The pharmacokinetics of vosoritide and relationships between vosoritide plasma exposure and efficacy, biomarkers, and safety endpoints were evaluated in a phase II and a phase III study.

The exposure–response relationships for annualized growth velocity and an endochondral ossification biomarker saturated at exposures obtained at 15 μg/kg, while pharmacological activity was near maximal at exposures obtained at 30 μg/kg. No differences were observed in the safety profile of vosoritide between the two doses.

The results from these analyses support the recommended dose of 15 µg/kg vosoritide for once-daily subcutaneous administration in patients with achondroplasia aged ≥5 years whose growth plates are not closed.