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Showing 1–24 of 767 matching trials from the live ClinicalTrials.gov search.
Local D1 index available.
Completed Phase 4 Interventional Accepts healthy volunteers

How Does Magnesium Status Influence Calcium Homeostasis?

NCT01593501
Conditions
Magnesium Deficiency, Calcium Metabolism Disorders
Interventions
vitamin D3
Dietary Supplement
Lead sponsor
University of Wisconsin, Madison
Other
Eligibility
30 Years to 75 Years · Female only
Enrollment
39 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2014
U.S. locations
1
States / cities
Madison, Wisconsin
Completed Phase 2 Interventional Accepts healthy volunteers

Vitamin D and Arterial Stiffness in Elderly

NCT03649802
Conditions
Vitamin D Deficiency, Arterial Stiffness
Interventions
Low dose vitamin D3, High dose vitamin D3
Dietary Supplement
Lead sponsor
Texas Tech University Health Sciences Center
Other
Eligibility
65 Years to 89 Years
Enrollment
52 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2018 – 2021
U.S. locations
1
States / cities
Lubbock, Texas
Completed Not applicable Interventional Accepts healthy volunteers Results available

Vitamin D and Fish Oil for Autoimmune Disease, Inflammation and Knee Pain

NCT01351805
Conditions
Autoimmune Diseases, Systemic Inflammatory Process, Knee Pain Chronic, Osteoarthritis, Rheumatoid Arthritis
Interventions
Fish Oil, Vitamin D, placebo pill
Drug · Dietary Supplement · Other
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
50 Years and older
Enrollment
25,871 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2025
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Vitamin D Deficiency, Stem Cell Transplant Complications, Pediatric Cancer, Blood Disorder, Pediatric Acute Myeloid Leukemia, Pediatric Acute Lymphoid Leukemia, Myelodysplastic Syndromes, Sickle Cell Anemia in Children, Aplastic Anemia, Thalassemia in Children
Interventions
Vitamin D3, Standard Vitamin D3 Supplementation
Dietary Supplement
Lead sponsor
Phoenix Children's Hospital
Other
Eligibility
1 Year to 25 Years
Enrollment
49 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017 – 2019
U.S. locations
1
States / cities
Phoenix, Arizona
Conditions
Melanoma
Interventions
Not listed
Lead sponsor
New Mexico Cancer Research Alliance
Other
Eligibility
18 Years and older
Enrollment
9 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2010
U.S. locations
1
States / cities
Albuquerque, New Mexico
Conditions
X-Linked Hypophosphatemia
Interventions
KRN23
Biological
Lead sponsor
Kyowa Kirin, Inc.
Industry
Eligibility
Not listed
Enrollment
20 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2018
U.S. locations
5
States / cities
San Francisco, California • New Haven, Connecticut • Indianapolis, Indiana + 2 more
Conditions
Sarcopenia
Interventions
Placebo, HMB plus Vitamin D, Non-Exercise, Exercise
Dietary Supplement · Drug · Behavioral
Lead sponsor
Metabolic Technologies Inc.
Industry
Eligibility
60 Years and older
Enrollment
238 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2014 – 2019
U.S. locations
1
States / cities
Ames, Iowa
Completed Not applicable Interventional Accepts healthy volunteers

Drug Metabolizing Enzyme and Transporter Function in Chronic Kidney Disease

NCT02360644
Conditions
Chronic Kidney Diseases, Deficiency, Vitamin D
Interventions
Cholecalciferol
Dietary Supplement
Lead sponsor
University of Colorado, Denver
Other
Eligibility
18 Years to 70 Years
Enrollment
23 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2014 – 2019
U.S. locations
2
States / cities
Aurora, Colorado • Pittsburgh, Pennsylvania
Conditions
Vitamin D Deficiency
Interventions
1,000 IU vitamin D2, placebo capsule, mushrooms, UVB-treated mushrooms, 400 IU vitamin D2, UVB-treated mushrooms, 1,000 IU vitamin D2
Dietary Supplement · Other
Lead sponsor
USDA, Western Human Nutrition Research Center
Federal
Eligibility
20 Years to 59 Years
Enrollment
48 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2011
U.S. locations
1
States / cities
Davis, California
Active, not recruiting Phase 3 Interventional Accepts healthy volunteers Results available

Vitamin D and Omega-3 Trial (VITAL)

NCT01169259
Conditions
Cancer, Cardiovascular Disease
Interventions
vitamin D3, omega-3 fatty acids (fish oil), Vitamin D3 placebo, Fish oil placebo
Dietary Supplement · Drug
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
50 Years and older
Enrollment
25,871 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2026
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Muscle Power
Interventions
Vitamin D, Placebo
Dietary Supplement
Lead sponsor
Oklahoma State University
Other
Eligibility
18 Years to 35 Years
Enrollment
103 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2013
U.S. locations
1
States / cities
Stillwater, Oklahoma
Conditions
Solid Tumors
Interventions
Doxercalciferol
Drug
Lead sponsor
M.D. Anderson Cancer Center
Other
Eligibility
2 Years to 26 Years
Enrollment
1 participant
Healthy volunteers
Healthy volunteers not accepted
Timeline
2007 – 2010
U.S. locations
1
States / cities
Houston, Texas
Completed Phase 1Phase 2 Interventional Accepts healthy volunteers

Changes in Breast Cancer Biomarkers Using Synergistic Prostaglandin Inhibitors

NCT01425476
Conditions
Breast Cancer
Interventions
Celecoxib, Placebo, Cholecalciferol
Drug
Lead sponsor
Hartford Hospital
Other
Eligibility
18 Years and older · Female only
Enrollment
45 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2016
U.S. locations
1
States / cities
Grand Forks, North Dakota
Terminated Not applicable Interventional Accepts healthy volunteers Results available

Cholecalciferol and Flu Vaccine in Treating Healthy Participants

NCT01561989
Conditions
Healthy, no Evidence of Disease
Interventions
cholecalciferol, questionnaire administration, trivalent influenza vaccine
Dietary Supplement · Other · Biological
Lead sponsor
Roswell Park Cancer Institute
Other
Eligibility
18 Years to 64 Years
Enrollment
11 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2015
U.S. locations
1
States / cities
Buffalo, New York
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 Results available

Vitamin D in HIV-Infected Patients on HAART

NCT01250899
Conditions
Vitamin D Deficiency, HIV
Interventions
Vitamin D
Dietary Supplement
Lead sponsor
University of California, Los Angeles
Other
Eligibility
18 Years to 90 Years
Enrollment
122 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2012
U.S. locations
1
States / cities
Los Angeles, California
Conditions
Heart Failure
Interventions
Paricalcitol
Drug
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years and older
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Hypovitaminosis D
Interventions
vitamin D supplementation
Dietary Supplement
Lead sponsor
University of Wisconsin, Madison
Other
Eligibility
18 Years and older
Healthy volunteers
Healthy volunteers not accepted
Timeline
Started 2005
U.S. locations
1
States / cities
Madison, Wisconsin
Completed Not applicable Interventional Accepts healthy volunteers

Vitamin D3 Supplementation Pilot Study

NCT01546103
Conditions
Vitamin D Deficiency
Interventions
Cholecalciferol
Dietary Supplement
Lead sponsor
Children's Hospital of Philadelphia
Other
Eligibility
12 Years to 17 Years
Enrollment
39 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2012
U.S. locations
1
States / cities
Philadelphia, Pennsylvania
Terminated Phase 4 Interventional Results available

Effect of Vitamin D Supplementation on Balance in CKD

NCT03710161
Conditions
Renal Insufficiency, Chronic, Kidney Failure, Chronic
Interventions
Vitamin D
Drug
Lead sponsor
University of Nebraska
Other
Eligibility
21 Years to 70 Years
Enrollment
5 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2019 – 2020
U.S. locations
1
States / cities
Omaha, Nebraska
Conditions
Low 25-hydroxyvitamin D Concentrations
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Wake Forest University Health Sciences
Other
Eligibility
65 Years to 89 Years
Enrollment
15 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2017
U.S. locations
1
States / cities
Winston-Salem, North Carolina
Conditions
Stage, Colon Cancer, Stage I-III Colon Cancer, Stage IV Colon Cancer With Resectable Liver Metastases
Interventions
Vitamin D3, Placebo
Drug
Lead sponsor
Dana-Farber Cancer Institute
Other
Eligibility
18 Years and older
Enrollment
80 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2027
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Hypophosphatasia (HPP)
Interventions
asfotase alfa
Biological
Lead sponsor
Alexion Pharmaceuticals, Inc.
Industry
Eligibility
Up to 36 Months
Enrollment
11 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2010
U.S. locations
6
States / cities
Little Rock, Arkansas • Wilmington, Delaware • Springfield, Missouri + 3 more
Completed Phase 2 Interventional Accepts healthy volunteers

Efficacy of Vitamin D in Colorectal Cancer Chemoprevention

NCT01574027
Conditions
Colorectal Cancer
Interventions
Vitamin D3 (cholecalciferol), Placebo
Drug
Lead sponsor
University of Illinois at Chicago
Other
Eligibility
50 Years and older
Enrollment
55 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2011
U.S. locations
1
States / cities
Chicago, Illinois