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2026 data Public-data reference. official source

Vitamin D Deficiency

Open-data reference.

47 US clinical trials · 5 currently recruiting

Active & Recent Trials

RECRUITING Phase 2 190 participants

Vitamin A Supplementation in Allogeneic Stem Cell Transplantation.

Children's Hospital Medical Center, Cincinnati

NCT06450925

RECRUITING NA 60 participants

Evaluation of the Clinical and Psychological Impact of Vitamin D Replacement in Adolescent Females at Risk for Polycystic Ovarian Syndrome (PCOS)

Yale University

NCT04355572

RECRUITING 50 participants

High Dose Interval Vitamin D Supplementation in Patients With Inflammatory Bowel Disease Receiving Biologic Therapy

Boston Children's Hospital

NCT04331639

RECRUITING NA 50 participants

Randomized Trial of Enteral Vitamin D Supplementation in Infants < 28 Weeks Gestational Age or <1000 Grams Birth Weight

The University of Texas Health Science Center, Houston

NCT05694689

RECRUITING Phase 2 50 participants

Impact of Vitamin D Supplementation on the Rate of Pathologic Complete Response in Vitamin D Deficient Patients

Wake Forest University Health Sciences

NCT04677816

ACTIVE NOT RECRUITING 9,000 participants

Emulated Study of Vitamin D Correction Vs Non-Correction

The Cooper Health System

NCT06366776

ACTIVE NOT RECRUITING Phase 4 200 participants

Preoperative Correction of Vitamin D Deficiency in Total Joint Arthroplasty (TJA)

University of Miami

NCT07006714

ACTIVE NOT RECRUITING NA 180 participants

ViDES Trial (Vitamin D Extra Supplementation)

The University of Texas Health Science Center, Houston

NCT05459298

ACTIVE NOT RECRUITING Phase 2 180 participants

High-dose Vitamin D Supplements in Older Adults

University of California, Davis

NCT03613116

ACTIVE NOT RECRUITING Phase 4 95 participants

Vitamin D Supplementation in the Prevention and Mitigation of COVID-19 Infection

Medical University of South Carolina

NCT04482673

ACTIVE NOT RECRUITING NA 60 participants

Vitamin D Sulfates in Breastmilk

Mayo Clinic

NCT06203041

ACTIVE NOT RECRUITING 40 participants

Vitamin D and Immune Mechanisms of Hypertension in Type 2 Diabetics

Washington University School of Medicine

NCT03348280

COMPLETED NA 300 participants

Effects of Vitamin D Insufficiency in Man

University of California, Los Angeles

NCT01848236

COMPLETED 240 participants

Epidemiological Analysis of Vitamin D and Breast Cancer Risk in Saudi Arabian Women

University of Arizona

NCT01817231

COMPLETED NA 225 participants

Vitamin D and Vascular Health in Children

University of Pittsburgh

NCT01797302

COMPLETED Early Phase 1 165 participants

Optimization of Blood Levels of 25(OH)-Vitamin D in African Americans

Louisiana State University Health Sciences Center Shreveport

NCT04939792

COMPLETED NA 150 participants

Optimizing Vitamin D Nutrition in Healthy Adults

Winthrop University Hospital

NCT00327847

COMPLETED NA 116 participants

Vitamin D Replacement After Kidney Transplant

University of Nebraska

NCT00748618

COMPLETED NA 112 participants

Vitamin D Oral Replacement in Asthma

IDeA States Pediatric Clinical Trials Network

NCT03686150

COMPLETED Phase 3 105 participants

Safety of Vitamin D Supplementation in Older Persons

University of Miami

NCT00681590

COMPLETED Phase 2 100 participants

Vitamin D Supplementation for Extremely Preterm Infants

University of Alabama at Birmingham

NCT01600430

COMPLETED NA 99 participants

hCAP18 Levels and Vitamin D Deficiency in Healthy Subjects

Massachusetts General Hospital

NCT00742235

COMPLETED NA 96 participants

Vitamin D Repletion in Coronary Artery Disease

Seth I. Sokol, M.D.

NCT01570309

COMPLETED NA 80 participants

Vitamin D Levels and Vitamin D Education in Geriatric Patients

University of Colorado, Denver

NCT00273611

COMPLETED Early Phase 1 80 participants

The Effect of Vitamin D Statues on Endothelial Function

University of Wisconsin, Madison

NCT01049048

COMPLETED Phase 4 79 participants

Vitamin D Increases Serum Levels of the Soluble Receptor for Advanced Glycation End Products in Women With PCOS

Maimonides Medical Center

NCT03644212

COMPLETED Phase 2 70 participants

Vitamin D for Sickle-cell Respiratory Complications

Gary M Brittenham, MD

NCT01443728

COMPLETED NA 69 participants

Evaluating the Effect of SOLIUS UV Light Source in Improving Vitamin D Status

Boston University

NCT04780776

COMPLETED NA 68 participants

Identifying Vitamin D Deficiency in Very Low Birth Weight Infant (VLBW) Infants Part 2

Medical University of South Carolina

NCT01363167

COMPLETED Phase 4 60 participants

Characterization of Hyperparathyroidism and Vitamin D Deficiency in Obesity

Weill Medical College of Cornell University

NCT00288873

COMPLETED 50 participants

Baseline Vitamin D Deficiency and COVID-19 Disease Severity

Parkview Medical Center

NCT04628000

COMPLETED 50 participants

Evaluate the Change in Iron, Vitamin D, and C-Reactive Protein Level (CRP) in a 12 to 24 Week Period

Avera McKennan Hospital & University Health Center

NCT01328704

COMPLETED Phase 4 49 participants

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

Phoenix Children's Hospital

NCT03176849

COMPLETED 45 participants

Vitamin D Deficiency and Low Bone Mineral Content in Children

University of Massachusetts, Worcester

NCT00756899

COMPLETED NA 36 participants

Effects of Vitamin D-Enriched Mushrooms on Vitamin D Status and Immune Function and Inflammatory Status in Adults

Purdue University

NCT05559112

COMPLETED NA 34 participants

Cholecalciferol (Vitamin D3) Therapy in Chronic Kidney Disease (CKD) Subjects

Atlanta VA Medical Center

NCT00427037

COMPLETED NA 31 participants

African American Children, Glycemic Control, and Type 2 Diabetes

University of Alabama at Birmingham

NCT01325987

COMPLETED Early Phase 1 25 participants

Does Supplementing Vitamin D Deficiency Affect Fusion Healing Rates in Elective Foot and Ankle Surgery?

Allegheny Singer Research Institute (also known as Allegheny Health Network Research Institute)

NCT04450199

COMPLETED NA 24 participants

Vitamin D Replacement Using Oral Thin Film (OTF) Cholecalciferol in Patients Undergoing Hematopoietic Stem Cell Transplantation

Children's Hospital Medical Center, Cincinnati

NCT04818957

COMPLETED NA 20 participants

Correlation Between Vitamin D Status and Bone Mineral Density in Patients With Hemophilia

Virginia Commonwealth University

NCT01090206

COMPLETED Phase 4 19 participants

Does Treatment of Hypovitaminosis D Increase Calcium Absorption?

University of Wisconsin, Madison

NCT00581828

COMPLETED NA 19 participants

Ultraviolet Light And Vitamin D In Subjects With Fat Malabsorption Or After Gastric Bypass Surgery

Boston University

NCT01910792

COMPLETED Phase 1 19 participants

Effect of Vitamin D Supplementation on Endothelial Function in Obese Adolescents

Mayo Clinic

NCT01746264

COMPLETED NA 18 participants

Vitamin D and Adipose Tissue Inflammation

Fred Hutchinson Cancer Center

NCT01477034

COMPLETED Phase 3 12 participants

Hepatic Dysfunction, Vitamin D Status, and Glycemic Control in Diabetes

University of Massachusetts, Worcester

NCT02132442

COMPLETED NA 6 participants

Efficacy of Vitamin D Supplementation in Obese Children

Columbia University

NCT02956408

COMPLETED NA 1 participants

Vitamin D for Muscle Metabolic Function in Cancer Cachexia

David Travis Thomas

NCT03144128

Phase Distribution

PhaseTrial count
Early Phase 1 4
Phase 2 5
Phase 3 2
Phase 4 6

Source: ClinicalTrials.gov, National Library of Medicine. Data is informational only.

Reading the Vitamin D Deficiency Trial Landscape

ClinicalTrials.gov lists 47 US studies indexed under Vitamin D Deficiency, and 5 of those are currently open to recruitment — roughly 11% of the total volume on the registry. That ratio is a useful proxy for activity level: a high share of recruiting studies often signals that research interest is current and that new enrollment opportunities are appearing, while a low share typically means the field is dominated by completed or follow-up work where most participant spots have already been filled. These counts reflect the public registry only and include studies at every stage of design, so they should be read as an index of research attention rather than as a measure of treatment availability.

The phase distribution for Vitamin D Deficiency shows 8 late-stage studies (Phase 3 and Phase 4 combined) alongside 9 earlier-phase entries (Phase 1 through Phase 2). Phase 1 and Phase 2 studies focus on early safety signals, dosing, and preliminary effect, while Phase 3 studies are typically the larger efficacy and safety trials submitted toward regulatory review, and Phase 4 studies follow approved interventions in real-world use. A condition weighted toward later phases often reflects a mature research pipeline with several interventions already close to or past approval, whereas a heavier early-phase tilt suggests the field is still exploring new mechanisms and candidate approaches.

Top sponsor activity for Vitamin D Deficiency is led by University of Massachusetts, Worcester with 2 indexed trials, alongside 9 other organizations in the top contributor list. The list on this page surfaces up to 47 of the most relevant recent and active entries, ordered with recruiting studies first so practical options are visible. All figures are derived from the public ClinicalTrials.gov dataset maintained by the National Library of Medicine and are reproduced here for reference. Inclusion of a trial, sponsor, or intervention on this page is neither an endorsement nor a recommendation — eligibility, protocol changes, and site-level status can shift frequently, so always verify current details on ClinicalTrials.gov and consult a qualified healthcare provider before acting on anything you see here.

Frequently Asked Questions

How many clinical trials are there for Vitamin D Deficiency?

PlainTrial tracks 47 US clinical trials for Vitamin D Deficiency, of which 5 are currently recruiting participants. Data sourced from ClinicalTrials.gov.

How do I find a recruiting trial for Vitamin D Deficiency?

Use the trial list above filtered by "Recruiting" status, or visit our trial finder at /recruiting to search by condition and state. Always discuss trial participation with your healthcare provider before enrolling.

Is this data current?

Data is sourced from ClinicalTrials.gov and reflects our most recent data pull. Trial status may have changed since then. Always verify current information at ClinicalTrials.gov before making decisions about participation.

Related

Data sourced from official U.S. government datasets. See our methodology for details. Retrieved and formatted by PlainTrial Editorial

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from ClinicalTrials.gov (National Library of Medicine). Consult a qualified professional before making decisions based on this data.

Source: ClinicalTrials.gov (NIH/NLM) ClinicalTrials.gov AACT registry · 2024 Trial counts and statuses sourced from ClinicalTrials.gov. Sponsor counts include both industry and federal/academic sponsors.

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