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Showing 25–48 of 243 matching trials from the live ClinicalTrials.gov search.
Conditions
Human Immunodeficiency Virus (HIV), Vitamin D Deficiency, HIV Infections
Interventions
Vitamin D, Placebo
Drug · Other
Lead sponsor
University Hospitals Cleveland Medical Center
Other
Eligibility
18 Years and older
Enrollment
45 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010
U.S. locations
1
States / cities
Cleveland, Ohio
Conditions
Hypocalcemia, Pseudohypoparathyroidism, Osteomalacia, Rickets, Pseudopseudohpoparathyroidism
Interventions
Not listed
Lead sponsor
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
NIH
Eligibility
2 Months to 100 Years
Enrollment
70 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
1997 – 2022
U.S. locations
1
States / cities
Bethesda, Maryland
Conditions
Chronic Kidney Disease
Interventions
Not listed
Lead sponsor
Saint Louis VA Medical Center
Federal
Eligibility
18 Years to 80 Years
Healthy volunteers
Healthy volunteers not accepted
U.S. locations
1
States / cities
St Louis, Missouri
Conditions
Deficiency of Vitamin D3, COPD
Interventions
Cholecalciferol, multivitamin, Placebo
Dietary Supplement
Lead sponsor
University of Pittsburgh
Other
Eligibility
50 Years to 85 Years
Enrollment
10 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2018
U.S. locations
1
States / cities
Pittsburgh, Pennsylvania
Conditions
Chronic Kidney Disease, Hyperparathyroidism, Secondary, Vitamin D Deficiency
Interventions
CTAP101 30 μg capsules, Sugar pill to CTAP101 30 μg capsules
Drug · Other
Lead sponsor
OPKO IP Holdings II, Inc.
Industry
Eligibility
18 Years and older
Enrollment
213 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2014
U.S. locations
1
States / cities
Bannockburn, Illinois
Conditions
HIV Infection
Interventions
Vitamin D3 50,000 IU, Vitamin D3 placebo
Dietary Supplement
Lead sponsor
University of North Carolina, Chapel Hill
Other
Eligibility
16 Years to 24 Years
Enrollment
214 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2016
U.S. locations
16
States / cities
Los Angeles, California • Washington D.C., District of Columbia • Fort Lauderdale, Florida + 11 more
Conditions
Polycystic Ovary Syndrome, Vitamin D Deficiency
Interventions
Vitamin D3
Drug
Lead sponsor
Maimonides Medical Center
Other
Eligibility
16 Years to 48 Years · Female only
Enrollment
79 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2013
U.S. locations
1
States / cities
Brooklyn, New York
Completed Not applicable Interventional Accepts healthy volunteers Results available

Suspected Deficient Activation of Vitamin D in Patients With Secondary Hyperparathyroidism

NCT00754442
Conditions
Secondary Hyperparathyroidism
Interventions
Teriparatide
Drug
Lead sponsor
University of Maryland, Baltimore
Other
Eligibility
40 Years to 59 Years · Female only
Enrollment
20 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2007 – 2008
U.S. locations
1
States / cities
Baltimore, Maryland
Recruiting Not applicable Interventional Accepts healthy volunteers

Evaluating Response to Vitamin D3 and K2 Supplementation in Healthcare Personnel

NCT07199829
Conditions
Hypovitaminosis D, Hypovitaminosis
Interventions
Vitamin Arm 1, Vitamin Arm 2, Vitamin Arm 3, Placebo
Dietary Supplement · Other
Lead sponsor
Madigan Army Medical Center
Federal
Eligibility
18 Years to 69 Years
Enrollment
96 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
Tacoma, Washington
Completed Not applicable Interventional Results available

Vitamin D Supplementation in Psychiatric Illnesses

NCT01004354
Conditions
Obesity, Vitamin D Deficiency, Psychosis, Schizophrenia, Schizoaffective Disorder
Interventions
Ergocalciferols
Drug
Lead sponsor
University of Massachusetts, Worcester
Other
Eligibility
10 Years to 18 Years
Enrollment
12 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2010
U.S. locations
1
States / cities
Worcester, Massachusetts
Conditions
Secondary Hyperparathyroidism Due to Renal Causes, Chronic Kidney Diseases, Vitamin D Deficiency, Stage 5 Chronic Kidney Disease
Interventions
Calcifediol Oral Capsule, Placebo oral capsule
Drug
Lead sponsor
OPKO Health, Inc.
Industry
Eligibility
18 Years and older
Enrollment
44 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2021
U.S. locations
18
States / cities
Peoria, Arizona • Phoenix, Arizona • Cypress, California + 13 more
Withdrawn Not applicable Interventional Accepts healthy volunteers

Vitamin D and Blood Pressure

NCT00459563
Conditions
Hypertension
Interventions
Vitamin D, calcitriol, Placebo
Drug
Lead sponsor
Atlanta VA Medical Center
Federal
Eligibility
18 Years to 80 Years
Healthy volunteers
Accepts healthy volunteers
Timeline
2007 – 2011
U.S. locations
1
States / cities
Decatur, Georgia
Conditions
Secondary Hyperparathyroidism, Chronic Kidney Disease
Interventions
Paricalcitol, Ergocalciferol
Drug
Lead sponsor
Salem Veterans Affairs Medical Center
Federal
Eligibility
18 Years and older
Enrollment
80 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2011
U.S. locations
1
States / cities
Salem, Virginia
Conditions
Hyperphosphatemia
Interventions
Niacinamide, Placebo
Drug
Lead sponsor
Washington University School of Medicine
Other
Eligibility
18 Years and older
Enrollment
17 participants
Timeline
2006 – 2007
U.S. locations
1
States / cities
St Louis, Missouri
Completed Not applicable Interventional Accepts healthy volunteers

Different Vitamin D Preparations & FGF23 in Humans

NCT00957879
Conditions
Vitamin D Deficiency
Interventions
Ergocalciferol, Calcitriol
Dietary Supplement
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years to 45 Years
Enrollment
42 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2011
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Hypophosphatasia
Interventions
asfotase alfa
Drug
Lead sponsor
Alexion Pharmaceuticals, Inc.
Industry
Eligibility
13 Years to 65 Years
Enrollment
19 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2016
U.S. locations
2
States / cities
St Louis, Missouri • Durham, North Carolina
Conditions
Urinary Incontinence, Vitamin D Deficiency
Interventions
Vitamin D3 50,000 IU, Placebo
Dietary Supplement · Other
Lead sponsor
University of Alabama at Birmingham
Other
Eligibility
50 Years and older · Female only
Enrollment
243 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2017
U.S. locations
1
States / cities
Birmingham, Alabama
Conditions
Vitamin D Deficiency, Rotator Cuff Tears
Interventions
Vitamin D3 supplementation, Placebo
Dietary Supplement · Other
Lead sponsor
Community Memorial Health System
Other
Eligibility
18 Years to 65 Years
Enrollment
240 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2021 – 2024
U.S. locations
2
States / cities
Ventura, California
Completed Not applicable Interventional Accepts healthy volunteers

Availability of Vitamin D in Orange Juice

NCT01778114
Conditions
Vitamin D Deficiency
Interventions
Vitamin D2 in orange juice, Vitamin D3 in orange juice, Vitamin D2, Vitamin D3, Placebo
Dietary Supplement · Other
Lead sponsor
Boston University
Other
Eligibility
18 Years and older
Enrollment
86 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2006 – 2007
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
HIV Infection, Bone Mass
Interventions
cholecalciferol plus calcium carbonate
Dietary Supplement
Lead sponsor
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
NIH
Eligibility
6 Years to 16 Years
Enrollment
59 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2003 – 2006
U.S. locations
1
States / cities
New York, New York
Conditions
Renal Osteodystrophy
Interventions
doxercalciferol, Cholecalciferol
Drug
Lead sponsor
Indiana University
Other
Eligibility
18 Years to 82 Years
Enrollment
55 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2006 – 2009
U.S. locations
1
States / cities
Indianapolis, Indiana
Completed Not applicable Interventional Results available

Vitamin D Repletion in Coronary Artery Disease

NCT01570309
Conditions
Vitamin D Deficiency, Coronary Artery Disease, Endothelial Dysfunction, Inflammation
Interventions
Ergocalciferol, Sugar pill
Drug · Other
Lead sponsor
Seth I. Sokol, M.D.
Other
Eligibility
18 Years and older
Enrollment
96 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2011
U.S. locations
2
States / cities
The Bronx, New York
Withdrawn Not applicable Interventional Accepts healthy volunteers

Evaluation of a Transdermal Vitamin D3 Delivery System, D3forME

NCT02174718
Conditions
Vitamin D Deficiency
Interventions
Transdermal D Patch, Oral vitamin D3, Placebo patch, Oral placebo
Dietary Supplement
Lead sponsor
University of Wisconsin, Madison
Other
Eligibility
18 Years to 85 Years
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2017
U.S. locations
1
States / cities
Madison, Wisconsin
Terminated Phase 4 Interventional Accepts healthy volunteers Results available

Metformin, Vitamin D, and Depression in Polycystic Ovary Syndrome (PCOS) Trial

NCT03380091
Conditions
PCOS, Depression, Vitamin D Deficiency, Insulin Resistance
Interventions
Metformin, Vitamin D
Drug
Lead sponsor
University of California, San Francisco
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
5 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2017 – 2019
U.S. locations
1
States / cities
San Francisco, California