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Suspected Deficient Activation of Vitamin D in Patients With Secondary Hyperparathyroidism (1hydroxylase)

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ClinicalTrials.gov Identifier: NCT00754442
Recruitment Status : Completed
First Posted : September 18, 2008
Results First Posted : May 14, 2014
Last Update Posted : May 17, 2017
Sponsor:
Information provided by (Responsible Party):

Study Description
Brief Summary:
The purpose of this study is to determine if a reduction in the enzyme 1-hydroxylase, which activates Vitamin D, is the cause of overactivity of the parathyroid glands (called secondary hyperparathyroidism - normal blood calcium and elevated parathyroid hormone) in a selected group of young patients with normal kidney function.

Condition or disease Intervention/treatment
Secondary Hyperparathyroidism Drug: Teriparatide

Detailed Description:
Vitamin D, an essential nutrient, is produced by the skin after sunlight shines on it. Vitamin D must then be activated by both the liver and the kidneys to perform its function of maintaining strong bones and helping to prevent heart disease, infection, diabetes and cancer. Reduced kidney activation of Vitamin D occurs with advanced age and with all kidney diseases. We have identified a small group of patients who appear to have reduced ability of the kidneys to activate vitamin D, even though they are young and do not have chronic kidney disease. In these patients, we are comparing the ability of their kidneys to activate Vitamin D to that of healthy controls. To stimulate the kidneys to activate Vitamin D, we are giving parathyroid hormone intravenously over 8 hours and collecting blood and urine at baseline, 4 and 8 hours. This type of parathyroid infusion does not cause side effects. The gene that controls this activation is also being studied (by a simple blood test) to look for abnormalities. We are now actively recruiting healthy controls for this study.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 20 participants
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: Clinical and Molecular Characterization of Suspected Partial 25-hydroxyvitamin D-1-alpha-hydroxylase Deficiency
Study Start Date : February 2007
Primary Completion Date : August 2008
Study Completion Date : August 2008

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Vitamin D
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Active Comparator: teriparatide control
control subject
Drug: Teriparatide
Teriparatide will be given by continuous intravenous infusion at a rate of 12 pmol/kg/hr for 8 hours to both "patients" and "controls"
Other Name: Forteo
Experimental: Teriparatide Patient
Patient with secondary hyperparathyroidism
Drug: Teriparatide
Teriparatide will be given by continuous intravenous infusion at a rate of 12 pmol/kg/hr for 8 hours to both "patients" and "controls"
Other Name: Forteo


Outcome Measures

Primary Outcome Measures :
  1. The Level of Activated Vitamin D (1,25-dihydroxyvitamin D) After Parathyroid Hormone Infusion at Baseline, 4 and 8 Hours [ Time Frame: baseline, 4 and 8 hours after start of infusion ]
    1,25-D was measured at baseline, 4 and 8 hours after PTH infusion


Secondary Outcome Measures :
  1. The Number of Patients With Mutations in CYP27B1 [ Time Frame: blood samples taken at baseline and sequenced over several days ]
    CYP27B1 gene (the gene for 25-hydroxyvitamin D-1-alpha hydroxylase) was sequenced for all in patient group and compared with published control data


Eligibility Criteria

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Ages Eligible for Study:   40 Years to 59 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Caucasian female
  • Age 40-59 years
  • Serum creatinine < 1.3 and estimated glomerular filtration rate (GRF) > 60
  • Serum calcium in the normal range (for U Md lab 8.6-10 mg/dl)
  • Parathyroid hormone in the normal range (for U Md lab 12-54 pg/ml)
  • Normal 25-hydroxyvitamin D level (30 ng/ml or higher)
  • For women of childbearing age, non-pregnant (based on negative urine pregnancy test on the morning of the teriparatide infusion)

Exclusion Criteria:

  • Non-caucasian
  • Age under 40 and over 59 years
  • Male
  • Serum creatinine over 1.3 or estimated glomerular filtration rate (GFR) < 60
  • Abnormal serum calcium (for U Md lab, below 8.6 or above 10 mg/dl)
  • Abnormal parathyroid hormone (for U Md lab, above 65 or below 12 pg/ml)
  • For women of childbearing age, non-pregnant (based on urine pregnancy test on the morning of the teriparatide infusion)
  • History of bone radiation
  • History of Paget disease of bone
  • History of bone malignancy or metastases
  • History of allergy or sensitivity to Forteo
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): NCT00754442


Locations
United States, Maryland
University of Maryland School of Medicine Division of Endocrinology
Baltimore, Maryland, United States, 21201
Sponsors and Collaborators
University of Maryland
Investigators
Principal Investigator: Elizabeth A Streeten, MD Division of Endocrinology, University of Maryland School of Medicine
More Information

Publications:
Responsible Party: Elizabeth Streeten, Associate Professor of Medicine, University of Maryland
ClinicalTrials.gov Identifier: NCT00754442     History of Changes
Other Study ID Numbers: H-28679
H-28679 ( Other Identifier: IRB number )
First Posted: September 18, 2008    Key Record Dates
Results First Posted: May 14, 2014
Last Update Posted: May 17, 2017
Last Verified: April 2017

Keywords provided by Elizabeth Streeten, University of Maryland:
hyperparathyroidism
parathyroid
vitamin D
vitamin D deficiency

Additional relevant MeSH terms:
Neoplasm Metastasis
Hyperparathyroidism
Hyperparathyroidism, Secondary
Neoplastic Processes
Neoplasms
Pathologic Processes
Parathyroid Diseases
Endocrine System Diseases
Vitamins
Vitamin D
Ergocalciferols
Teriparatide
Micronutrients
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents