Burosumab for CSHS (NCT03993821) | Clinical Trial Compass
UnknownEarly Phase 1
Burosumab for CSHS
United States1 participantsStarted 2019-07-01
Plain-language summary
Burosumab (also known as the drug, Crysvita®) is a fully human immunoglobulin G1 (IgG1) monoclonal antibody (mAb) that binds to and inhibits the activity of fibroblast growth factor 23 (FGF23), leading to an increase in serum phosphorus levels. This drug is already approved for use in patients with X-linked hypophosphatemia (XLH), but not for Cutaneous Skeletal Hypophosphatemia Syndrome (CSHS). It is hypothesized that burosumab may provide clinical benefit to a patient with CSHS due to the common underlying feature in this patient and in patients with XLH - abnormally elevated FGF23 in the context of low age -adjusted serum phosphorous levels.
Who can participate
Sex
ALL
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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Patient has confirmed CSHS by physician diagnosis
. Patient has confirmed FGF23 elevations in the context of a low fasting serum phosphorous \< 2.5 mg/dL
. Patient able to tolerate burosumab treatment
. Have a corrected serum calcium level \< 10.8 mg/dL
. Have an eGFR \>25 mL/min/1.73m2 (using CKD-EPI equation)
. Must be willing in the opinion of the investigators, to comply with study procedures and schedule
. Provide written informed consent by the subject or a Legal Authorized Representative (LAR) after the study has been explained and prior to any research related procedures begin
. Must have a negative pregnancy test at Screening and be willing to have additional pregnancy tests during the study.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
. Concomitant use of active vitamin D (i.e. calcitriol) and/or exogenous phosphate supplementation during burosumab therapy. Subjects will be allowed over the counter Vitamin D should levels drop below \<20 ng/ml
. Blood phosphorus level within or above the normal range while not taking phosphate or active Vitamin D.
. Severe renal impairment or end-stage renal disease, defined as an eGFR of less than 25 ml/min/1.73m2
. The use or enrollment in studies using other investigational therapies including other monoclonal antibodies
. Subject or Legally Authorized Representative not willing or not able to give written informed consent
. In the investigator's opinion, the subject may not be able to meet all the requirements for study participation
. History of hypersensitivity to burosumab excipients that in the opinion of the investigator, places the subject at an increased risk of adverse effects
. Subject has a condition that in the opinion of the investigator could present a concern for subject safety or data interpretation.