A Phase 4 interventional study of KRN23 in X-linked Hypophosphatemia (XLH), sponsored by Kyowa Kirin Co., Ltd.. Completed at 5 sites in China. Open to participants aged 1 Year to 12 Years. Per ClinicalTrials.gov, last updated 2024-07-09.
Sponsored by Kyowa Kirin Co., Ltd. · Phase 4, Interventional, and Treatment
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Among 18 studies testing burosumab in Familial Hypophosphatemic Rickets — none open to participants now, none under way, none of them phase 3. burosumab · Familial Hypophosphatemic Rickets.
Among the 18 studies testing burosumab in Familial Hypophosphatemic Rickets, this one is the 9th largest by enrollment, is one of 3 that started in 2021, is one of 4 in phase 4, and was the 17th registered.
49 studies on the registry are indexed under Familial Hypophosphatemic Rickets; 8 are open to participants now.
Browse Familial Hypophosphatemic Rickets studies →None of the 18 studies testing burosumab in Familial Hypophosphatemic Rickets is open now. The open studies under Familial Hypophosphatemic Rickets, anywhere →
burosumab: first FDA approval 2018 (CRYSVITA), first EMA approval 2018. What it is approved for, and how studies give it, is on its page →
Of the 4 Familial Hypophosphatemic Rickets studies recruiting now, 2 set no upper age limit and 2 stop at 75 or younger; 3 take children under 18; 1 takes healthy volunteers.
This study: 1 Year to 12 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
18 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 5 · Phase 2 6 · Phase 3 6 · Phase 4 4
First in 2008; this study’s year is marked. 3 started in 2021.
This study's enrollment of 28 is close to the median of 28 across 29 interventional studies indexed under Familial Hypophosphatemic Rickets.
Median enrollment 26 across the 18 interventional studies. Of the 17 that completed or were terminated, 9 (53%) have results posted.
This tab as a report to print or save as PDF → With an account.
15 of 18 have an industry lead sponsor. The 6 most frequent:
Kyowa Kirin Co., Ltd. is the lead sponsor of 159 studies on the registry; 8 are open to participants now.
21 studies in Familial Hypophosphatemic Rickets by Kyowa Kirin Co., Ltd.: 2 open now, 3 under way, none of them phase 3. Of 17 finished, 8 (47%) have results posted.
Among the 21 studies in Familial Hypophosphatemic Rickets by Kyowa Kirin Co., Ltd., this one is the 8th largest by enrollment of the 16 interventional ones that give a count, is one of 4 that started in 2021, is one of 2 in phase 4, and was the 18th registered.
Kyowa Kirin Co., Ltd.’s Familial Hypophosphatemic Rickets studies by the year they started, since 2008.
None of the studies under way reaches primary completion within a year.
Among the 18 studies testing burosumab in Familial Hypophosphatemic Rickets, from their registry updates:
Nothing recorded among them since 2026-09-25.
Among Kyowa Kirin Co., Ltd.’s 21 in Familial Hypophosphatemic Rickets:
This tab as a report to print or save as PDF → With an account.
The purpose of this study is to assess the safety, pharmacokinetics and efficacy of KRN23 in pediatric Chinese patients with XLH
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Diagnosis of XLH supported by either of the following:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
KRN23 0.8 mg/kg starting dose, administered Q2W by SC injection up to Week 64. Before KRN23 treatment, all patients will receive oral phosphate and vitamin D analogs for 12 weeks of Run-in period.
Drug: KRN23
KRN23 is a sterile clear colourless and preservative free solution supplied in single use 5 mL vials containing 1 mL of KRN23 at a concentration of 30mg/mL
Also known as: Burosumab, Crysvita
Change from Baseline (CFB) in mean serum phosphorus level at the end of the dose cycle
Time frame: Weeks 2, 4, 8, 12, 16, 24, 32, 40, 52, and 64
Change in rickets at Weeks 40 and 64 as examined by the Radiograph Global Impression of Change (RGI-C) global score
Changes in the severity of rickets and bowing were assessed using a disease specific qualitative RGI-C scoring system. The RGI-C is a 7-point ordinal scale with possible values: +3 = very much better (complete or near complete healing of rickets), +2 = much better (substantial healing of rickets), +1 = minimally better (i.e., minimal healing of rickets), 0 = unchanged, -1 = minimally worse (minimal worsening of rickets), -2 = much worse (moderate worsening of rickets), -3 = very much worse (severe worsening of rickets).
Time frame: Weeks 40 and 64
Change in Rickets Severity Score (RSS) total score at Weeks 40 and 64
The RSS system is a 10-point radiographic scoring method that was developed to assess the severity of nutritional rickets in the wrists and knees based on the degree of metaphyseal fraying, cupping, lucency, separation, and the proportion of the growth plate affected. Scores are assigned for the unilateral wrist and knee X-rays deemed by the rater to be the more severe of the bilateral images. The maximum total score on the RSS is 10 points and the minimum score is 0, with a total possible score of 4 points for the wrists and 6 points for the knees (the total score is the sum of the wrist and knee score). Higher scores indicate greater rickets severity.
Time frame: Weeks 40 and 64
Change in lower extremity skeletal abnormalities, including genu varum and genu valgus, as determined by the RGI-C long leg score at Weeks 40 and 64
Changes in the severity of lower extremity skeletal abnormalities, including genu varum and genu valgus, were assessed using a disease specific qualitative RGI-C scoring system. The RGI-C is a 7-point ordinal scale with possible values: +3 = very much better (complete or near complete healing), +2 = much better (substantial healing), +1 = minimally better (i.e., minimal healing), 0 = unchanged, -1 = minimally worse (minimal worsening), -2 = much worse (moderate worsening), -3 = very much worse (severe worsening).
Time frame: Weeks 40 and 64
Change in serum phosphorus over time
Time frame: Weeks 0, 1, 2, 4, 8, 12, 16, 24, 32, 40, 52, 64, and 74
Change in serum 1,25-dihydroxyvitamin D (1,25(OH)2D) over time
Time frame: Weeks 0, 1, 2, 4, 8, 12, 16, 24, 32, 40, 52, 64, and 74
Change in alkaline phosphatase (ALP) over time
Time frame: Weeks 0, 1, 2, 4, 8, 12, 16, 24, 32, 40, 52, 64, and 74
Change in urinary phosphorus over time
Time frame: Weeks 0, 1, 2, 4, 8, 12, 16, 24, 32, 40, 52, 64, and 74
Change in ratio of renal tubular maximum reabsorption rate of phosphate to glomerular filtration rate (TmP/GFR; algorithm method) over time
Time frame: Weeks 0, 1, 2, 4, 8, 12, 16, 24, 32, 40, 52, 64, and 74
Change in recumbent length/standing height in cm, height for age z scores
Time frame: Weeks 0, 24, 40 and 64
Change in growth velocity from pre-treatment and post-treatment over time
Time frame: Weeks 0, 24, 40 and 64
Change in growth velocity z scores from pre-treatment and post-treatment over time
Time frame: Weeks 0, 24, 40 and 64
Six-minute walking test (6MWT) results to examine walking ability (total distance; patients ≥5 years at the time of signing the ICF only)
Time frame: Weeks 0, 24, 40 and 64
Six-minute walking test (6MWT) results to examine walking ability (percent of predicted normal; patients ≥5 years at the time of signing the ICF only)
Time frame: Weeks 0, 24, 40 and 64
Ten-item Short Form Health Survey for Children (SF-10) physical domain scores to examine health-related Quality of Life
The SF-10 is a brief, 10-item, guardian-completed assessment designed to measure the physical and psychosocial functioning of children. The physical functioning (PHS) domain includes 5 questions that assess limitations in physical activities because of health problems. The PHS domain score was calculated using norm-based scoring so that 50 is the average score and the standard deviation equals 10. Higher scores are associated with better functioning/quality of life; a positive change from Baseline score indicates an improvement.
Time frame: Weeks 0, 24, 40 and 64
Ten-item Short Form Health Survey for Children (SF-10) Psychosocial scores to examine health-related Quality of Life
The SF-10 is a brief, 10-item, guardian-completed assessment designed to measure the physical and psychosocial functioning of children. The Psychosocial functioning (PSS) domain includes 5 questions that assess limitations in psychosocial activities because of health problems. The PHS domain score was calculated using norm-based scoring so that 50 is the average score and the standard deviation equals 10. Higher scores are associated with better functioning/quality of life; a positive change from Baseline score indicates an improvement.
Time frame: Weeks 0, 24, 40 and 64
Face Pain Scale-Revised (FPS-R) scores to examine health-related Quality of Life
The FPS-R is a dimensionless 10 point Likert scale used to assess self-reported pain intensity on a scale from 0 (no pain) to 10 (most pain you can imagine). Greater pain scores are indicative of more severe pain.
Time frame: Weeks 0, 24, 40 and 64
Patient-Reported Outcomes Measurement Information System (PROMIS) scores to examine health-related Quality of Life
The PROMIS was developed by the National Institutes of Health and uses domain-specific measures to assess patient well-being (Broderick et al. 2013), (NIH 2015). It uses a T-score metric in which 50 is the mean of a relevant reference population and 10 is the standard deviation (SD) of that population. For the Pain Interference Domain, decreases indicate less pain, for the Physical Function Mobility Domain, increases indicate greater mobility and for the Fatigue Domain, decreases indicate less fatigue.
Time frame: Weeks 0, 24, 40 and 64
Safety of KRN23 by studying the number, severity and relatedness of Adverse Events (including laboratory and imaging assessments)
Incidence, frequency, and severity of AEs and SAEs, including clinically significant changes in laboratory assessments as well as ECHO, ECG, ultrasound, vital sign, X-Ray images and Anti-KRN23 antibody.
Time frame: Week 0 to Week 76
Pharmacokinetics (PK): KRN23 concentrations
Time frame: Weeks 0, 1, 2, 4, 8, 16, 24, 40, 64, and 74
Change from Week -14 to Baseline in serum phosphorus over time during Run-in Period
Time frame: Week -14, -10 and -4
Change from Week -14 to Baseline in serum 1,25(OH)2D over time during Run-in Period
Time frame: Week -14, -10 and -4
Change from Week -14 to Baseline in plasma iPTH over time during Run-in Period
Time frame: Week -14, -10 and -4
Change from Week -14 to Baseline in serum calcium over time during Run-in Period
Time frame: Week -14, -10 and -4
Change from Week -14 to Baseline in urinary phosphorus over time during Run-in Period
Time frame: Week -14, -10 and -4
Change from Week -14 to Baseline in TmP/GFR (algorithm method) over time during Run-in Period
Time frame: Week -14, -10 and -4
Safety of conventional therapy by studying the number, severity and relatedness of Adverse Events
Incidence, frequency, and severity of AEs and SAEs, including clinically significant changes in laboratory assessments during Run-in period
Time frame: Week -14 to Week 0
Plan to share: No
No publications or documents are linked to this record.
Ran from Nov 2021 to primary completion in Dec 2023, 25 months.
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This study is completed, as verified in Jul 2024. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Burosumab
Familial Hypophosphatemic Rickets →