Efficacy and Safety of Burosumab Versus Oral Phosphate and Active Vitamin D Treatment in Pediatric Patients With XLH

Inclusion criteria

• . Male or female, aged 1 to ≤12 years with radiographic evidence of rickets as determined by central readers
• . Phosphate-regulating endopeptidase homolog, X-linked (PHEX) mutation or variant of uncertain significance in either the patient or in a directly related family member with appropriate X-linked inheritance
• . Biochemical findings associated with XLH: serum phosphorus \<3.0 mg/dL (\<0.97 mmol/L)
• . Serum creatinine below the age-adjusted upper limit of normal
• . Serum 25(OH)D above the lower limit of normal (≥16 ng/mL) at the Screening Visit
• . Have received both oral phosphate and active vitamin D therapy for ≥ 12 consecutive months (for children ≥3 years of age) or ≥ 6 consecutive months (for children \<3 years of age) 7 days prior to the Randomization Visit
• . Willing to provide access to prior medical records for the collection of historical growth and radiographic data and disease history
• . Provide written or verbal assent (as appropriate for the subject and region) and written informed consent by a legally authorized representative after the nature of the study has been explained, and prior to any research-related procedures.

Exclusion criteria