Autosomal Dominant Hypophosphatemic Rickets Clinical Trial
Official title:
Iron Therapy for Autosomal Dominant Hypophosphatemic Rickets: A Pilot
| NCT number | NCT02233322 |
| Other study ID # | IRON/ADHR |
| Secondary ID | |
| Status | Completed |
| Phase | N/A |
| First received | |
| Last updated | |
| Start date | August 2014 |
| Est. completion date | November 12, 2019 |
| Verified date | November 2019 |
| Source | Indiana University |
| Contact | n/a |
| Is FDA regulated | No |
| Health authority | |
| Study type | Interventional |
The purpose of the study is to gain a better understanding of the effect of iron on fibroblast growth factor 23 (FGF23) in the inherited disorder, autosomal dominant hypophosphatemic rickets (ADHR). ADHR is an inherited disorder in which the body makes too much FGF 23 and causes low blood phosphorus levels and bone problems such as rickets (bowed legs in children) or bone pain and weakness in adults. This study is to test whether or not giving iron helps correct the high FGF23 and there by correcting the phosphate problem.
| Status | Completed |
| Enrollment | 8 |
| Est. completion date | November 12, 2019 |
| Est. primary completion date | November 12, 2019 |
| Accepts healthy volunteers | No |
| Gender | All |
| Age group | 25 Months and older |
| Eligibility |
Inclusion Criteria: - FGF Mutation in either Arginine 176 or arginine 179 - able and willing to provide consent or have a parent that is able/willing to consent, if a minor - either serum iron <50mcg/dl (regardless of phosphate or intact FGF23 concentration); or iron between 500 and 100mcg/dl with serum phosphorus value below 3.0mg/dl for adults or less than or equal to 0.5 mg/dl the lower limit of normal for age in children and intact FGF23 about 30pg/ml - age >2 years - May be receiving treatment with phosphate and calcitriol, but must be willing to undergo dose adjustments by the investigators if iron resolves the phosphate wasting defect. Exclusion Criteria: - malignancy within the last 5 years, except treated squamous or basal cell skin carcinoma - terminal illness/hospice. - severe end-organ disease, e.g. cardiovascular, pulmonary, etc, which may limit ability to complete study. estimated GFR <45ml/min/1.73m2, calculated using MDRD formula for adults or modified Schwartz equation for children - pregnancy or plan on becoming pregnant |
| Country | Name | City | State |
|---|---|---|---|
| United States | Indiana University School of Medicine | Indianapolis | Indiana |
| Lead Sponsor | Collaborator |
|---|---|
| Indiana University |
United States,
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* Note: There are 18 references in all — Click here to view all references
| Type | Measure | Description | Time frame | Safety issue |
|---|---|---|---|---|
| Primary | Does increasing serum iron concentrations above 100 mcg/dl in patients with ADHR result in a decrease in intact FGF23. | Perform a pilot study in ADHR patients with low serum iron concentrations (defined below) to determine if increasing serum iron concentrations above 100 mcg/dl results in a decrease in intact FGF23 (primary endpoint) and C-terminal FGF23 concentrations by at least 20% and normalizes serum phosphorus and TMP/GFR (tubular maximum phosphate reabsorption/ glomerular filtration rate) within 6 months of attaining goal iron concentrations. | FGF23 will be measured at 1, 2, 3, 6, 9, and 12 months |