BioMarin Pharmaceutical has obtained Japan’s Ministry of Health, Labor and Welfare (MHLW) approval of the registration for its Voxzogo (vosoritide) for injection to treat achondroplasia in children whose growth plates are not closed.

A modified C-type natriuretic peptide (CNP), Voxzogo acts on achondroplasia’s underlying pathophysiology.

It works by down-regulating fibroblast growth factor receptor 3 (FGFR3) signalling and subsequently boosting endochondral bone formation.

The latest approval is based on findings from an international, placebo-controlled, randomised, double-blind Phase III clinical trial assessing the efficacy and safety of Voxzogo.

The data also includes outcomes from the long-term extension of this trial and results from a placebo-controlled, randomised, double-blind Phase II trial analysing the safety and efficacy of Voxzogo in infants and young children with achondroplasia aged 0 to less than 60 months.

Data from the Phase III trial showed that treatment with Voxzogo offered transient declines in blood pressure.

Over a treatment period of 52 weeks, 13% of the trial subjects in the Voxzogo arm had a total of 11 events of transient declines in blood pressure versus 5% in the placebo arm.

BioMarin Pharmaceutical chairman and CEO Jean-Jacques Bienaimé said: “We -are delighted to offer children in Japan of all ages with achondroplasia access to a treatment option that addresses the underlying genetic mechanism of the condition. 

“CNP was discovered as a natural regulator of bone growth in Japan in 1990 so we are especially proud to be able to offer a therapeutic choice there.”

Voxzogo obtained approvals in Europe, the US and Brazil last year. 

Characterised by reduced endochondral bone growth, achondroplasia is the most common kind of skeletal dysplasia and causes disproportionate short stature.