Phase 4
N=10
Examining the Effect of Burosumab on Muscle Function
X-linked Hypophosphatemia
Bottom Line
View on ClinicalTrials.gov: NCT04146935 ↗Enrolled (actual)
10
Serious AEs
10.0%
Results posted
Aug 2023
Primary outcome: Primary: Skeletal Muscle Adenosine Triphosphate (ATP) Synthesis Rate — 9.41 umol/g/min — p=0.4147
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 4
- Interventions
- Burosumab Injection [Crysvita] (Drug)
- Age
- Adult, Older Adult · 18+ yrs
- Sex
- All
- Sponsor
- Yale University
- Primary completion
- Aug 2022
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Skeletal Muscle Adenosine Triphosphate (ATP) Synthesis Rate |
9.41 | 0.4147 |
| SECONDARY Serum Phosphate |
2.85 | <.0001 sig |
| SECONDARY Intracellular Phosphate Concentration in Umol/g Muscle |
2.31 | 0.6957 |
Summary
Patients with X-linked hypophosphatemia (XLH) often report symptoms of fatigue and weakness particularly after exertion, in addition to their skeletal complaints. In previous trials using KRN23 (same drug as burosumab/Crysvita®), patients report these symptoms improve. The investigators wish to test this hypothesis directly by measuring muscle energy when patients begin treatment with Crysvita® for the first time.
Eligibility Criteria
Inclusion Criteria
- 18-65 years of age
- Diagnosis of XLH
- eGFR ≥ 50 (estimated glomerular filtration rate)
- Normal serum calcium
- Phosphate ≤ 2.5 mg/dl
- Deemed clinically appropriate for starting therapy with Burosumab/Crysvita® (based on the treating physician's evaluation)
- Deemed appropriate for MR Spectroscopy
Exclusion Criteria
- Patients with fixed skeletal abnormalities which would prevent them from successfully completing study-related functional assessments
- Patients unwilling to stop therapy with supplemental phosphate and calcitriol 2 weeks prior to enrollment.
- Patients who have undergone an orthopaedic procedure within the previous 6 months involving implantation of metal hardware
Data sourced from ClinicalTrials.gov (NCT04146935). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.