Study of Longitudinal Observation for Patient With X-linked Hypophosphatemic Rickets/Osteomalacia in Collaboration With Asian Partners

Conditions

X-Linked Hypophosphatemia

Keywords

XLH

Brief summary

Through observation of patients with X-linked hypophosphatemic rickets/osteomalacia (XLH) for up to 10 years, the study intends to collect data that allow achievement of the following objectives: 1. To determine medical characteristics of the disease and the disease process 2. To determine physical and psychological burden on patients as well as economic burden 3. To assess the efficacy and safety of the treatment of the disease

Seiji Fukumoto, Dieter Haffner, Erik A. Imel, Keiichi Ozono, M L Brandi et al. (13 authors)

The Journal of Clinical Endocrinology & Metabolism2026-03-30

10.1210/clinem/dgag136

Distribution of blood pressure and its positive association with body mass index standard deviation score in pediatric patients with X-linked hypophosphatemia: a sub-group analysis from the SUNFLOWER observational study.

Fujiwara K, Kabata D, Kawai R, Kang HG, Namba N, Ito N, Shintani A, Fukumoto S, Ozono K, Michigami T.

2025-10-04

10.1507/endocrj.ej25-0179

Advancing Patient Evidence in XLH (APEX): Baseline analysis of a global data unification program

Thomas O. Carpenter, Seiji Fukumoto, Dieter Haffner, Erik A. Imel, Keiichi Ozono et al. (13 authors)

Bone2025-09-17

10.1016/j.bone.2025.117649

Advancing patient evidence in XLH (APEX): rationale and design of a real-world XLH global data unification program

Maria Luisa Brandi, Thomas O. Carpenter, Seiji Fukumoto, Dieter Haffner, Erik A. Imel et al. (8 authors)

Frontiers in Endocrinology2025-04-071 citations

10.3389/fendo.2025.1471127

Prevalence of Comorbid Hyperparathyroidism and Its Association with Renal Dysfunction in Asian Patients with X-Linked Hypophosphatemic Rickets/Osteomalacia.

Ito N, Kang HG, Michigami T, Namba N, Kubota T, Shintani A, Kawai R, Kabata D, Ishii H, Nishida Y, Fukumoto S, Ozono K.

2025-03-121 citations

10.1007/s00223-025-01359-9

Long-term outcomes for Asian patients with X-linked hypophosphataemia: rationale and design of the SUNFLOWER longitudinal, observational cohort study

Takuo Kubota, Seiji Fukumoto, Hae Il Cheong, Toshimi Michigami, Noriyuki Namba et al. (9 authors)

BMJ Open2020-06-0113 citations

10.1136/bmjopen-2019-036367

Interventions

OTHERno intervention

no intervention

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Healthy volunteers

No

Inclusion criteria

* Patients must meet at least one of the following: 1. Documented PHEX gene mutation 2. Documented PHEX gene mutation in at least one family member with X-linked genetic relationship 3. Documented FGF23 \>30 pg/mL * Typical clinical findings of rickets/osteomalacia * Written informed consent obtained from patients aged \>=18 years or from parents or legally acceptable representatives of patients aged \<18 years

Exclusion criteria

* Participation in any clinical study (trial) at the time of informed consent * Any patient whose participation in the study is considered inappropriate by the investigator or the subinvestigator

Design outcomes

Primary

Measure	Time frame	Description
Height	After enrollment, patients will be observed annually or every 2 years for up to 10 years.	Height in centimeters
The 6-Minutes Walking Test	After enrollment, patients will be observed annually for up to 10 years.	The 6-Minutes Walking Test performed according to International Guidelines, will be measured as distance in meters.
Timed Up and Go Test(TUGT)	After enrollment, patients will be observed every 2 years for up to 10 years.	The time required for each patient to do the TUGT will be recorded: Stand up from sitting in a chair, walk 3 meters, turn around, walk back, and sit down.

Secondary

Measure	Time frame	Description
Fracture	10 years	Incidence of fracture of all parts
Radiography	After enrollment, patients will be observed annually or every 2 years for up to 10 years.	Radiography of the sites listed below will be performed. AP views of both knees, PA vies of both wrists, and both long legs. Sites with symptoms such as pain, sites of suspected fracture, and spine (cervical, thoracic and lumber).
Nephrocalcinosis	After enrollment, patients will be observed annually or every 2 years for up to 10 years.	The renal ultrasound will be performed and the presence and/or progression of nephrocalcinosis will be measured.

Countries

Japan

Outcome results

None listed