Ascendis wins US approval for therapy for children with dwarfism

By Sahil Pandey and Puyaan Singh

Feb 27 (Reuters) - The U.S. Food and Drug Administration on Friday approved Ascendis Pharma's A71.F once-weekly therapy for children with a rare genetic disorder that causes dwarfism, the company said.

The treatment, branded Yuviwel, is a once-weekly injection designed to provide sustained exposure to C-type natriuretic peptide, which Ascendis said can counter growth-limiting effects driven by the FGFR3 mutation in achondroplasia.

Ascendis said continued approval for Yuviwel may depend on confirmation of clinical benefit in post-approval trials.

Achondroplasia is the most common type of short-limbed dwarfism. The condition occurs in 1 in 15,000 to 40,000 newborns, according to the National Institutes of Health.

The disorder is caused by a genetic mutation that affects a protein in the body called fibroblast growth factor receptor 3, or FGFR3, resulting in dwarfism.

Ascendis said it plans to launch Yuviwel in the United States in the early second quarter of 2026.

The FDA approval was based on results from Ascendis' 52‑week study in children aged 2 to 11.

The results showed a statistically significant improvement in annualized growth rate versus placebo, the company said.

BioMarin Pharmaceutical's BMRN.O injection, Voxzogo, is the only other approved drug for the condition.

While Voxzogo requires daily dosing, Ascendis' therapy was developed as a weekly shot.

Around 20% of patients do not do well on Voxzogo and could consider switching, TD Cowen analyst Yaron Werber said. Werber estimates 772 million euros in peak sales for Yuviwel in 2032.

BridgeBio Pharma BBIO.O earlier this month said its experimental therapy boosted growth rates in children with a rare genetic disorder that causes dwarfism.