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ClinicalTrials.gov public records Last synced Nov 14, 2026, 8:35 AM EST

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Showing 1–24 of 438 matching trials from the live ClinicalTrials.gov search.

Filters: Intervention: Vitamin D placebo Clear all

Conditions: COVID-19
Interventions: vitamin D, Placebo; Dietary Supplement
Lead sponsor: Brigham and Women's Hospital; Other
Eligibility: 18 Years and older
Enrollment: 2,024 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2020 – 2024
U.S. locations: 1
States / cities: Boston, Massachusetts

Conditions: Arthritis, Rheumatoid, Vitamin D Deficiency
Interventions: Placebo in arm A and Vitamin D in arm B, vitamin D 3 for arm A ,and matching placebo for arm B; Drug
Lead sponsor: Indiana University; Other
Eligibility: 18 Years and older
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2009 – 2011
U.S. locations: 1
States / cities: Indianapolis, Indiana

Conditions: Female Hormone Profile
Interventions: Vitamin D (Cholecalciferol ), Placebo Group; Dietary Supplement
Lead sponsor: University of Southern California; Other
Eligibility: 18 Years to 35 Years · Female only
Enrollment: 20 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2025 – 2026
U.S. locations: 1
States / cities: Los Angeles, California

Conditions: Vitamin D Deficiency
Interventions: 400 IU Vitamin D3 (cholecalciferol), 2400 IU Vitamin D3 (cholecalciferol), 6400 IU Vitamin D3 (cholecalciferol); Drug
Lead sponsor: Medical University of South Carolina; Other
Eligibility: 18 Years to 45 Years · Female only
Enrollment: 460 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2006 – 2012
U.S. locations: 2
States / cities: Rochester, New York • Charleston, South Carolina

Conditions: Basal Cell Carcinoma, Basal Cell Nevus Syndrome
Interventions: Dietary Vitamin D3 pre-treatment, Photodynamic therapy, Serum Maintenance Vitamin D3; Drug · Radiation
Lead sponsor: Case Comprehensive Cancer Center; Other
Eligibility: Not listed
Enrollment: 37 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2018 – 2023
U.S. locations: 2
States / cities: Phoenix, Arizona • Cleveland, Ohio

Conditions: Healthy, Vitamin D Deficiency
Interventions: ergocalciferol, placebo pill; Dietary Supplement · Other
Lead sponsor: Massachusetts General Hospital; Other
Eligibility: 9 Years to 18 Years · Female only
Enrollment: 90 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2010 – 2013
U.S. locations: 1
States / cities: Boston, Massachusetts

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 – 2031
U.S. locations: 1
States / cities: Boston, Massachusetts

Conditions: Diabetes Mellitus, Chronic Kidney Disease, Diabetic Kidney Disease
Interventions: Cholecalciferol, Placebo; Dietary Supplement
Lead sponsor: University of Washington; Other
Eligibility: 18 Years and older
Enrollment: 22 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2007 – 2010
U.S. locations: 1
States / cities: Seattle, Washington

Conditions: COVID-19, Coronavirus Infection, Sars-CoV2, Corona Virus Infection, COVID, Coronavirus, Coronavirus-19, Coronavirus 19
Interventions: Hydroxychloroquine, Vitamin C, Vitamin D, Zinc; Drug · Dietary Supplement
Lead sponsor: ProgenaBiome; Other
Eligibility: 18 Years and older
Enrollment: 254 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2020 – 2024
U.S. locations: 1
States / cities: Ventura, California

Conditions: End Stage Renal Disease
Interventions: ergocalciferol supplementation, placebo; Dietary Supplement · Other
Lead sponsor: Dialysis Clinic, Inc.; Industry
Eligibility: 18 Years and older
Enrollment: 470 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2011 – 2015
U.S. locations: 12
States / cities: Redding, California • Albany, Georgia • Shreveport, Louisiana + 9 more

Conditions: Nonalcoholic Fatty Liver Disease, Nonalcoholic Steatohepatitis
Interventions: Vitamin E, Placebo; Drug
Lead sponsor: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); NIH
Eligibility: 18 Years and older
Enrollment: 200 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2022 – 2025
U.S. locations: 9
States / cities: La Jolla, California • Los Angeles, California • San Francisco, California + 6 more

Conditions: Systemic Lupus Erythematosus, SLE, Lupus
Interventions: Vitamin D3, Vitamin D3 placebo; Drug
Lead sponsor: National Institute of Allergy and Infectious Diseases (NIAID); NIH
Eligibility: 18 Years and older
Enrollment: 57 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2008 – 2011
U.S. locations: 8
States / cities: Birmingham, Alabama • San Francisco, California • Boston, Massachusetts + 5 more

Conditions: Hypovitaminosis D
Interventions: Vitamin D3, Calcium, and Vitamin C; Dietary Supplement
Lead sponsor: Atlantic Health System; Other
Eligibility: 6 Years to 21 Years
Enrollment: 200 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2027 – 2032
U.S. locations: 1
States / cities: Morristown, New Jersey

Conditions: Osteoporosis, Aging
Interventions: Vitamin D3, Calcium Citrate (Citracal); Dietary Supplement
Lead sponsor: Creighton University; Other
Eligibility: 57 Years and older · Female only
Enrollment: 273 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2007 – 2011
U.S. locations: 1
States / cities: Omaha, Nebraska

Conditions: Male Infertility
Interventions: Antioxidant Supplement, Placebo; Drug · Other
Lead sponsor: Yale University; Other
Eligibility: 18 Years and older · Male only
Enrollment: 171 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2015 – 2018
U.S. locations: 10
States / cities: Los Angeles, California • San Francisco, California • Sunnyvale, California + 7 more

Conditions: Clonal Cytopenia of Undetermined Significance, High Grade B-Cell Lymphoma With MYC and BCL2 or BCL6 Rearrangements, Recurrent Diffuse Large B-Cell Lymphoma, Recurrent Hodgkin Lymphoma, Recurrent Lymphoma, Refractory Diffuse Large B-Cell Lymphoma, Refractory Lymphoma, Chronic Myelomonocytic Leukemia
Interventions: Ascorbic Acid, Carboplatin, Cisplatin, Cytarabine, Dexamethasone, Etoposide, Gemcitabine Hydrochloride, Ifosfamide, Laboratory Biomarker Analysis, Oxaliplatin, Placebo Administration, Questionnaire Administration, Rituximab, Decitabine, Biospecimen Collection, Core Biopsy, Bone Marrow Aspiration, Bone Marrow Biopsy, Echocardiography, Positron Emission Tomography, Magnetic Resonance Imaging, Central Venous Cannula Insertion, Portacath Placement, Computed Tomography, Decitabine and Cedazuridine; Dietary Supplement · Drug · Other + 2 more
Lead sponsor: Mayo Clinic; Other
Eligibility: 18 Years and older
Enrollment: 80 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2018 – 2033
U.S. locations: 4
States / cities: Mankato, Minnesota • Rochester, Minnesota • Eau Claire, Wisconsin + 1 more

Conditions: Bone Alteration, Dietary Modification
Interventions: Calcium/Vitamin D, Placebo; Dietary Supplement
Lead sponsor: United States Army Research Institute of Environmental Medicine; Federal
Eligibility: 17 Years to 42 Years
Enrollment: 175 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2015
U.S. locations: 1
States / cities: Columbia, South Carolina

Conditions: Pre-Diabetic
Interventions: Calcitriol capsules, Oral Placebo; Drug
Lead sponsor: Mayo Clinic; Other
Eligibility: 20 Years to 45 Years
Enrollment: 17 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2020 – 2021
U.S. locations: 1
States / cities: Rochester, Minnesota

Conditions: Vitamin D Deficiency
Interventions: Placebo, 800 IU/day vitamin D supplementation with feedings in the first 28 days after birth, Usual Care; Dietary Supplement · Other
Lead sponsor: The University of Texas Health Science Center, Houston; Other
Eligibility: 24 Hours to 96 Hours
Enrollment: 180 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2022 – 2027
U.S. locations: 1
States / cities: Houston, Texas

Conditions: Health, Subjective
Interventions: Experimental supplement, Placebo; Dietary Supplement
Lead sponsor: Auburn University; Other
Eligibility: 21 Years to 40 Years · Female only
Enrollment: 94 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2018 – 2019
U.S. locations: 1
States / cities: Auburn, Alabama

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: Determine Effect of Vitamin D on Bone Health in Elderly African American Women
Interventions: Vitamin D 3, placebo; Dietary Supplement · Other
Lead sponsor: Winthrop University Hospital; Other
Eligibility: 60 Years and older · Female only
Enrollment: 260 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2010 – 2016
U.S. locations: 1
States / cities: Mineola, New York

Conditions: Healthy
Interventions: Vitamin D, Placebo; Dietary Supplement
Lead sponsor: University of Kentucky; Other
Eligibility: 18 Years and older
Enrollment: 45 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2011 – 2012
U.S. locations: 1
States / cities: Lexington, Kentucky

Conditions: Musculoskeletal Pain
Interventions: Vitamin D 2, Vitamin D2 Placebo; Drug
Lead sponsor: University of North Carolina, Chapel Hill; Other
Eligibility: 18 Years to 65 Years
Enrollment: 71 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2023 – 2024
U.S. locations: 4
States / cities: Worcester, Massachusetts • St Louis, Missouri • Camden, New Jersey + 1 more

Search by objective public record fields.

Vitamin D for COVID-19 Trial

Vitamin D Deficiency Causes Immune Dysfunction and Enables or Perpetuates the Development of Rheumatoid Arthritis

Acute Vitamin D Supplementation on Testosterone in Females

Establishing the Vitamin D Requirements During Lactation

Vitamin D as a Nutritional Neoadjuvant During Photodynamic Therapy of Basal Cell Carcinoma

Vitamin D Deficiency in Adolescent Girls

Vitamin D and Omega-3 Trial (VITAL)

Randomized Controlled Trial of Vitamin D3 in Diabetic Kidney Disease

A Study of Hydroxychloroquine, Vitamin C, Vitamin D, and Zinc for the Prevention of COVID-19 Infection

Safety and Effects of Supplementation With Ergocalciferol on Erythropoietin Dosing in Hemodialysis Patients

Vitamin E Dosing Study

Vitamin D3 in Systemic Lupus Erythematosus

The Effectiveness of a Weight-dependent Algorithm for Dosing Vitamin D.

Vitamin D Supplementation in Older Women

Males, Antioxidants, and Infertility Trial

Ascorbic Acid and Chemotherapy for the Treatment of Relapsed or Refractory Lymphoma, CCUS, and Chronic Myelomonocytic Leukemia

Efficacy of a Once Daily Calcium and Vitamin D Fortified Food Product to Improve Bone Microarchitecture

Effect of 1,25-dihydroxyvitamin D3, Treatment on Insulin Secretion and Muscle Strength in Pre-diabetic Persons

ViDES Trial (Vitamin D Extra Supplementation)

The Effects of a Multi-vitamin Supplement in Adult Females

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

Vitamin D and Osteoporosis Prevention in Elderly African American Women

A Prospective Trial on the Effects of Vitamin D Supplementation in Collegiate Swimmers and Divers

Vitamin D to ENhance TraUma REcovery