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Showing 1–24 of 766 matching trials from the live ClinicalTrials.gov search.
Local D1 index available.
Completed Phase 2 Interventional Results available

Effects of Vitamin D in Parkinson's Disease (PD)

NCT01119131
Conditions
Parkinson Disease, Accidental Falls
Interventions
Vitamin D3, calcium, Placebo
Drug · Dietary Supplement · Other
Lead sponsor
VA Office of Research and Development
Federal
Eligibility
50 Years to 99 Years
Enrollment
101 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2015
U.S. locations
1
States / cities
Portland, Oregon
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
Conditions
Polycystic Ovary Syndrome
Interventions
Vitamin D, Placebo
Dietary Supplement · Drug
Lead sponsor
Milton S. Hershey Medical Center
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
36 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2014
U.S. locations
1
States / cities
Hershey, Pennsylvania
Conditions
Type 2 Diabetes, Nonalcoholic Fatty Liver Disease, Vitamin D Deficiency
Interventions
Ergocalciferol, placebo
Dietary Supplement
Lead sponsor
University of Massachusetts, Worcester
Other
Eligibility
10 Years to 50 Years
Enrollment
12 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2016
U.S. locations
1
States / cities
Worcester, Massachusetts
Completed Not applicable Interventional Accepts healthy volunteers

Bone Health in Pregnancy

NCT01145573
Conditions
Pregnancy
Interventions
Calcium or Placebo
Dietary Supplement
Lead sponsor
UCSF Benioff Children's Hospital Oakland
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
65 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2013
U.S. locations
1
States / cities
Oakland, California
Completed Phase 1 Interventional Accepts healthy volunteers Results available

Vitamin D as a Therapeutic Adjunct in the Stimulant Treatment of ADHD

NCT03103750
Conditions
ADHD
Interventions
Magnetic Resonance Imaging (MRI), PHNO, calcitriol, Placebo oral capsule, high-resolution research tomography, Dextro Amphetamine
Procedure · Drug · Dietary Supplement
Lead sponsor
Yale University
Other
Eligibility
18 Years to 50 Years
Enrollment
24 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2017 – 2023
U.S. locations
1
States / cities
New Haven, Connecticut
Conditions
Chronic Kidney Disease, Secondary Hyperparathyroidism, Chronic Renal Insufficiency, Chronic Renal Failure
Interventions
CTAP101 Capsules, CTAP101 Injection
Drug
Lead sponsor
OPKO IP Holdings II, Inc.
Industry
Eligibility
18 Years to 80 Years
Enrollment
28 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009
U.S. locations
12
States / cities
Peoria, Arizona • Evergreen Park, Illinois • Springfield, Massachusetts + 9 more
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 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
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 Not applicable Interventional Results available

Optimizing Vitamin D in the Elderly

NCT01554241
Conditions
Deficiency of Vitamin D3
Interventions
D3 2000 IU/day, D3 4000 IU/day, D3 50,000 IU weekly, vitamin D3 800 IU/day
Dietary Supplement
Lead sponsor
University of California, San Francisco
Other
Eligibility
65 Years and older
Enrollment
86 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2014
U.S. locations
1
States / cities
San Francisco, California
Conditions
Osteopenia, Renal Osteodystrophy
Interventions
pamidronate
Drug
Lead sponsor
US Department of Veterans Affairs
Federal
Eligibility
18 Years and older
Healthy volunteers
Healthy volunteers not accepted
Timeline
2002 – 2007
U.S. locations
1
States / cities
Seattle, Washington
Active, not recruiting Phase 3 Interventional Accepts healthy volunteers

VITAL Rhythm Study

NCT02178410
Conditions
Cardiovascular Disease
Interventions
Vitamin D3, Omega-3 fatty acids (fish oil), Fish oil placebo, Vitamin D3 placebo
Dietary Supplement · Drug
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
50 Years and older
Enrollment
25,119 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2026
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
X-linked Hypophosphatemia
Interventions
burosumab, Placebo
Biological · Other
Lead sponsor
Kyowa Kirin, Inc.
Industry
Eligibility
18 Years to 65 Years
Enrollment
134 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2018
U.S. locations
8
States / cities
Los Angeles, California • San Francisco, California • New Haven, Connecticut + 5 more
Active, not recruiting No phase listed Observational Accepts healthy volunteers

Early Check: Expanded Screening in Newborns

NCT03655223
Conditions
Spinal Muscular Atrophy, Fragile X Syndrome, Fragile X - Premutation, Duchenne Muscular Dystrophy, Hyperinsulinemic Hypoglycemia, Familial 1, Diabetes Mellitus, Adrenoleukodystrophy, Neonatal, Medium-chain Acyl-CoA Dehydrogenase Deficiency, Very Long Chain Acyl Coa Dehydrogenase Deficiency, Beta-ketothiolase Deficiency, Severe Combined Immunodeficiency Due to Adenosine Deaminase Deficiency, Primary Hyperoxaluria Type 1, Congenital Bile Acid Synthesis Defect Type 2, Pyridoxine-Dependent Epilepsy, Hereditary Fructose Intolerance, Hypophosphatasia, Hyperargininemia, Mucopolysaccharidosis Type 6, Argininosuccinic Aciduria, Citrullinemia, Type I, Wilson Disease, Maple Syrup Urine Disease, Type 1A, Maple Syrup Urine Disease, Type 1B, Biotinidase Deficiency, Neonatal Severe Primary Hyperparathyroidism, Intrinsic Factor Deficiency, Usher Syndrome Type 1D/F Digenic (Diagnosis), Cystic Fibrosis, Stickler Syndrome Type 2, Stickler Syndrome Type 1, Alport Syndrome, Autosomal Recessive, Alport Syndrome, X-Linked, Carbamoyl Phosphate Synthetase I Deficiency Disease, Carnitine Palmitoyl Transferase 1A Deficiency, Carnitine Palmitoyltransferase II Deficiency, Cystinosis, Chronic Granulomatous Disease, Cerebrotendinous Xanthomatoses, Maple Syrup Urine Disease, Type 2, Severe Combined Immunodeficiency Due to DCLRE1C Deficiency, Thyroid Dyshormonogenesis 6, Thyroid Dyshormonogenesis 5, Supravalvar Aortic Stenosis, Factor X Deficiency, Hemophilia A, Hemophilia B, Tyrosinemia, Type I, Fructose 1,6 Bisphosphatase Deficiency, Glycogen Storage Disease Type I, G6PD Deficiency, Glycogen Storage Disease II, Galactokinase Deficiency, Mucopolysaccharidosis Type IV A, Galactosemias, Guanidinoacetate Methyltransferase Deficiency, Agat Deficiency, Glutaryl-CoA Dehydrogenase Deficiency, Gtp Cyclohydrolase I Deficiency, Hyperinsulinism-Hyperammonemia Syndrome, Primary Hyperoxaluria Type 2, 3-Hydroxyacyl-CoA Dehydrogenase Deficiency, Long-chain 3-hydroxyacyl-CoA Dehydrogenase Deficiency, Mitochondrial Trifunctional Protein Deficiency, Sickle Cell Disease, Beta-Thalassemia, Holocarboxylase Synthetase Deficiency, 3-Hydroxy-3-Methylglutaric Aciduria, Primary Hyperoxaluria Type 3, Hermansky-Pudlak Syndrome 1, Hermansky-Pudlak Syndrome 4, Apparent Mineralocorticoid Excess, HSDB, CBAS1, Mucopolysaccharidosis Type 2, Mucopolysaccharidosis Type 1, Severe Combined Immunodeficiency, X Linked, Severe Combined Immunodeficiency Due to IL-7Ralpha Deficiency, Diabetes Mellitus, Permanent Neonatal, Isovaleric Acidemia, Severe Combined Immunodeficiency T-Cell Negative B-Cell Positive Due to Janus Kinase-3 Deficiency (Disorder), Jervell and Lange-Nielsen Syndrome 2, Hyperinsulinemic Hypoglycemia, Familial, 2, Diabetes Mellitus, Permanent Neonatal, With Neurologic Features, Jervell and Lange-Nielsen Syndrome 1, Lysosomal Acid Lipase Deficiency, CblF, 3-Methylcrotonyl CoA Carboxylase 1 Deficiency, 3-Methylcrotonyl CoA Carboxylase 2 Deficiency, Waardenburg Syndrome Type 2A, Methylmalonic Aciduria cblA Type, Methylmalonic Aciduria cblB Type, Methylmalonic Aciduria and Homocystinuria Type cblC, MAHCD, Methylmalonic Aciduria Due to Methylmalonyl-CoA Mutase Deficiency, Congenital Disorder of Glycosylation Type 1B, Mthfr Deficiency, Methylcobalamin Deficiency Type Cbl G (Disorder), Methylcobalamin Deficiency Type cblE, Usher Syndrome, Type 1B, N-acetylglutamate Synthase Deficiency, Ornithine Transcarbamylase Deficiency, Phenylketonurias, Waardenburg Syndrome Type 1, Congenital Hypothyroidism, Propionic Acidemia, Usher Syndrome, Type 1F, Pancreatic Agenesis 1, Hereditary Hypophosphatemic Rickets, Glycogen Storage Disease IXB, Glycogen Storage Disease IXC, MOWS, Epilepsy, Early-Onset, Vitamin B6-Dependent, Pyridoxal Phosphate-Responsive Seizures, Pituitary Hormone Deficiency, Combined, 1, Ptsd, Dihydropteridine Reductase Deficiency, Severe Combined Immunodeficiency Due to RAG1 Deficiency, Severe Combined Immunodeficiency Due to RAG2 Deficiency, Retinoblastoma, Multiple Endocrine Neoplasia Type 2B, Pseudohypoaldosteronism, Type I, Liddle Syndrome, Biotin-Responsive Basal Ganglia Disease, SCD, DIAR1, GSD1C, Acrodermatitis Enteropathica, Thyroid Dyshormonogenesis 1, Riboflavin Transporter Deficiency, Waardenburg Syndrome, Type 2E, SRD, Congenital Lipoid Adrenal Hyperplasia Due to STAR Deficiency, Barth Syndrome, Adrenocorticotropic Hormone Deficiency, Transcobalamin II Deficiency, Thyroid Dyshormonogenesis 3, Segawa Syndrome, Autosomal Recessive, Autosomal Recessive Nonsyndromic Hearing Loss, Thyroid Dyshormonogenesis 2A, Congenital Isolated Thyroid Stimulating Hormone Deficiency, Hypothyroidism Due to TSH Receptor Mutations, Usher Syndrome Type 1C, Usher Syndrome Type 1G (Diagnosis), Von Willebrand Disease, Type 3, Combined Immunodeficiency Due to ZAP70 Deficiency, Adenine Phosphoribosyltransferase Deficiency, Metachromatic Leukodystrophy, Canavan Disease, Menkes Disease, Carbonic Anhydrase VA Deficiency, Developmental and Epileptic Encephalopathy 2, 17 Alpha-Hydroxylase Deficiency, Smith-Lemli-Opitz Syndrome, Krabbe Disease, Glutathione Synthetase Deficiency, Mucopolysaccharidosis Type 7, Rett Syndrome, Molybdenum Cofactor Deficiency, Type A, Niemann-Pick Disease, Type C1, Niemann-Pick Disease Type C2, Ornithine Aminotransferase Deficiency, 3-Phosphoglycerate Dehydrogenase Deficiency, Leber Congenital Amaurosis 2, Dravet Syndrome, Mucopolysaccharidosis Type 3 A, Ornithine Translocase Deficiency, Carnitine-acylcarnitine Translocase Deficiency, Glucose Transporter Type 1 Deficiency Syndrome, Creatine Transporter Deficiency, Niemann-Pick Disease Type A, Pitt Hopkins Syndrome, Tuberous Sclerosis 1, Tuberous Sclerosis 2, Ataxia With Isolated Vitamin E Deficiency, Angelman Syndrome, Prader-Willi Syndrome, Homocystinuria, Permanent Neonatal Diabetes Mellitus, Transient Neonatal Diabetes Mellitus, Factor VII Deficiency, Glycogen Storage Disease Type IXA1, Glycogen Storage Disease, Type IXA2, Glycogen Storage Disease IC, Glycogen Storage Disease Type IB, Central Hypoventilation Syndrome With or Without Hirschsprung Disease
Interventions
Confirmatory Testing
Diagnostic Test
Lead sponsor
RTI International
Other
Eligibility
1 Day to 31 Days
Enrollment
30,000 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2018 – 2026
U.S. locations
1
States / cities
Research Triangle Park, North Carolina
Withdrawn Not applicable Interventional Accepts healthy volunteers

Calcimimetics in Hypophosphatemic Rickets

NCT00844740
Conditions
Familial Hypophosphatemic Rickets
Interventions
Cinacalcet
Drug
Lead sponsor
Children's Mercy Hospital Kansas City
Other
Eligibility
5 Years to 21 Years
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2012
U.S. locations
1
States / cities
Kansas City, Missouri
Completed Not applicable Interventional Results available

Vitamin D Oral Replacement in Asthma

NCT03686150
Conditions
Asthma, Vitamin D Deficiency, Pediatric Obesity
Interventions
Vitamin D3 oral regimen
Dietary Supplement
Lead sponsor
IDeA States Pediatric Clinical Trials Network
Network
Eligibility
6 Years to 17 Years
Enrollment
112 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2019 – 2021
U.S. locations
15
States / cities
Little Rock, Arkansas • Wilmington, Delaware • Honolulu, Hawaii + 12 more
Conditions
Cognitive Decline
Interventions
540,000 IU vitamin D3, Placebo
Drug
Lead sponsor
Vanderbilt University Medical Center
Other
Eligibility
18 Years and older
Enrollment
95 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2020
U.S. locations
7
States / cities
Aurora, Colorado • Boston, Massachusetts • New York, New York + 3 more
Conditions
Hypertension, Left Ventricular Hypertrophy
Interventions
cholecalciferol (Vitamin D), Placebo
Dietary Supplement
Lead sponsor
Wayne State University
Other
Eligibility
30 Years to 74 Years
Enrollment
354 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2015
U.S. locations
1
States / cities
Detroit, Michigan
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
Completed Not applicable Interventional Accepts healthy volunteers

Understanding Effects of Calcium on the Gut-Bone Axis

NCT06383117
Conditions
Healthy, Adult, Calcium, Bone Resorption, Endocrine; Obesity
Interventions
Calcium carbonate, Placebo Control
Dietary Supplement
Lead sponsor
University of Georgia
Other
Eligibility
18 Years to 45 Years
Enrollment
14 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2023 – 2024
U.S. locations
1
States / cities
Athens, Georgia
Conditions
Thyroid, PD-1, Cancer
Interventions
blood draw and questionnaire completion, questionnaire completion, blood collection
Other
Lead sponsor
Icahn School of Medicine at Mount Sinai
Other
Eligibility
18 Years and older
Enrollment
17 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2021 – 2028
U.S. locations
1
States / cities
New York, New York
Conditions
Bone Density, Bone Health, Fractures
Interventions
Vitamin D3 placebo, Fish oil placebo, Omega-3 fatty acids (fish oil), Vitamin D3
Dietary Supplement · Drug
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
50 Years and older
Enrollment
25,871 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2019 – 2026
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Stress Fracture
Interventions
Calcium & Vitamin D
Dietary Supplement
Lead sponsor
Creighton University
Other
Eligibility
Female only
Enrollment
5,201 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2002 – 2006
U.S. locations
1
States / cities
Omaha, Nebraska