Burosumab in Children and Adolescents With X-linked Hypophosphatemia

12-months of Treatment With Burosumab in Children and Adolescents With X-linked Hypophosphatemia: a Prospective Longitudinal Cohort Study

In this prospective longitudinal cohort study we studied the efficacy and safety of burosumab in real-clinical practice for <13- and >13-years old children affected with X-linked hypophosphatemia.

57 children with XLH were switched from conventional treatment to burosumab. After 12 months we assessed the efficacy and safety of treatment with burosumab on the whole cohort and separately on the cohort of >13-years old adolescents.

Study Overview

• Status: Unknown
• Conditions: Rare Diseases; X-linked Hypophosphatemia
• Intervention / Treatment: Drug: Burosumab Injection

• Study Type: Interventional
• Enrollment (Anticipated): 57
• Phase: Phase 4

Contacts and Locations

Study Locations

• France
  • Le Kremlin-Bicêtre, France, 94270
    • Recruiting
    • Hospital BICETRE
    • Contact: Volha Zhukouskaya, MD, PhD; Phone Number: +33766681018; Email: vzhukuskaya@genethon.fr
    • Principal Investigator: Agnès Linglart, MD, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 1 year to 20 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• insufficient response or refractory to conventional therapy;
• complications of conventional therapy: hypercalciuria and/or nephrocalcinosis, and/or persistent secondary hyperparathyroidism;
• need for rapid restoration of phosphate metabolism, e.g., late diagnosis (aged >8 years) and/or preparation for planned orthopaedic surgery.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: The whole cohort; Children affected with X-linked hypophosphatemia of average age of 9.8 years were switch from conventional therapy to burosumab	Drug: Burosumab Injection; Children affected with X-linked hypophosphatemia were switched from conventional therapy to burosumab

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Radiological changes in rachitic lesions evaluated with knee MRI	maximum width of the physis and transverse extent of widening	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
serum phosphate	mmol/l	12 months
renal phosphate reabsorption	mmol/l	12 months
alkaline phosphatase	U/l	12 months
1,25(OH)vitaminD	pg/ml	12 months
parathyroid hormone	ng/l	12 months
height	standard deviation score	12 months
functional capacity	6-minute walk test, standard deviation score	12 months
incidence of dental abcesses	dental examination	12 months
incidence of hearing problems	ORL examination, audiogramm	12 months
incidence of neurological problems (craniosynostosis, Chiari I malformation)	neurosurgical examination and brain MRI	12 months
incidence of nephrocalcinosis	renal ultrasound	12 months
incidence of hyperparathyroidism	blood levels of parathyroid hormone	12 months
incidence of any side effects	registration of any side effects during the treatment by telephone call	12 months

Collaborators and Investigators

• Sponsor: Bicetre Hospital

Study record dates

Study Major Dates

• Study Start (Actual): March 18, 2018
• Primary Completion (Actual): March 20, 2019
• Study Completion (Anticipated): September 16, 2022

Study Registration Dates

• First Submitted: May 29, 2020
• First Submitted That Met QC Criteria: June 3, 2020
• First Posted (Actual): June 5, 2020

Study Record Updates

• Last Update Posted (Actual): June 5, 2020
• Last Update Submitted That Met QC Criteria: June 3, 2020
• Last Verified: June 1, 2020

More Information

Terms related to this study

• Keywords: hyperparathyroidism; fibroblast growth factor 23; X-linked hypophosphataemia; burosumab
• Additional Relevant MeSH Terms: Pathologic Processes; Metabolic Diseases; Kidney Diseases; Urologic Diseases; Disease Attributes; Nutrition Disorders; Genetic Diseases, Inborn; Musculoskeletal Diseases; Avitaminosis; Deficiency Diseases; Malnutrition; Bone Diseases; Metabolism, Inborn Errors; Bone Diseases, Metabolic; Renal Tubular Transport, Inborn Errors; Calcium Metabolism Disorders; Metal Metabolism, Inborn Errors; Phosphorus Metabolism Disorders; Rickets; Vitamin D Deficiency; Rickets, Hypophosphatemic; Hypophosphatemia, Familial; Familial Hypophosphatemic Rickets; Hypophosphatemia; Rare Diseases
• Other Study ID Numbers: 20200528104746

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No