TransCon CNP PDUFA delay likely a speed bump to approval

Cantor Fitzgerald analysts have connected with Danish biotech Ascendis Pharma’s (Nasdaq: ASND) on the three-month Prescription Drug User Fee Act (PDUFA) extension of TransCon hGH) CNP (navepegritide) for achondroplasia, which is now scheduled for February 28, 2026.

The good news is that the only issue cited was the post-marketing study protocol, which was submitted to the Food and Drug Administration (FDA) on November 5, 2025. The agency raised no concerns about the data package or CMC — a potential worst-case scenario that would have required a longer resolution timeline, the analysts noted.

The post-marketing requirements appear to be a minor issue to us, and they suspect that it's possible the extension is partially caused by capacity constraints and Thanksgiving week at the FDA. Ascendis noted there had been no prior indication of a delay until the notification was received on Tuesday.