Independent directory Public ClinicalTrials.gov records United States
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Showing 25–48 of 121 matching trials from the live ClinicalTrials.gov search.
Conditions
Post-Acute COVID-19 Syndrome, Fatigue
Interventions
Dietary intervention to mitigate Post-Acute COVID-19 Syndrome, Attention Control
Other
Lead sponsor
University of Maryland, Baltimore
Other
Eligibility
50 Years to 94 Years
Enrollment
56 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2025 – 2028
U.S. locations
1
States / cities
Baltimore, Maryland
Conditions
brca1 Mutation Carrier, brca2 Mutation Carrier, Breast Cancer
Interventions
cholecalciferol, placebo
Dietary Supplement · Other
Lead sponsor
SWOG Cancer Research Network
Network
Eligibility
18 Years to 50 Years · Female only
Enrollment
208 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2017
U.S. locations
360
States / cities
Anniston, Alabama • Mobile, Alabama • Anchorage, Alaska + 230 more
Conditions
Prostate Adenocarcinoma, Stage I Prostate Cancer, Stage IIA Prostate Cancer, Stage IIB Prostate Cancer
Interventions
Cholecalciferol, Genistein, Laboratory Biomarker Analysis, Pharmacological Study, Placebo
Drug · Other
Lead sponsor
National Cancer Institute (NCI)
NIH
Eligibility
18 Years and older · Male only
Enrollment
15 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2014
U.S. locations
11
States / cities
Birmingham, Alabama • Baltimore, Maryland • Burlington, Massachusetts + 6 more
Conditions
HIV-1 Infection
Interventions
EFV/FTC/TDF, Calcium Carbonate, Vitamin D3, Placebo for calcium carbonate, Placebo for vitamin D3
Drug
Lead sponsor
Advancing Clinical Therapeutics Globally for HIV/AIDS and Other Infections
Network
Eligibility
18 Years and older
Enrollment
167 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2013
U.S. locations
38
States / cities
Birmingham, Alabama • Los Angeles, California • Palo Alto, California + 27 more
Completed Not applicable Interventional Accepts healthy volunteers Results available

Low vs. Moderate to High Dose Vitamin D for Prevention of COVID-19

NCT04868903
Conditions
SARS-CoV-2 Infection
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
University of Chicago
Other
Eligibility
18 Years and older
Enrollment
1,475 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2024
U.S. locations
2
States / cities
Chicago, Illinois
Completed Phase 2 Interventional Results available

High Dose Vitamin D for Sickle Cell Disease

NCT01331148
Conditions
Sickle Cell Disease
Interventions
Vitamin D, Placebo
Drug · Other
Lead sponsor
Wake Forest University Health Sciences
Other
Eligibility
7 Years to 21 Years
Enrollment
46 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2013
U.S. locations
1
States / cities
Atlanta, Georgia
Conditions
Anemia of Chronic Kidney Disease
Interventions
Cholecalciferol
Drug
Lead sponsor
Johns Hopkins University
Other
Eligibility
1 Year to 21 Years
Enrollment
34 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2015
U.S. locations
1
States / cities
Baltimore, Maryland
Conditions
Obesity, Pediatric, Obesity, Childhood, Obesity, Morbid, Vitamin D Deficiency
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Columbia University
Other
Eligibility
5 Years to 11 Years
Enrollment
6 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2019
U.S. locations
1
States / cities
New York, New York
Conditions
Graves Disease, Graves' Disease, Hyperthyroidism
Interventions
Ergocalciferol 50,000 IU, Methimazole
Drug
Lead sponsor
Northwell Health
Other
Eligibility
9 Years to 17 Years
Enrollment
30 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2025 – 2027
U.S. locations
1
States / cities
New Hyde Park, New York
Conditions
Obesity
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Mayo Clinic
Other
Eligibility
12 Years to 18 Years
Enrollment
51 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2012
U.S. locations
1
States / cities
Rochester, Minnesota
Terminated Phase 2 Interventional Results available

High Dose Vitamin D vs Standard Dose Vitamin D Study

NCT01988090
Conditions
Breast Cancer
Interventions
800 IU Vitamin D Supplement, 50,000 IU Vitamin D supplement
Drug
Lead sponsor
Mothaffar Rimawi
Other
Eligibility
18 Years and older · Female only
Enrollment
93 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2013 – 2018
U.S. locations
2
States / cities
St Louis, Missouri • Houston, Texas
Conditions
Vitamin D Deficiency
Interventions
Treatment
Drug
Lead sponsor
Johns Hopkins All Children's Hospital
Other
Eligibility
36 Months to 18 Years
Enrollment
26 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2019
U.S. locations
1
States / cities
St. Petersburg, Florida
Conditions
Stage IV Colon Cancer, Stage IV Rectal Cancer
Interventions
leucovorin calcium, bevacizumab, cholecalciferol, fluorouracil, oxaliplatin, pharmacological study
Drug · Biological · Dietary Supplement + 1 more
Lead sponsor
Roswell Park Cancer Institute
Other
Eligibility
18 Years to 79 Years
Enrollment
10 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2012
U.S. locations
1
States / cities
Buffalo, New York
Conditions
Fracture
Interventions
Vitamin D3, Placebo
Drug · Other
Lead sponsor
University of Maryland, Baltimore
Other
Eligibility
18 Years to 50 Years
Enrollment
102 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2021
U.S. locations
1
States / cities
Baltimore, Maryland
Completed Phase 2 Interventional Accepts healthy volunteers

Metabolic Syndrome and Insulin Resistance at Allina

NCT01545830
Conditions
Metabolic Syndrome
Interventions
vitamin D3 (cholecalciferol)
Dietary Supplement
Lead sponsor
Allina Health System
Other
Eligibility
18 Years and older
Enrollment
84 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2014
U.S. locations
1
States / cities
Minneapolis, Minnesota
Completed Phase 1Phase 2 Interventional Accepts healthy volunteers

Changes in Biomarkers Using Prostaglandin Inhibitors

NCT01769625
Conditions
Biomarker Change Linked to Breast Cancer
Interventions
placebo/celecoxib 400 mg and cholecalciferol 400 IU/cholecalciferol 2,000 IU
Drug
Lead sponsor
Hartford Hospital
Other
Eligibility
18 Years and older · Female only
Enrollment
31 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2016
U.S. locations
1
States / cities
Grand Forks, North Dakota
Conditions
Breast, Breast Cancer, Osteoporosis
Interventions
High Dose Vitamin D, Standard of Care Vitamin D
Dietary Supplement
Lead sponsor
Wake Forest University Health Sciences
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
7 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2021 – 2024
U.S. locations
1
States / cities
Charlotte, North Carolina
Conditions
Chronic Kidney Disease, Secondary Hyperparathyroidism, Chronic Renal Insufficiency, Chronic Renal Failure
Interventions
CTA018 Injection
Drug
Lead sponsor
OPKO IP Holdings II, Inc.
Industry
Eligibility
18 Years to 80 Years
Enrollment
41 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2010
U.S. locations
5
States / cities
Pembroke Pines, Florida • Meridian, Idaho • Springfield, Massachusetts + 2 more
Conditions
Bariatric Surgery
Interventions
Not listed
Lead sponsor
Texas Tech University
Other
Eligibility
18 Years to 60 Years
Enrollment
31 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2013
U.S. locations
1
States / cities
Lubbock, Texas
Conditions
Diabetes Mellitus, Type 1, Hypoglycemia, Diabetes Mellitus, Diabetes, Autoimmune
Interventions
Cholecalciferol, Omega 3 fatty acid
Drug
Lead sponsor
Rodolfo Alejandro
Other
Eligibility
6 Years to 65 Years
Enrollment
27 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2024
U.S. locations
1
States / cities
Miami, Florida
Conditions
Crohn's Disease, Vitamin D Deficiency
Interventions
Cholecalciferol 10,000 IU, Cholecalciferol 400 IU
Drug
Lead sponsor
University of Michigan
Other
Eligibility
18 Years to 75 Years
Enrollment
11 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2016
U.S. locations
4
States / cities
Indianapolis, Indiana • Iowa City, Iowa • Ann Arbor, Michigan + 1 more
Conditions
Opioid Use Disorder
Interventions
[11C]-PHNO, Calcitriol, Placebo Control, PET Scan
Drug · Dietary Supplement · Other + 1 more
Lead sponsor
Yale University
Other
Eligibility
18 Years to 50 Years
Enrollment
5 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2024 – 2025
U.S. locations
1
States / cities
New Haven, Connecticut
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
Conditions
Vitamin D Deficiency, Nephrolithiasis
Interventions
vitamin D (ergocalciferol)
Drug
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
18 Years and older
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2010
U.S. locations
1
States / cities
Boston, Massachusetts