Real-World Growth Outcomes of Vosoritide in Children with Achondroplasia: A Single-Center Cohort Study

Abstract Introduction Vosoritide, a C-type natriuretic peptide analogue, is the first approved therapy targeting the pathophysiology of achondroplasia. While clinical trials demonstrate efficacy, individuals with prior orthopedic surgeries are typically excluded, and real-world data remain limited. Materials and Methods This retrospective analysis included 25 children with achondroplasia (17 boys, age range 2.9-14.3 years) treated with vosoritide for a mean duration of 12.7 months at a multidisciplinary center. Z-scores were calculated using an AI-assisted growth assessment tool previously validated for children with achondroplasia. Δ z-scores for height, sitting height, arm span, and body mass index (BMI) were calculated from baseline to follow-up. Multiple linear regression analyses assessed predictors of response. Results Mean height z-scores improved from -0.62 ± 1.09 to -0.24 ± 1.20 (p < 0.001). Mean arm span z-score increased from -1.28 ± 0.93 to -0.96 ± 0.91 (p=0.007). Sitting height z-scores showed a non-significant trend toward improvement; BMI z-scores remained stable. Mean Δ height and Δ arm span z-score gains were +0.38 ± 0.45 and +0.32 ± 0.48, respectively. A subgroup analysis of 8 patients with versus 17 without prior limb-lengthening surgery showed no significant differences. Regression analyses adjusted for sex, age, BMI z-scores, and surgical history were likely underpowered to detect meaningful predictors of response. There were no serious treatment-related adverse events. Conclusions Vosoritide therapy enhanced linear and appendicular growth in a real-world cohort of children with achondroplasia, including post-surgical patients. These findings align with clinical trial data and support the therapy’s applicability across diverse clinical profiles.