Sentinel cohort data from a pivotal infant trial rarely reach a major congress podium before the broader enrollment is complete, which makes Ascendis Pharma’s slot at ESPE 2026 worth watching closely. The company will present the first data from the reACHin Trial of TransCon CNP (navepegritide) in infants with achondroplasia at the European Society for Paediatric Endocrinology annual congress, running September 8-10 in Marseille.
The reACHin readout matters because it extends navepegritide’s tested age range down to infancy. The earlier pivotal ApproaCH Trial in older children with achondroplasia showed significant improvements in annualized growth velocity at 52 weeks. Infants represent a distinct population both biologically and from a regulatory standpoint: BioMarin’s Voxzogo (vosoritide) received FDA expanded approval in October 2023 to cover children from birth, so the infant segment already has an approved option, and any navepegritide data will face direct comparison against that established benchmark. The sentinel cohort design is an early safety and pharmacokinetic read in a small initial group; what ESPE attendees will actually see is whether the drug behaves predictably enough in very young patients to support continued enrollment rather than a full efficacy verdict.
Ascendis is also presenting updates from other endocrinology rare disease programs at the same congress, though the company has not detailed those datasets ahead of the meeting. Achondroplasia affects roughly 1 in 21,000 births globally, making each drug’s reach into younger age groups commercially meaningful even if the absolute patient numbers stay small. For a condition managed from birth onward, the ability to initiate treatment in the first months of life rather than waiting until age five is a genuine clinical question, not a line extension.
The number to track from the podium is whether the sentinel cohort safety profile supports dose progression to the full infant population in reACHin. That determination, more than any preliminary efficacy signal, controls how quickly the trial moves toward a dataset that could support a regulatory submission.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
