Overview

This is a long-term, multicenter, non-interventional study of children ages 2.5 to <17 years with hypochondroplasia (HCH).

Eligibility

Inclusion Criteria:

Signed informed consent.

Aged 2.5 to <17 years at study entry.

        Diagnosis of HCH documented clinically by the presence of disproportionate short stature
        and confirmed with a molecular test.
        Participants are ambulatory and able to stand without assistance.
        Study participants and parent(s), guardian(s), or caregiver(s) are willing and able to
        comply with study visits and study procedures.
        Exclusion Criteria:
        Have ACH or short stature condition other than HCH.
        In females, having had their menarche. Annualized height growth velocity ≤1.5 cm/year over
        a period ≥6 months prior to screening.
        Having a clinically significant disease or condition that in view of the investigator or
        Sponsor will interfere with the evaluation of growth, with study participation or not be in
        the best interest of the participant.
        Clinically significant abnormality in any laboratory test result at screening
        Have been treated with growth hormone, IGF 1, or anabolic steroids the previous 6 months or
        long-term treatment (>3 months) at any time.
        Current evidence of corneal or retinal disorders.
        Have used any other investigational product or investigational medical device for the
        treatment of HCH or short stature.
        Have had regular long-term treatment (>1 month) with oral corticosteroids (low-dose ongoing
        inhaled steroid for asthma is acceptable).
        Previous limb-lengthening surgery or guided growth surgery with plates still in place or
        removed within the 6 months prior to screening.
        Having had a fracture of the long bones or spine within 12 months of screening.
        History and/or current evidence of extensive ectopic tissue calcification.
        History of malignancy.
        Concurrent circumstance, disease, or condition that, in the view of the investigator and/or
        sponsor, would interfere with study participation, and/or would place the participant at
        high risk for poor compliance with study activities or for not completing the study.