Studying Phosphorus Metabolism
|First Received Date ICMJE||August 4, 2003|
|Last Updated Date||March 3, 2008|
|Start Date ICMJE||August 2003|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00066183 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Studying Phosphorus Metabolism|
|Official Title ICMJE||Studies in Phosphorus Metabolism|
Phosphorus and phosphate irons play critical roles in bone structure and essential cellular functions.
The purpose of this study is to learn more about the factors and hormones that regulate phosphorus in the body by collecting blood and urine samples from patients with disorders of phosphate control.
Both children and adults will be enrolled in this study. Researchers will collect blood and urine samples from participants on multiple occasions (2 to 6 times). Some blood specimens will be taken after an overnight fast and participants may be asked to collect all their urine during a 24-hour period. Researchers will analyze these blood and urine samples to better understanding how the body handles phosphorus.
Phosphorus and phosphate ions play an important role in cellular metabolism as well as bone structure. Scientific evidence suggests that, in addition to Vitamin D and PTH systems, novel factors, such as Fibroblast Growth Factor 23 (FGF-23) and Matrix extracellular phosphoglycoprotein (MEPE), may play an important role in phosphorus regulation. These factors have been best studied in rare genetic and acquired phosphate wasting disorders such as tumor induced osteomalacia (TIO), X linked hypophosphatemia (XLH) and autosomal dominant hypophosphatemic rickets (ADHR). Patients with other abnormal phosphate regulating states such as hyperparathyroidism and hypoparathyroidism, pseudohypoparathyroidism etc. undergoing phosphorus-altering interventions may provide important insight into the role of these hormones.
We are proposing an observational study with collection of blood and urine samples to study both established (e.g. mineral ions, bone markers, PTH-Vit D system, TMP-GFR) and novel (e.g. FGF-23 and MEPE) constituents of the phosphorus metabolism pathway. Patients with abnormal phosphorus regulating states will be enrolled and we will study the natural history of their disease and the effects of specific interventions that are likely to change phosphorus balance.
The outcome will potentially aid understanding of this new field of mineral regulating hormones and generate both interest and research in phosphorus metabolism. It is hoped that this will also encourage clinical trials in treatment of phosphate wasting disorders.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Condition ICMJE||Phosphorus Metabolism|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Completion Date||January 2005|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Patients of any age, gender or ethnicity who will help fulfill the objectives laid out in Section II.
We propose to study patients primarily enrolled in other clinical center protocol(s). They will continue to receive treatment/ interventions per the original protocols.
Patients with significant cognitive impairment who are unable to give informed consent or patients having other significant mineral disturbances that could confound the parameters being studied will be excluded.
|Accepts Healthy Volunteers||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries ICMJE||United States|
|Removed Location Countries|
|NCT Number ICMJE||NCT00066183|
|Other Study ID Numbers ICMJE||030254, 03-D-0254|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Institute of Dental and Craniofacial Research (NIDCR)|
|Collaborators ICMJE||Not Provided|
|Investigators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||January 2005|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP