Clinical Research Directory

Inclusion Criteria: * Participants must have ACH with a confirmed mutation in the FGFR3 gene * Participants and/or parent(s) or legal representative(s) must be willing and able to perform all the study procedures to the best of their physical ability. * Parent(s) or legal representative(s) capable of giving signed informed consent and participants capable of giving assent when applicable. Exclusion Criteria: * Have hypochondroplasia (or the N540K mutation) or short stature condition other than ACH (eg, trisomy 21, pseudochondroplasia) * Participants have received any dose of medications or investigational product, including human growth hormone, IGF-1, intended to affect participants' stature or body proportions between the completion of OBS16647 and enrollment (Week 0/Day 1/Visit 2). * Have a history of growth plate closure. * Long bone fracture within 3 months of enrollment (Week 0/Day 1/Visit 2) * Current evidence of corneal or retinal disorder/keratopathy. * Participants have had a previous surgical intervention involving the foramen magnum (Stage 2 only). * Hyperphosphatemia. The above information is not intended to contain all considerations relevant to a potential participation in a clinical trial.