FDA Approves Vosoritide for Children With Achondroplasia

The FDA has approved a supplemental new drug application for vosoritide (Voxzogo; BioMarin Pharmaceutical Inc) to increase linear growth in pediatric patients with achondroplasia who have open epiphyses, known as growth plates. Previously, vosoritide was indicated for those aged 5 years and older, but the new indication includes all ages with open growth plates.

Vosoritide is a daily injection administered under the skin by a caregiver after a physician determines they are able to receive the drug. The physician will monitor the growth and determine when/if the patient is no longer able to grow, according to the statement.

"[Vosoritide] is the only approved treatment for children with achondroplasia. Until now, it has only been approved in the [United States] for children aged 5 and older with open growth plates," William Wilcox, MD, professor of human genetics at Emory University, said in a statement. "I am delighted that [vosoritide] is now approved for younger children where we hope to have potentially greater impact by starting treatment earlier and, as a result, a much longer treatment window."

The indication was granted accelerated approval based on the annualized growth velocity. Based on results of the Study 111-206 (NCT03583697) and Study 111-301 (NCT03197766), the safety and efficacy were well established in pediatric individuals who are any age with achondroplasia with open growth plates. Study 111-206 was a randomized, double-blinded, phase 2 clinical trial, which evaluated the safety and efficacy of the drug in children aged 5 years and older whereas Study 111-301 was a phase 3 study in pediatric individuals aged 5 years and older.

Furthermore, data from an open-label, long-term, phase 2 extension study, presented at the 2023 European Society for Paediatric Endocrinology Meeting, demonstrated a mean height Z-score improvement of 1.1 to 1.4 standard deviations and a mean height gain of 6.3 cm to 7.8 cm in children aged 2 years and older treated with vosoritide compared to those who were untreated with achondroplasia over 4 years. Additionally, children under 2 years of age who were treated with vosoritide for 3 years demonstrated a mean height Z-score improvement of 0.8 to 1.0 standard deviations and a height gain between 3.5 cm to 3.9 cm.

The most common adverse effects of vosoritide includes injection site reaction, high levels of blood alkaline phosphates, vomiting, joint pain, decreased blood pressure, and stomachaches.

Vosoritide is currently approved in Europe in children with achondroplasia aged 2 years and older with open growth plates. In September 2023, the European Medicines Agency’s Committee for Medicinal Products for Human Use recommended marketing authorization to expand the indication to treat children with achondroplasia aged 4 months and older with open growth plates. A final approval decision is expected later 2023.

Also, vosoritide is approved in Japan in children from birth with open growth plates. Additionally, it is approved in Brazil for children aged 6 months and older and Australia for children aged 2 months and older.

The FDA also granted vosoritide orphan drug designation for the treatment of hypochondroplasia, a genetic condition caused by a mutation in the fibroblast growth factor 3 gene, impairing bone growth. Though similar to achondroplasia, individuals with hypochondroplasia typically have milder disproportionality and less severe short statute, according to the statement.

Reference

US Food and Drug Administration approves BioMarin’s Voxzogo (vosoritide) for children under 5 years with achondroplasia. News release. BioMarin. October 20, 2023. Accessed October 23, 2023. https://investors.biomarin.com/2023-10-20-U-S-Food-and-Drug-Administration-Approves-BioMarins-VOXZOGO-R-vosoritide-for-Children-Under-5-Years-with-Achondroplasia