Status:
COMPLETED
Improving the Understanding of the Response to Vitamin D Supplementation
Lead Sponsor:
University of Wisconsin, Madison
Collaborating Sponsors:
Merck Sharp & Dohme LLC
Conditions:
Vitamin D Deficiency
Eligibility:
FEMALE
50-100 years
Phase:
PHASE3
Brief Summary
It is the investigators hypothesis that the current method of evaluating vitamin D status, measuring circulating 25-hydroxy vitamin D is not providing the full metabolic picture, and is therefore inad...
Detailed Description
This hypothesis is supported by several observations. First, recent work finds previously unappreciated vitamin D metabolites, notably 3 epi-25(OH)D348 and sulfated 25(OH)D3, in virtually all human se...
Eligibility Criteria
Inclusion
- Healthy, community-dwelling ambulatory postmenopausal White, non-Hispanic women
- Able and willing to sign informed consent
- Baseline serum 25(OH)D concentration of 10-29 ng/mL
- Willing to not alter the amount of their baseline vitamin D supplementation during the course of this study
- Willing to use sunscreen (SPF ≥15) when sun exposure of \> 15 minutes is expected
Exclusion
- Presence of any measurable circulating 25(OH)D2 on screening measurement
- Current hypercalcemia (serum calcium \> 10.5 mg/dl) or untreated primary hyperparathyroidism
- History of nephrolithiasis
- Known risk factors for hypercalcemia, e.g., malignancy, tuberculosis, sarcoidosis
- History of any form of cancer within the past five years with the exception of adequately treated squamous cell or basal cell skin carcinoma
- Renal failure; defined as a calculated creatinine clearance (using the Cockroft-Gault approach) of ≤ 35 ml/minute
- Severe end-organ disease, e.g., cardiovascular, hepatic, hematologic, pulmonary, etc., which might limit the ability to complete this study
- Known metabolic bone disease, e.g., Paget's disease, osteomalacia
- Treatment with any drug known to interfere with vitamin D metabolism, e.g., phenytoin, phenobarbital
- Treatment with high dose vitamin D (≥ 50,000 IU weekly) or any active metabolites of vitamin D, e.g., calcitriol, within six months of screening
- Use of tanning beds or salons or unwillingness to utilize sunscreen during periods of sun exposure of 15 minutes or longer
- Planned trips/vacations likely to be associated with substantial amounts of sun exposure during the course of the study
Key Trial Info
Start Date :
December 1 2011
Trial Type :
INTERVENTIONAL
Allocation :
ACTUAL
End Date :
December 1 2014
Estimated Enrollment :
62 Patients enrolled
Trial Details
Trial ID
NCT01465178
Start Date
December 1 2011
End Date
December 1 2014
Last Update
November 25 2016
Active Locations (1)
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1
University of Wisconsin
Madison, Wisconsin, United States, 53705