Medical Information Only. Consult your healthcare provider before considering clinical trial enrollment.

ClinicalTrials.gov 5 recruiting now full pipeline

Vitamin D Deficiency: full-pipeline trial registry

5 of 49 indexed Vitamin D Deficiency trials are currently recruiting.

Corpus placement: #281 of 28,707 conditions by registered trial count.

49 US clinical trials · 5 currently recruiting · #281 of 28,707 conditions by registered trial count

Vitamin D Deficiency: 49 US clinical trials tracked, 5 recruiting.

Vitamin D Deficiency is the subject of 49 registered US clinical trials on ClinicalTrials.gov, 5 of them currently open to new participants. 9 are in Phase 3-4 (later-stage) and 10 in Phase 1-2 (earlier-stage). The most active sponsor is University of Massachusetts, Worcester, running 2 of these trials.

Enrollment posture brief

Registry condition vitamin-d-deficiency

OPEN 5 | RECR 10% | LATE 9 | EARLY 10 | RANK #281 | SPON 2

Nearest open-share peer: Angina Pectoris (10% recruiting · 10 trials)

Diet, Healthy49%Duchenne Muscular Dystrophy44.9%Chronic Disease36.7%Arthritis30.6%Vitamin D Deficiency (this)10%
Open-enrollment share among volume-matched conditions near Vitamin D Deficiency

Vitamin D Deficiency lists 5 open slots (10% of 49 indexed trials). Peers are matched on registered volume, not therapeutic-area browse lists. How peer matching works →

Key findings

What ClinicalTrials.gov does not surface for Vitamin D Deficiency on its own pages , computed from the registry mirror as of 2026-08-08. Each line carries its own denominator so it can be quoted as it stands.

  1. Vitamin D Deficiency is recruiting below its size-band peers.

    5 of 49 indexed trials (10.2%) are open to enrollment, against a 39.7% average across 762 conditions with 20-99 trials. The peer set uses the same ClinicalTrials.gov-derived counts as this page.

  2. Sponsorship of Vitamin D Deficiency trials is spread across many organizations.

    University of Massachusetts, Worcester accounts for 2 of 49 trials (4.1%). 40 distinct sponsors appear on at least one study for this condition label.

  3. Most Vitamin D Deficiency trials plan to enrol fewer than 100 people.

    Median target enrolment is 68 among the 49 trials that report a genuine target (sentinel values excluded). 33 of those (67.3%) plan for fewer than 100 participants.

  4. Vitamin D Deficiency research is mostly interventional.

    42 interventional and 7 observational studies make up this index (85.7% interventional). Study type is sponsor-reported on ClinicalTrials.gov.

Phase 14Phase 26Phase 33Phase 46

Open and recent trials

49 total, page 1 of 1

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 Phase 2 274 participants

Hypovitaminosis D in Neurocritical Patients

University of Utah

NCT02881957

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 Phase 3 130 participants

Vitamin D in Vulnerable Adults (VIVA-VA)

VA Office of Research and Development

NCT01170273

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
Phase 1 4
Phase 2 6
Phase 3 3
Phase 4 6

Named interventions

Most-linked intervention names on Vitamin D Deficiency records (sponsor-reported on ClinicalTrials.gov). Counts are trial links, not unique products.

Vitamin D3 Dietary supplement
9 trials
Placebo Dietary supplement
5 trials
Cholecalciferol Drug
3 trials
Placebo Other
3 trials
Placebo Drug
3 trials
Sugar pill Other
2 trials
Vitamin D2 Dietary supplement
2 trials
Vitamin D Drug
2 trials

US sites by state

Facility locations filed on Vitamin D Deficiency trials. A trial with sites in several states counts in each.

New York 7 trials
Massachusetts 6 trials
Florida 4 trials
South Carolina 3 trials
Wisconsin 2 trials
Texas 2 trials
Pennsylvania 2 trials
Ohio 2 trials

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

What to do with this Vitamin D Deficiency page

49 registered trials, 5 currently recruiting, is a starting point for a conversation, not a diagnosis or a recommendation.

Trial and recruiting counts reflect ClinicalTrials.gov registry status as of the data vintage above; individual trial eligibility and enrollment status can change.

Every figure on PlainTrial is rendered directly from the ClinicalTrials.gov registry, no number is typed in by an editor. This Vitamin D Deficiency condition card totals 49 registered trials; most-linked intervention Vitamin D3; top US site state New York. See our editorial standards & corrections policy, the methodology behind these numbers, the data changelog, or report a data error.