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ClinicalTrials.gov public records Last synced Nov 15, 2026, 2:51 AM EST

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Showing 73–96 of 121 matching trials from the live ClinicalTrials.gov search.

Filters: Intervention: Vitamin D3 - high dose Clear all

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: Reproductive Issues
Interventions: Vitamin D, Placebo; Dietary Supplement · Other
Lead sponsor: National Institute of Environmental Health Sciences (NIEHS); NIH
Eligibility: 19 Years to 40 Years · Female only
Enrollment: 998 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2023 – 2024
U.S. locations: 2
States / cities: Detroit, Michigan • Research Triangle Park, North Carolina

Conditions: Hip Arthropathy, Knee Arthropathy, Vitamin D Deficiency
Interventions: Vitamin D3; Dietary Supplement
Lead sponsor: Brigham and Women's Hospital; Other
Eligibility: 18 Years and older
Enrollment: 900 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2019 – 2024
U.S. locations: 1
States / cities: Boston, Massachusetts

Conditions: Short Segment Barrett's Esophagus, Long Segment Barrett's Esophagus
Interventions: Omeprazole, Vitamin D3, upper endoscopy, Metformin; Drug · Procedure
Lead sponsor: Case Comprehensive Cancer Center; Other
Eligibility: 18 Years and older
Enrollment: 26 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2010 – 2016
U.S. locations: 3
States / cities: Beachwood, Ohio • Cleveland, Ohio

Conditions: Male Osteoporosis
Interventions: Teriparatide or human parathyroid hormone (PTH) 1-34, Cinacalcet, placebo tablet, Calcium citrate tablet, Vitamin D3; Drug · Dietary Supplement
Lead sponsor: VA Office of Research and Development; Federal
Eligibility: 60 Years to 85 Years · Male only
Enrollment: 40 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2019 – 2025
U.S. locations: 1
States / cities: San Francisco, California

Conditions: Breast Cancer
Interventions: vitamin D3; Drug
Lead sponsor: Carol Fabian, MD; Other
Eligibility: Up to 55 Years · Female only
Enrollment: 30 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2009 – 2011
U.S. locations: 1
States / cities: Kansas City, Kansas

Conditions: Cystic Fibrosis
Interventions: Not listed
Lead sponsor: Emory University; Other
Eligibility: 18 Years to 50 Years
Enrollment: 50 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2014 – 2018
U.S. locations: 1
States / cities: Atlanta, Georgia

Conditions: Vitamin D Deficiency
Interventions: High dose Vitamin D3, Low dose Vitamin D3; Dietary Supplement
Lead sponsor: Texas Tech University Health Sciences Center; Other
Eligibility: 65 Years to 89 Years
Enrollment: 14 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2018 – 2019
U.S. locations: 1
States / cities: Lubbock, Texas

Conditions: Acute Respiratory Distress Syndrome, Vitamin D Deficiency, Critical Illness
Interventions: Vitamin D3, Placebo; Drug
Lead sponsor: Massachusetts General Hospital; Other
Eligibility: 18 Years and older
Enrollment: 1,358 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2017 – 2018
U.S. locations: 47
States / cities: Fresno, California • Los Angeles, California • Sacramento, California + 34 more

Conditions: Multiple Sclerosis, Vitamin D Deficiency
Interventions: Cholecalciferol; Drug
Lead sponsor: Johns Hopkins University; Other
Eligibility: 18 Years to 55 Years
Enrollment: 40 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2010 – 2013
U.S. locations: 1
States / cities: Baltimore, Maryland

Conditions: Colorectal Cancer
Interventions: calcium carbonate, cholecalciferol, immunohistochemistry staining method, laboratory biomarker analysis, pharmacological study, biopsy; Dietary Supplement · Other · Procedure
Lead sponsor: Roswell Park Cancer Institute; Other
Eligibility: 18 Years to 120 Years
Enrollment: 8 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2006 – 2009
U.S. locations: 1
States / cities: Buffalo, New York

Conditions: Hematopoietic Stem Cell Transplant
Interventions: Cholecalciferol; Drug
Lead sponsor: Children's Hospital Los Angeles; Other
Eligibility: 0 Years to 25 Years
Enrollment: 33 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2018 – 2020
U.S. locations: 1
States / cities: Los Angeles, California

Conditions: Cystic Fibrosis, Dysbiosis
Interventions: Vitamin D3, Placebo vitamin D3, Inulin, Placebo Inulin; Drug
Lead sponsor: Emory University; Other
Eligibility: 18 Years and older
Enrollment: 40 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2020 – 2022
U.S. locations: 1
States / cities: Atlanta, Georgia

Conditions: Metastatic Colorectal Cancer
Interventions: FOLFOX + bevacizumab, Vitamin D; Drug · Dietary Supplement
Lead sponsor: Dana-Farber Cancer Institute; Other
Eligibility: 18 Years and older
Enrollment: 139 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2012 – 2019
U.S. locations: 18
States / cities: Boise, Idaho • Fruitland, Idaho • Meridian, Idaho + 13 more

Conditions: Vitamin D Deficiency
Interventions: cholecalciferol; Dietary Supplement
Lead sponsor: Tufts University; Other
Eligibility: 50 Years to 69 Years
Enrollment: 62 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2010 – 2012
U.S. locations: 1
States / cities: Boston, Massachusetts

Conditions: Vitamin D Deficiency, Cystic Fibrosis
Interventions: Vitamin D3; Dietary Supplement
Lead sponsor: University of Southern California; Other
Eligibility: 18 Years and older
Enrollment: 6 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2019 – 2022
U.S. locations: 1
States / cities: Los Angeles, California

Conditions: Vitamin D Deficiency
Interventions: cholecalciferol (vitamin D); Dietary Supplement
Lead sponsor: University of Miami; Other
Eligibility: 65 Years to 95 Years
Enrollment: 105 participants
Healthy volunteers: Accepts healthy volunteers
Timeline: 2008 – 2009
U.S. locations: 1
States / cities: Miami, Florida

Conditions: Breast Cancer
Interventions: Calcitriol; Drug
Lead sponsor: University of Rochester; Other
Eligibility: 18 Years to 88 Years · Female only
Enrollment: 12 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2010 – 2021
U.S. locations: 1
States / cities: Rochester, New York

Conditions: Respiratory Infection
Interventions: High Dose Vitamin D, Standard Dose Vitamin D, Placebo, Usual Care; Drug · Dietary Supplement
Lead sponsor: University of Colorado, Denver; Other
Eligibility: 60 Years and older
Enrollment: 107 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2010 – 2016
U.S. locations: 1
States / cities: Aurora, Colorado

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: Hypovitaminosis D
Interventions: 100,000 IU cholecalciferol, Placebo; Drug
Lead sponsor: Massachusetts General Hospital; Other
Eligibility: 18 Years and older
Enrollment: 60 participants
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2013 – 2015
U.S. locations: 1
States / cities: Boston, Massachusetts

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: Gestational Diabetes
Interventions: 4000 IU vitamin D3; Drug
Lead sponsor: University of Minnesota; Other
Eligibility: 18 Years and older · Female only
Healthy volunteers: Healthy volunteers not accepted
Timeline: 2017 – 2020
U.S. locations: 1
States / cities: Minneapolis, Minnesota

Conditions: Morbid Obesity, Vitamin D Deficiency
Interventions: vitamin D3 (Replesta), vitamin D; Dietary Supplement
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

Search by objective public record fields.

A Randomized Phase IV Control Trial of Single High Dose Oral Vitamin D3 in Pediatric Patients Undergoing HSCT

The Investigation of Vitamin D and Menstrual Cycles Trial, the inVitD Trial: A Phase II Clinical Trial

Effect of Vitamin D Status and Repletion on Postoperative Total Joint Arthroplasty Complications

Vitamin D Supplementation on 15-Prostaglandin Dehydrogenase Expression in Barrett's Esophagus

Novel Combination Therapy for Osteoporosis in Men

Modulation of Breast Cancer Risk Biomarkers by High Dose Vitamin D

BioEnergetics and Metabolomics in Cystic Fibrosis

Improving Functionality in Older People

Vitamin D to Improve Outcomes by Leveraging Early Treatment

Safety and Immunologic Effect of Low Dose Versus High Dose Vitamin D3 in Multiple Sclerosis

Cholecalciferol and Calcium Carbonate in Treating Patients With Colon Cancer That Has Been Removed by Surgery

Ultra-high Dose Vitamin D for HSCT

Vitamin D and Prebiotics for Intestinal Health in Cystic Fibrosis

Study of Vitamin D in Untreated Metastatic Colorectal Cancer

The Effect of a Meal on Vitamin D Absorption

PK/PD of Vitamin D3 in Adults With CF

Safety of Vitamin D Supplementation in Older Persons

Effects of High Dose Calcitriol in Breast Cancer Patients

Vitamin D Supplementation and Acute Respiratory Infection in Older Long-Term Care Residents

Vitamin D and Arterial Stiffness in Elderly

High Dose Preoperative Cholecalciferol Supplementation and Perioperative Vitamin D Status

Pilot Study of OMEGA-3 and Vitamin D in High-Dose in Type I Diabetic Patients

High Dose Cholecalciferol to Reduce the Incidence of Gestational Diabetes in High Risk Pregnant Women

Effect of a Monthly High Dose of Vitamin D3 on Bariatric Surgery Patients