BioMarin Pharmaceutical has reported positive results from a Phase II proof-of-concept and dose finding study of BMN 111 (vosoritide) in children with achondroplasia, a common form of human dwarfism.

Vosoritide is an analogue of C-type Natriuretic Peptide (CNP) that is being studied in children with achondroplasia under the age of 18 years as their bones are still amenable to growth.

In the trial, data from the 26 children showed a favourable safety profile and efficacy at the 15µg/kg/daily dose.

The ten children in cohort three treated with 15µg/kg a day had a mean increase of 50% in their annualised growth velocity compared against annualised prior six month natural history baseline growth velocity, according to the company.

BioMarin clinical development vice-president Dr Wolfgang Dummer said: "In children receiving the highest dose of 15µg/kg daily, we observed a 50% increase in mean annualised growth velocity compared to their own natural history control growth velocity.

The Phase II trial was an open-label and sequential cohort dose-escalation study of BMN 111 in children with achondroplasia, with an average age of 7.8 years.

Patients have been treated with either 2.5µg/kg/daily, 7.5µg/kg/ daily or 15µg/kg/ daily, respectively, in this three dose cohort study.

All subjects participating in the study were now been switched to the highest dose of 15µg/kg/ daily for the duration of the 18 month extension study, based on the safety profile observed to date across the three dose cohorts.

BioMarin chairman and CEO Jean-Jacques said: "It is estimated that about 96,000 patients in our established territories are afflicted with achondroplasia, so approximately 25%, or 24,000, are under 18 years of age and in our addressable market."