Burden of Disease and Functional Impairment in XLH

NCT04946409 | Active Not Recruiting

• 1 other identifier: IdeFIX
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Observational study comprising prospective follow up as well as retrospective chart review in order to evaluate the longitudinal course of the disease in XLH patients with a specific focus on functional impairment, physical performance and complications associated with the disease or respective treatment.

Conditions

X Linked Hypophosphatemia

Outcome Measures

Primary Outcomes (1)

• Course of disease

  To document and assess the natural course of disease, associated symptoms and functional impairment in adult patients with XLH.

  retrospective and up to 48 months from enrollment

Secondary Outcomes (6)

• Comorbidities and medical treatment

  retrospective and up to 48 months from enrollment

• Functional deficits and mobility constraints

  retrospective and up to 48 months from enrollment

• Laboratory values

  retrospective and up to 48 months from enrollment

• Organ / tissue specific health issues

  retrospective and up to 48 months from enrollment

• Safety and tolerability of treatment

  retrospective and up to 48 months from enrollment

Other Outcomes (2)

• Impact of treatment on physical performance

  retrospective and up to 48 months from enrollment

• Medical history

  retrospective and up to 48 months from enrollment

Interventions

no intervention OTHER

no intervention

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult patients with X-linked Hypophosphatemia

You may qualify if:

• Male or female, aged ≥ 18 years, inclusive, at the time of enrollment
• Diagnosis of X-linked Hypophosphatemia confirmed by
• documented PHEX mutation in either the patient, or in a directly related family member
• positive family history of XLH and symptoms of the disease or
• Phosphaturia + elevated serum levels of c-term FGF23 or iFGF23 and symptoms of the disease
• Written informed consent

You may not qualify if:

• \- Suspected of confirmed diagnosis of another phosphate wasting disorder

Sponsors & Collaborators

• Wuerzburg University Hospital: lead
• Kyowa Kirin, Inc.: collaborator

Study Sites (1)

Orthopedic Center for Musculoskeletal Research, Orthopedic Department, University of Wuerzburg

Würzburg, 97074, Germany

Location

Biospecimen

Retention: SAMPLES WITHOUT DNA

Serum / Plasma / Urine

MeSH Terms

Conditions

Familial Hypophosphatemic Rickets

Condition Hierarchy (Ancestors)

Rickets, Hypophosphatemic; Rickets; Bone Diseases, Metabolic; Bone Diseases; Musculoskeletal Diseases; Hypophosphatemia, Familial; Renal Tubular Transport, Inborn Errors; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Male Urogenital Diseases; Metal Metabolism, Inborn Errors; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Metabolic Diseases; Nutritional and Metabolic Diseases; Calcium Metabolism Disorders; Hypophosphatemia; Phosphorus Metabolism Disorders; Vitamin D Deficiency; Avitaminosis; Deficiency Diseases; Malnutrition; Nutrition Disorders

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: OTHER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 22, 2021
• First Posted: June 30, 2021
• Study Start: October 1, 2020
• Primary Completion: November 30, 2024
• Study Completion (Estimated): October 1, 2026
• Last Updated: July 20, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

DE (1)