BridgeBio Pharma has reported positive interim data from the Phase II PROPEL 2 clinical trial of the investigational therapy, infigratinib, in children with achondroplasia

Children aged as young as three years were enroled in the trial. 

According to the findings, the highest dose level of 0.128mg/kg once a day infigratinib offered a mean rise of 1.52cm/y in annualised height velocity (AHV) over baseline in children aged five years and above. 

Furthermore, 64% in this age group were found to be responders while a 60% average change from baseline in AHV was reported.

As indicated by preclinical findings, prior cohorts in this trial did not meet the target efficacious exposure and no dose response was reported. 

In children aged five years and above, a 0.22 cm/yr rise in AHV over baseline was reported across the prior combined cohorts.

At six months, the average rise in ACH height Z-score was found to be 0.21 standard deviation score (SDS) in children aged three to less than five years with a 0.61cm/y rise in AHV over baseline noted. 

In any cohort, no treatment-associated serious adverse events were observed so far. 

In addition, 90.3% of subjects had a minimum of one treatment-emergent adverse event with the majority being Grade 1. 

It was not linked to infigratinib and was in line with the paediatric achondroplasia population. 

Following talks with the regulatory authorities, the company commenced subject enrolment in Cohort 5 of the trial. 

Subjects in this cohort are given nearly twice the dose administered in Cohort 4.

An oral small molecule, infigratinib hinders FGFR3 and can act on achondroplasia at its source.

The company also plans to analyse infigratinib for various other FGFR-driven skeletal dysplasias based on the latest trial findings and preclinical data in hypochondroplasia.

BridgeBio Pharma founder and CEO Neil Kumar said: “These data, combined with our positive proof-of-concept data in LGMD2i and ADH1 earlier this year, highlight BridgeBio’s ability to efficiently prosecute high-value programmes in large areas of unmet need. 

“We look forward to exploring the potential of infigratinib in achondroplasia and related skeletal dysplasias in the near future.”