{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=High+dose+vitamin+D3",
    "query": {
      "intervention": "High dose vitamin D3"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 120,
    "total_pages": 12,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=High+dose+vitamin+D3&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-21T08:09:25.117Z",
  "attribution": "Data derived from public ClinicalTrials.gov records. The official record at https://clinicaltrials.gov/ remains the source of truth for current availability, contacts, and full study details.",
  "notes": [
    "This endpoint exposes only public summary fields — no participant contact emails, phone numbers, or scraped investigator contact details.",
    "For contact information and full protocol detail, follow each trial's `official_url` to the ClinicalTrials.gov record.",
    "This API is a navigational aid. It does not provide medical advice, eligibility determinations, or compensation guarantees."
  ],
  "trials": [
    {
      "nct_id": "NCT01593501",
      "title": "How Does Magnesium Status Influence Calcium Homeostasis?",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Magnesium Deficiency",
        "Calcium Metabolism Disorders"
      ],
      "interventions": [
        {
          "name": "vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "University of Wisconsin, Madison",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": "75 Years",
        "sex": "FEMALE",
        "summary": "30 Years to 75 Years · Female only"
      },
      "enrollment_count": 39,
      "start_date": "2012-05",
      "completion_date": "2014-08",
      "has_results": false,
      "last_update_posted_date": "2016-11-01",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Madison, Wisconsin",
      "locations": [
        {
          "city": "Madison",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01593501"
    },
    {
      "nct_id": "NCT03649802",
      "title": "Vitamin D and Arterial Stiffness in Elderly",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Vitamin D Deficiency",
        "Arterial Stiffness"
      ],
      "interventions": [
        {
          "name": "Low dose vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "High dose vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Texas Tech University Health Sciences Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": "89 Years",
        "sex": "ALL",
        "summary": "65 Years to 89 Years"
      },
      "enrollment_count": 52,
      "start_date": "2018-08-16",
      "completion_date": "2021-12-31",
      "has_results": false,
      "last_update_posted_date": "2022-03-21",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Lubbock, Texas",
      "locations": [
        {
          "city": "Lubbock",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03649802"
    },
    {
      "nct_id": "NCT03176849",
      "title": "A Randomized Phase IV Control Trial of Single High Dose Oral Vitamin D3 in Pediatric Patients Undergoing HSCT",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "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": [
        {
          "name": "Vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Standard Vitamin D3 Supplementation",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Phoenix Children's Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "1 Year",
        "maximum_age": "25 Years",
        "sex": "ALL",
        "summary": "1 Year to 25 Years"
      },
      "enrollment_count": 49,
      "start_date": "2017-11-01",
      "completion_date": "2019-07-01",
      "has_results": false,
      "last_update_posted_date": "2020-11-17",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Phoenix, Arizona",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03176849"
    },
    {
      "nct_id": "NCT01425476",
      "title": "Changes in Breast Cancer Biomarkers Using Synergistic Prostaglandin Inhibitors",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Celecoxib",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        },
        {
          "name": "Cholecalciferol",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Hartford Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 45,
      "start_date": "2008-07",
      "completion_date": "2016-11",
      "has_results": false,
      "last_update_posted_date": "2017-08-09",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Grand Forks, North Dakota",
      "locations": [
        {
          "city": "Grand Forks",
          "state": "North Dakota"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01425476"
    },
    {
      "nct_id": "NCT01561989",
      "title": "Cholecalciferol and Flu Vaccine in Treating Healthy Participants",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Healthy, no Evidence of Disease"
      ],
      "interventions": [
        {
          "name": "cholecalciferol",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "questionnaire administration",
          "type": "OTHER"
        },
        {
          "name": "trivalent influenza vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER",
        "BIOLOGICAL"
      ],
      "sponsor": "Roswell Park Cancer Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "64 Years",
        "sex": "ALL",
        "summary": "18 Years to 64 Years"
      },
      "enrollment_count": 11,
      "start_date": "2011-10",
      "completion_date": "2015-06",
      "has_results": true,
      "last_update_posted_date": "2020-03-10",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Buffalo, New York",
      "locations": [
        {
          "city": "Buffalo",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01561989"
    },
    {
      "nct_id": "NCT05009498",
      "title": "Vitamin D3 Supplementation for Vitamin D Deficiency in Rotator Cuff Repair Surgery",
      "overall_status": "UNKNOWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Vitamin D Deficiency",
        "Rotator Cuff Tears"
      ],
      "interventions": [
        {
          "name": "Vitamin D3 supplementation",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "Community Memorial Health System",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "18 Years to 65 Years"
      },
      "enrollment_count": 240,
      "start_date": "2021-09-01",
      "completion_date": "2024-08-01",
      "has_results": false,
      "last_update_posted_date": "2021-08-17",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 2,
      "location_summary": "Ventura, California",
      "locations": [
        {
          "city": "Ventura",
          "state": "California"
        },
        {
          "city": "Ventura",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05009498"
    },
    {
      "nct_id": "NCT01024777",
      "title": "Safety and Immunologic Effect of Low Dose Versus High Dose Vitamin D3 in Multiple Sclerosis",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Multiple Sclerosis",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Cholecalciferol",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Johns Hopkins University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "55 Years",
        "sex": "ALL",
        "summary": "18 Years to 55 Years"
      },
      "enrollment_count": 40,
      "start_date": "2010-03",
      "completion_date": "2013-01",
      "has_results": false,
      "last_update_posted_date": "2013-02-06",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Baltimore, Maryland",
      "locations": [
        {
          "city": "Baltimore",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01024777"
    },
    {
      "nct_id": "NCT01337635",
      "title": "Vitamin D Deficiency and Atopic Dermatitis",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Atopic Dermatitis",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Vitamin D",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Medical College of Wisconsin",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "1 Year",
        "maximum_age": "18 Years",
        "sex": "ALL",
        "summary": "1 Year to 18 Years"
      },
      "enrollment_count": 7,
      "start_date": "2010-11",
      "completion_date": "2013-04",
      "has_results": true,
      "last_update_posted_date": "2018-12-05",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "Milwaukee, Wisconsin",
      "locations": [
        {
          "city": "Milwaukee",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01337635"
    },
    {
      "nct_id": "NCT03103750",
      "title": "Vitamin D as a Therapeutic Adjunct in the Stimulant Treatment of ADHD",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "ADHD"
      ],
      "interventions": [
        {
          "name": "Magnetic Resonance Imaging (MRI)",
          "type": "PROCEDURE"
        },
        {
          "name": "PHNO",
          "type": "DRUG"
        },
        {
          "name": "calcitriol",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo oral capsule",
          "type": "DRUG"
        },
        {
          "name": "high-resolution research tomography",
          "type": "PROCEDURE"
        },
        {
          "name": "Dextro Amphetamine",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "PROCEDURE",
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Yale University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "18 Years to 50 Years"
      },
      "enrollment_count": 24,
      "start_date": "2017-08-15",
      "completion_date": "2023-01-17",
      "has_results": true,
      "last_update_posted_date": "2024-03-19",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 1,
      "location_summary": "New Haven, Connecticut",
      "locations": [
        {
          "city": "New Haven",
          "state": "Connecticut"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03103750"
    },
    {
      "nct_id": "NCT02138838",
      "title": "Efficacy and Safety of Cinacalcet in Pediatric Patients With Secondary Hyperparathyroidism (SHPT) and Chronic Kidney Disease (CKD) on Dialysis",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Chronic Kidney Disease, Secondary Hyperparathyroidism"
      ],
      "interventions": [
        {
          "name": "Cinacalcet HCl",
          "type": "DRUG"
        },
        {
          "name": "Standard of Care",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Amgen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "6 Years",
        "maximum_age": "17 Years",
        "sex": "ALL",
        "summary": "6 Years to 17 Years"
      },
      "enrollment_count": 55,
      "start_date": "2014-11-07",
      "completion_date": "2016-06-23",
      "has_results": true,
      "last_update_posted_date": "2020-06-29",
      "last_synced_at": "2026-09-21T08:09:25.117Z",
      "location_count": 26,
      "location_summary": "Los Angeles, California • Wilmington, Delaware • Atlanta, Georgia + 22 more",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Wilmington",
          "state": "Delaware"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Chicago",
          "state": "Illinois"
        },
        {
          "city": "Iowa City",
          "state": "Iowa"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02138838"
    }
  ]
}