one year and older.
The med, part of a collaboration with Japan's Kyowa Hakko Kirin, is set to dramatically improve care for the patient population, lead study investigator and Yale professor Tom Carpenter said in a statement. He called Tuesday's approval a "watershed moment" and predicted the drug would "revolutionize" care for the patients.
X-linked hypophosphatemia, or XLH, is a hereditary skeletal disease triggered by excess production of the hormone fibroblast growth factor 23. FGF23 causes phosphate urinary excretion and hinders patients' ability to produce vitamin D.
The drug treats the disease by blocking FGF23 and correcting phosphorus levels to improve bone health, according to Ultragenyx.
“By targeting this mechanism Crysvita leads to sustained improvements in phosphate metabolism with concurrent repair of the skeleton, even after prior treatment with conventional approaches," Carpenter said in the statement. "Most importantly, the dosing regimen for Crysvita is far less burdensome than for currently available therapies and should be readily acceptable by families."
Ultragenyx will price the drug at $160,000 per year in children and $200,000 per year for adults after rebates and discounts, Evercore ISI analyst Steve Breazzano wrote in a note to clients after the approval.
The analyst is modeling a slow ramp-up, with U.S. sales peaking at $1.1 billion in 2025. Part of the effort is to identify patients, according to Breazzano. The company says there are about 15,000 patients it can reach. For the launch effort, the company has hired 30 "patient diagnostic liaisons," Breazzano wrote, who will grow disease awareness and identify patients. Another 32 in the "UltraCare" staff will work on securing reimbursement.
The company doesn't expect to raise prices for the "first few years," according to the analyst; later price hikes will be in line with inflation, he wrote.
Ultragenyx and Kyowa Kirin entered their development partnership for the drug back in 2013. The deal covers U.S., Canada, Europe and Latin America; the drug already won European approval in children back in February.
The approval follows Ultragenyx's November nod for Mepsevii, its first-ever marketed drug, which treats mucopolysaccharidosis VII. With both approvals, the biotech won FDA rare pediatric disease priority review vouchers, which can be resold for a hefty sum. Large drugmakers will often pay a pretty penny for the vouchers in order to get a speedy FDA review for potentially lucrative drugs.
In fact, after the company's Mepsevii approval, it offloaded its voucher for that product to Novartis for $130 million.
Analysts have predicted about $75 million in peak sales for Mepsevii.