Context: Vosoritide is the first approved targeted therapy for achondroplasia (ACH) based on increased annualized growth velocity in clinical trials. The aim of our project was an assessment of the real-world setting and treatment with vosoritide.

Design: This was a 12-month, retrospective observational study on an inception cohort of 34 patients with ACH treated with vosoritide.

Patients and methods: Thirty-four patients with ACH (22 males; aged 2.8 to 15.3 years at treatment initiation) who received vosoritide treatment for at least 12 months at a specialized clinic for skeletal dysplasia in childhood were included in the analysis. Auxological measurements at baseline and after 12 months of therapy were converted into disease-specific (ACH) and general population [Centers for Disease Control and Prevention (CDC)] z-scores. Physical function assessed by a 6-minute walk test was converted into z-scores and compared to an unaffected reference cohort.

Results: After 12 months of treatment, both ACH and CDC height z-scores showed significant increases, with mean changes (mean ± SD) of 0.52 ± 0.35 and 0.38 ± 0.44, respectively (both P < .0001). The annualized growth velocity exceeded reference values for untreated children with ACH. No significant changes were observed in body mass index, upper to lower body segment ratio (sitting height/height), or head circumference. The 6-minute walking distance improved, with z-scores increasing from -2.00 ± 1.12 to -1.39 ± 1.23 (P = .0215).

Conclusion: In a real-world setting, children with ACH showed significant improvements in growth and physical function after 12 months of treatment with vosoritide.

Keywords: CNP-analog; FGFR3; annualized growth velocity; growth; skeletal dysplasia.

© The Author(s) 2025. Published by Oxford University Press on behalf of the Endocrine Society.