Vosoritide

Vosoritide, developed as BMN-111 and marketed as Voxzogo, modifies C-type natriuretic peptide. Achondroplasia results from overactive FGFR3 signaling that slows cartilage-cell growth at the growth plate. The medicine is designed to counter that inhibition. US approval began in 2021.

Binding natriuretic peptide receptor-B increases intracellular cyclic GMP in growth-plate cartilage cells and inhibits the overactive downstream FGFR3 pathway. Natural CNP lasts only minutes; the engineered analog lasts long enough for daily dosing.

In the Phase III trial, annual growth velocity was approximately 1.6 cm/year greater than placebo. The effect requires open growth plates. Transient blood-pressure lowering is a known pharmacological effect, so food and fluids are provided before administration.

FDA granted accelerated approval in 2021 for achondroplasia with open epiphyses, based on faster annual growth; continued approval may depend on confirmatory research. The initial age range was five years and older. Since October 2023, the indication covers children of all ages with open growth plates.

Daily subcutaneous treatment aims to improve linear growth and stops once plates close, because the mechanism depends on active bone growth.

Common effects include injection reactions, vomiting, transient hypotension and joint pain; rash is also common under age five. Low blood pressure is addressed by ensuring food and fluid intake before the dose and following the product-specific care plan.