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A Study of KRN23 in Adult and Pediatric Patients with X-linked Hypophosphatemic Rickets/Osteomalacia

Phase 3 Long-term Extension Study of KRN23 in Patients with X-linked Hypophosphatemic Rickets/Osteomalacia and a Post-marketing Study of KRN23 Switched from the Phase 3 Long-term Extension Study

Status
Active, not recruiting
Phases
Phase 3
Study type
Interventional
Source
JPRN
Registry ID
JPRN-jRCT2080225188
Enrollment
27
Registered
2020-05-11
Start date
2018-01-09
Completion date
Unknown
Last updated
2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Adult or pediatric XLH

Interventions

investigational material(s) Generic name etc : burosumab INN of investigational material : KRN23 Therapeutic category code : 399 Agents affecting metabolism, n.e.c. Dosage and Administration for Inves

Sponsors

Kyowa Kirin Co., Ltd.
Lead Sponsor

Eligibility

Sex/Gender
All

Inclusion criteria

Inclusion criteria: 1) Personally submitted voluntary written informed consent to participate in the study; For pediatric patients, personally submitted voluntary written informed consent by a legally authorized representative. If appropriate, written or verbal assent to participate in the study should be obtained from patients. 2) Patients meeting any of the followings; a) For adult XLH patients, completion the final observation at Week 96 in UX023-CL303 or UX023-CL304 b) For pediatric patients, completion the final observation at Week 64 in UX023-CL301 3) For female patients; women of childbearing potential (except for females who have not reached menarche, permanently sterilized, postmenopausal [12 months with no menses without an alternative medical cause] or anatomically not of childbearing potential) with negative pregnancy test at pre-treatment assessment of Week 0 4) For female patient with childbearing potential, or male patients with reproductive capacity; willingness to use acceptable methods of contraception while participating in the study 5) Willingness and ability to cooperatively complete all study procedures, adhere to the visit schedule and follow the investigator's instructions, as considered by investigator or subinvestigator

Exclusion criteria

Exclusion criteria: 1) Use of oral phosphate for treating XLH, pharmacologic vitamin D metabolites or analogs, aluminum hydroxide antacids, systemic corticosteroids, acetazolamide, and thiazides within 7 days prior to scheduled initial administration of investigational drug 2) Planned or recommended orthopedic surgery (implantation or removal), including staples, 8 plates or osteotomy, during the study period 3) Blood or blood product transfusion within 60 days prior to scheduled initial administration of investigational drug 4) Use of growth hormone therapy within 12 months prior to scheduled initial administration of investigational drug 5) Use of medication to suppress the secretion of parathyroid hormone (e.g., cinacalcet) within 60 days prior to scheduled initial administration of investigational drug 6) Use of any investigational product (except for investigational product of the preceding study) or investigational medical device within 4 months prior to scheduled initial administration of investigational drug, or requirement for any investigational agent prior to completion of all scheduled study assessments 7) Use of a therapeutic monoclonal antibody other than KRN23 within 90 days prior to scheduled initial administration of investigational drug 8) History of being positive for HIV antibody, HBs antigen and/or HCV antibody 9) Anyone otherwise considered unsuitable for the study by the investigator or subinvestigator

Design outcomes

Primary

MeasureTime frame
safety - Advere events - Laboratory data - Vital signs - 12-lead electrocardiogram (ECG) - Renal ultrasound - Echocardiogram (in subjects aged 5 years or older)

Secondary

MeasureTime frame
efficacy - Serum phosphorus, 1,25(OH)2D, urinary phosphorus, TRP, TmP/GFR, bone turnover markers - Motor functions - Radiographic findings - Serum phosphorus, 1,25(OH)2D, urinary phosphorus, TRP, TmP/GFR, ALP - Motor functions - RSS and RGI-C by radiography - Z score of height

Countries

Asia except Japan, Japan

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026