Daily tablet shows promise in treating achondroplasia in children

A promising daily tablet is effective at increasing height and improving proportional limb growth in children with achondroplasia, the most common form of dwarfism, according to a new study. And the findings could spare these children from needing to have a daily injection to boost growth.

The phase II study, led by Murdoch Children's Research Institute (MCRI) and published in the New England Journal of Medicine, found the drug infigratinib, an investigational product, was safe and effective in treating children with achondroplasia aged 3-11 years.

MCRI Professor Ravi Savarirayan said infigratinib not only boosts bone growth but also improves the quality of life for these children.

The study, sponsored by BridgeBio Pharma Inc, involved 72 children with achondroplasia from Australia, the UK, the US, Spain, France and Canada. It reported the medication was effective at increasing the rate of growth by 2.5cm a year for up to 18 months during treatment, increasing overall height and improving the upper-to-lower-body segment ratio. Participants experienced minor side effects from the treatment but none had serious adverse reactions.

Currently, the only approved therapy for children with achondroplasia in Australia is vosoritide, a daily injection, which was added to the PBS last year. MCRI is the largest vosoritide clinical trial site in the world. Professor Savarirayan and his research team have previously shown how the drug improves bone growth development in patients as young as four months up until 18 years of age.

Our new study found that infigratinib is a safe and effective drug that increases growth in children with achondroplasia and could meet a need for an oral medication for those with this condition. This is especially important for those children who can't tolerate daily injections and in parts of the world where oral medications are more practicable than injections."

Ravi Savarirayan, MCRI Professor

Achondroplasia is the most common form of skeletal dysplasia or dwarfism, affecting around one in 20,000 babies in Australia. The genetic condition can cause serious medical complications such as spinal cord compression, sleep apnoea, bowed legs, narrowing of the spinal canal and recurrent ear infections. Children with achondroplasia are 50 times more likely to die before the age of five than their peers.

Professor Savarirayan said the team had started a phase III trial and planning was underway into further studies into children aged 0-3 years with achondroplasia.