Magnitude of Changes in 25 OH Vitamin D3 Levels After Vitamin D3 Supplementation

Phase 1

Withdrawn

• Conditions: Vitamin D Deficiency
• Interventions: Drug: Placebo orally daily for 5 months; Drug: vitamin D3 1000 IU orally daily for 5 months; Drug: vitamin D3 3000 IU orally daily for 5 months; Drug: vitamin D3 5000 IU orally daily for 5 months

• Registration Number: NCT01170507
• Lead Sponsor: King Faisal Specialist Hospital & Research Center

Brief Summary

Vitamin D deficiency is common world wide. 25 OH vitamin D level is the best indicator of vitamin D status. The determination of the appropriate dose of vitamin D supplement is essential for management of vitamin D deficiency as well as for designing vitamin D fortification programs. The increments in 25 OH vitamin D levels following various doses of vitamin D supplement for different genders, body weights, and starting 25 OH vitamin D level have not been well defined. The time course of depletion of repleted vitamin D stores is also not known.

The investigators plan to conduct a double blind randomized study on 9 cohorts to determine levels of 25 OH vitamin D following supplementation with different doses of vitamin D3 for 5 months and their withdrawal for 3 months.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2010-07-25
• Study First Submitted QC: 2010-07-26
• Study First Posted: 2010-07-27
• Study Start: 2011-12
• Primary Completion: 2016-08
• Study Completion: 2016-08
• Status Verified: 2018-03
• Last Update Submitted: 2018-03-06
• Last Update Posted: 2018-03-07

Recruitment & Eligibility

• Status: WITHDRAWN
• Sex: All
• Target Recruitment: Not specified

Inclusion Criteria

• Adults living in Riyadh area who consume no more than one serving of milk/day, do not take vitamin supplement, habitually have less than 10 hr of sun exposure per week, don't suffer from granulomatous conditions, liver disease, or kidney disease, and don't take anticonvulsants, barbiturates, or steroids.
• Individuals with with total 25 OH vitamin D level exceeding 100 nmol/l will be excluded from the study. Individuals with 25 OH vitamin D levels less than 20 nmol/L will be excluded from the placebo arm.

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo orally daily for 5 months	-
vitamin D3 1000 IU	vitamin D3 1000 IU orally daily for 5 months	-
Vitamin D3 3000 IU	vitamin D3 3000 IU orally daily for 5 months	-
Vitamin D3 5000 IU	vitamin D3 5000 IU orally daily for 5 months	-

Primary Outcome Measures

Name	Time	Method
Slope of 25 OH vitamin D3 level vs vitamin D3 dose	5 months	The primary endpoint is the slope of the dose (vitamin D3)- response (25 OH vitamin D3 level) curve for each cohort. The slope of the placebo group will be used to determine changes in 25 OH vitamin D3 levels that are not related to study intervention. The slope will be determined over 5 months.

Secondary Outcome Measures

Name	Time	Method
slope of vitamin D3 level vs vitamin D3 dose	5 months	slope of vitamin D3 level vs vitamin D3 dose over 5 months
incidence of hypercalcemia	8 months	incidence of hypercalcemia over 8 months
incidence of hypercalciuria	8 months	incidence of hypercalciuria over 8 months
slope of decline of 25 OH vitamin D3 level vs time	3 months	slope of decline of 25 OH vitamin D3 level vs time over 3 months

Trial Locations

Locations (1)

King Faisal Specialist Hospital & Research Center; 🇸🇦 Riyadh, Saudi Arabia