Yuviwel Gets FDA Greenlight as First Once‑Weekly Treatment for Dwarfism in Children

The FDA has approved Ascendis Pharma’s Yuviwel (navepegritide) for the treatment of achondroplasia, the most common form of dwarfism affecting bone growth. 

The approval introduces the first and only once‑weekly therapy designed to increase linear growth in children two years of age and older with open growth plates (epiphyses).

Related: Rare Disease Day 2026: From Breakthrough Therapies to a Brighter Future

Yuviwel was cleared under the FDA’s Accelerated Approval Program and received a Rare Pediatric Disease Priority Review Voucher.

Achondroplasia is a rare genetic condition characterized by disproportionate short stature and skeletal dysplasia, with the average height of an adult with achondroplasia approximately four feet. The disease can bring a range of medical complications involving the muscular, neurological and cardiorespiratory systems. Until now, treatment options were limited.

Individuals with achondroplasia have a gain-of-function mutation in the FGFR3 gene, which codes for FGFR3, leading to overactive protein signaling, which prevents normal bone growth. Achondroplasia occurs in approximately one in 10,000 to one in 30,000 live births per year.

Yuviwel provides continuous systemic exposure to C‑type natriuretic peptide (CNP) over the weekly dosing interval, a mechanism aimed at counteracting overactive FGFR3 signaling. The drug was developed as TransCon CNP.

Commercial availability of Yuviwel in the US is expected in early Q2 2026. 

Ascendis said the approval was supported by a clinical package for TransCon CNP submitted with the company’s New Drug Application (NDA), which included safety and efficacy data from three randomized, double-blind, placebo-controlled clinical trials and up to three years of open-label extension data.

The effectiveness of Yuviwel was demonstrated in a randomized, placebo-controlled 52-week trial with a subsequent 52-week open-label extension. The study enrolled 84 treatment-naïve children with genetically confirmed achondroplasia, with 57 receiving Yuviwel 0.1 mg/kg once weekly via subcutaneous injection and 27 receiving a placebo.

The primary endpoint was annual height growth. After 52 weeks, children treated with Yuviwel grew 1.5 cm more than those on placebo. During the open-label extension, patients continuing Yuviwel for a second year maintained this growth rate, supporting sustained efficacy over two years.

“We are confident in Yuviwel’s potential to transform the treatment of achondroplasia and are deeply grateful to patients, clinicians and advocates for their many contributions to this important milestone,” said Jan Mikkelsen, President and Chief Executive Officer at Ascendis Pharma in a company statement. “We have listened to advocacy groups for people with dwarfism to ensure we address what the community actually cares about. This reflects our ongoing commitment to pursue outcomes that patient communities have told us are important to them, and gives the achondroplasia community a new way to look at the promise of pharmacological treatment options.”

Ascendis has also established the Ascendis Signature Access Program (ASAP) to support patients and caregivers with access, education and assistance programs throughout the treatment process.

Ascendis will compete with BioMarin in achondroplasia, where BioMarin markets the daily CNP therapy, Voxzogo (vosoritide). The treatment generated $927 million in 2025, up 26% from the previous year and representing 29% of the company’s revenue. 

BioMarin is developing a long-acting Voxzogo successor, BMN 333, which has shown promising Phase I results with drug exposure levels more than three times those seen in other long-acting CNP studies. It could launch by 2030.

Yuviwel’s advantage is its once-weekly, sustained-release dosing, compared with Voxzogo’s daily injections. 

Meanwhile, BridgeBio and Kyowa Kirin reported positive Phase III results for infigratinib, an FGFR1-3 selective tyrosine kinase inhibitor, with approval expected later this year.

Analysts predict Yuviwel’s long-term potential to just hit a $1 billion peak for the CNP franchise. European markets and other potential indications, including combination therapies, could further expand Yuviwel’s reach.