Navepegritide

iStock, master1305 If approved, Ascendis’ TransCon CNP would become the second therapy for achondroplasia, challenging BioMarin’s Voxzogo. The FDA has pushed the deadline out three months for its final decision on Ascendis Pharma’s achondroplasia treatment TransCon CNP. The delay comes after Ascendis in early November filed additional information regarding a post-marketing requirement for TransCon CNP. The FDA considered this a “major amendment,” according to a news release last Wednesday, necessitating the review extension. The agency’s original target action date was Nov. 30 , but Ascendis now expects the verdict to come on or before Feb. 28, 2026 . In a statement, Ascendis CEO Jan Mikkelsen said that the company has addressed “all outstanding requests from the FDA.” Ascendis will continue to work with the regulator to bring TransCon CNP to patients who need it “as soon as possible,” Mikkelsen added Achondroplasia is a genetic disease characterized by impaired bone development. The condition affects 15,000 to 40,000 newborns and qualifies as a rare disease, though it is known as the most common cause of dwarfism. TransCon CNP, also called navepegritide, specifically addresses the achondroplasia subtype caused by overactivity of the FGFR3 gene which, aside from compromising bone growth, also manifests with neurological, muscular and cardiorespiratory issues. Ascendis’ treatment gives patients the C-type natriuretic peptide (CNP), in turn counteracting the effects of mutated FGFR3 and helping to stimulate bone growth. Data from the Phase II ACcomplisH study published in The Lancet in November 2023, showed that TransCon CNP improved growth rates in patients with achondroplasia. The regulatory delay for TransCon CNP should give some breathing room to BioMarin, which owns Voxzogo, the only FDA-approved treatment for achondroplasia. That drug, approved in November 2021 , addresses the same disease pathway as TransCon CNP: it mimics the action of CNP and targets FGFR3 signaling, facilitating bone growth. BioMarin is increasingly wary of the incoming competition from TransCon CNP, alongside other investigational achondroplasia therapies on the horizon , including BridgeBio’s infigratinib. During its third-quarter earnings call in October, the company revealed that it will abandon its previously announced goal of hitting $4 billion in revenue in 2027, with CFO Brian Mueller specifically citing the “impact of potential Voxzogo” competition.

Analysts said a delayed decision on Ascendis Pharma’s dwarfism drug candidate TransCon CNP is unexpected, but they continue to expect approval.\n The FDA has delayed a decision on Ascendis Pharma’s dwarfism drug candidate TransCon CNP, pushing back the deadline by three months to buy time to review recently submitted information.Having accepted TransCon CNP for priority review, the FDA originally planned to make an approval ruling by Nov. 30. However, with days to go until the deadline, Ascendis revealed the FDA has delayed its decision. The delay will give the FDA time to review information the company filed Nov. 5 regarding its post-marketing requirement (PMR). The new decision deadline is Feb. 28, 2026.Ascendis CEO Jan Mikkelsen said in a statement that the FDA’s request for a revised protocol for the post-marketing study was “the lone item for discussion at our late-cycle meeting.” TD Cowen analysts flagged the “lone item” comment as a positive in a note to investors about the prospects of approval in the dwarfism condition achondroplasia. The analysts said the delay is unexpected, but they continue to expect approval given the FDA’s lone request was a protocol revision for the PMR. The requirement for a post-market study is a condition of the accelerated approval pathway. Based on the absence of a request for clinical data, the analysts said the FDA “is likely comfortable with the efficacy and safety” seen in Ascendis’ phase 3 trial.  Ascendis’ executives were surprised the Nov. 5 submission was deemed a major amendment, according to the analysts. The analysts surmised that the FDA likely has not had enough time to review the protocol and revert with comments. As the analysts noted, the delay “is somewhat consistent with a recent trend of delays considering staffing cuts at the FDA.”Days before the delay, the analysts said their base case is that the FDA approves TransCon CNP for use in children aged 2 to 11 years old. In the post-delay note, the analysts said they are encouraged that Ascendis’ management seems happy with the likely future label. The analysts speculated the upbeat outlook of the executives means the FDA could grant approval in a broader age group.Ascendis’ phase 3 trial enrolled children aged 2 to 11 years. The analysts cited the precedent set by the FDA’s approval of BioMarin’s Voxzogo—which received a broad age label despite not showing statistical significance in people aged 11 to 15 years old—to make the case that the agency might allow TransCon CNP use in older children.“This is an important age group as the bone plates typically do not fuse until mid-teenage years,” the analysts said. “Hence, we wonder if the PMR will include collecting registry data across various age groups while the label allows for use in a broader age group ≥2 y/o.” If approved, TransCon CNP will compete with Voxzogo. TransCon CNP is a once-weekly prodrug of C-type natriuretic peptide (CNP), a molecule that accelerates children\'s growth. Voxzogo is a CNP analog that is injected once a day. The analysts said the phase 3 data on TransCon CNP and Voxzogo look similar, but Ascendis’ weekly dosing and absence of hypertension could give it an advantage. BioMarin is racing to defend its territory. The biotech shared phase 1 data on a once-weekly successor to Voxzogo in August. BioMarin R&D chief Greg Friberg, M.D., said at the time that the drug candidate achieved area-under-the-curve levels greater than three times those reported for another long-acting CNP.