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Racial Differences in Phosphorus Metabolism

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ClinicalTrials.gov Identifier: NCT00856726
Recruitment Status : Completed
First Posted : March 6, 2009
Results First Posted : September 11, 2017
Last Update Posted : September 11, 2017
Information provided by (Responsible Party):

Study Description
Brief Summary:
The investigators aim to study potential racial differences in renal phosphorus handling by provocatively testing urinary phosphorus excretion using parathyroid hormone infusions in healthy white volunteers compared to healthy black volunteers.

Condition or disease Intervention/treatment
Control Drug: 1-34 parathyroid infusion

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 26 participants
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: Racial Differences in Phosphorus Metabolism
Study Start Date : February 2009
Primary Completion Date : June 2011
Study Completion Date : June 2011

Resource links provided by the National Library of Medicine

Drug Information available for: Phosphorus
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Experimental: PTH infusion
(1-34) PTH infusion at a rate of 0.055 ug/kg/hour for six hours
Drug: 1-34 parathyroid infusion
1-34 parathyroid infusion at 0.055 mcg/kg/hr for 6 hours

Outcome Measures

Primary Outcome Measures :
  1. Urinary Phosphorus Excretion [ Time Frame: six hours ]
    Fractional excretion of phosphorus (the fraction of phosphorus filtered by the kidney which is excreted in the urine)

Secondary Outcome Measures :
  1. Fibroblast Growth Factor 23 [ Time Frame: six hours ]
    The change in fibroblast growth factor 23 concentrations from baseline to six hours

  2. Serum Phosphorus [ Time Frame: six hours ]
    change in serum phosphorus from baseline to six hours

  3. Serum Calcium [ Time Frame: six hours ]
    change in serum calcium from baseline to six hours

  4. Parathyroid Hormone [ Time Frame: six hours ]
    change in parathyroid hormone from baseline to six hours

  5. Fractional Excretion of Calcium [ Time Frame: six hours ]
    change in urinary fractional excretion of calcium from baseline to six hours

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • 18 years of age or older
  • Body mass index (BMI) within 20% ideal for their age and gender

Exclusion Criteria:

  • Abnormal urinalysis
  • Pregnancy or breast-feeding
  • Medical conditions impacting phosphorus metabolism—primary hyperparathyroidism; diabetes mellitus; gastrointestinal malabsorption disorders; hyper- or hypothyroidism
  • Medications known to affect phosphorus metabolism— current use of phosphorus supplements, phosphorus binders, calcitriol or calcitriol analogues, regular antacid or laxative use, calcitonin, etidronate, anticonvulsants
  • Hyper- or hypophosphatemia (≥ 4.6 mg/dl or ≤ 2.5 mg/dl respectively), hyper- or hypocalcemia (≥ 10.6 or ≤ 8.5 mg/dl respectively), or severe anemia (Hgb < 8 g/dl for women and < 9 g/dl for men)
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00856726

United States, Florida
University of Miami
Miami, Florida, United States, 33136
Sponsors and Collaborators
University of Miami
National Institutes of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Principal Investigator: Orlando M Gutierrez, MD, MMSc University of Miami
More Information

Responsible Party: Orlando M. Gutierrez, MD, MMSc, Associate Professor, University of Alabama at Birmingham
ClinicalTrials.gov Identifier: NCT00856726     History of Changes
Other Study ID Numbers: 20080669
K23DK081673 ( U.S. NIH Grant/Contract )
First Posted: March 6, 2009    Key Record Dates
Results First Posted: September 11, 2017
Last Update Posted: September 11, 2017
Last Verified: September 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No