FDA OKs treatment for kids with achondroplasia

The US Food and Drug Administration (FDA) has given accelerated approval to BioMarin Pharmaceutical Inc. for VOXZOGO™ (vosoritide) for Injection, which is used to increase linear growth for children with achondroplasia who are aged 5 years and older and have open epiphyses.¹ Continuation of this approval could be contingent upon studies that confirm clinical benefit. The drug is C-type natriuretic peptide analog and is the first FDA-approved drug for children with achondroplasia.

Approval was awarded on the basis of the results from a global randomized, double-blind, placebo-controlled Phase 3 study that studied the safety and efficacy of vosoritide as well as an open-label extension of the study. Investigators enrolled 121 children aged t to 14.9 years who had achondroplasia. At baseline, the average annualized growth velocity was 4.06 cm/year in the placebo arm and 4.26 cm/year in the Voxzogo arm. At week 52 the change from baseline was -0.17 cm/year for the placebo treated patients and 1.40 cm/year for the Voxzogo treated patients. Following the completion of the 52 week study, 58 participants from the intervention arm were enrolled in the open-label extension. Improvement in annualized growth velocity was found to be sustained among the children who had 2 years of follow-up after being randomized.

Transient blood pressure decreases were noted in the treatment group with 8 patients experiencing 11 episodes whereas only 3 patients had 3 episodes in the placebo group. Children who either had significant cardiac or vascular disease or were on an antihypertensive therapy were not included. Proper hydration and adequate food can mitigate this risk. The most common adverse events included injection site reactions, vomiting, gastroenteritis, diarrhea, dizziness, ear pain, fatigue, and dry skin.

The therapy is expected to be available for use in the last couple of weeks of 2021.

Reference

BioMarin Pharmaceutical Inc. BioMarin receives FDA approval for VOXZOGO™ (vosoritide) for injection, indicated to increase linear growth in children with achondroplasia aged 5 and up with open growth plates. Published November 19, 2021. Accessed November 22, 2021. https://investors.biomarin.com/2021-11-19-BioMarin-Receives-FDA-Approval-for-VOXZOGO-TM-vosoritide-for-Injection,-Indicated-to-Increase-Linear-Growth-in-Children-with-Achondroplasia-Aged-5-and-Up-with-Open-Growth-Plates