Treating Achondroplasia: results from the fourth cohort of the phase 2 study with vosoritide have been released

Biomarin, the developer of vosoritide published a press release today describing results of the fourth cohort of the phase 2 study. 

In brief, the dose of the fourth cohort, 30mcg/kg/day, although safe, was not superior to the dose of the third cohort (15mcg/kg/day), so the developer decided to use 15mcg/kg/day as the dose for the upcoming phase 3 study.

Below, I reproduce the tables showing the main results divulged today.

*Children increased dose to 15 µg/kg/day after at least 6 months at 2.5 and/or 7.5 µg/kg/day; 4 of original 16 subjects in Cohorts 1 and 2 did not initiate dosing at 15 µg/kg/day due to subject decision to withdraw from the study (2), declining extension study (1), and growth plate closure (1)

**One child in cohort 4 discontinued from treatment due to finding of a rare congenital abnormality of conduction identified on routine study of ECG monitoring, which was not associated with symptoms, and patient was removed from treatment for precautionary reasons.

* Nominal p-value, not adjusted for multiplicity
** Mean Annualized Growth Velocity change from baseline increases to 2.0 cm/year (50% increase) if one patient who missed majority of doses between 6 and 12 months is excluded
***8 children have non-missing annualized growth velocity at both baseline and 6 months.

You can find the complete press release here.