{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D3+placebo&page=2",
    "query": {
      "intervention": "Vitamin D3 placebo",
      "page": 2
    },
    "page_size": 10
  },
  "pagination": {
    "page": 2,
    "page_size": 10,
    "total_count": 410,
    "total_pages": 41,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D3+placebo&page=3&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D3+placebo&page=1&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-08T13:21:03.074Z",
  "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": "NCT01199926",
      "title": "Effect of Vitamin D Supplementation on Muscle Mass and Function",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Obesity",
        "Insulin Resistance",
        "Inflammation"
      ],
      "interventions": [
        {
          "name": "Vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG"
      ],
      "sponsor": "Purdue University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "35 Years",
        "sex": "ALL",
        "summary": "18 Years to 35 Years"
      },
      "enrollment_count": 34,
      "start_date": "2008-08",
      "completion_date": "2010-02",
      "has_results": true,
      "last_update_posted_date": "2015-05-15",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "West Lafayette, Indiana",
      "locations": [
        {
          "city": "West Lafayette",
          "state": "Indiana"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01199926"
    },
    {
      "nct_id": "NCT04536298",
      "title": "Vitamin D for COVID-19 Trial",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "COVID-19"
      ],
      "interventions": [
        {
          "name": "vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Brigham and Women's Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 2024,
      "start_date": "2020-12-28",
      "completion_date": "2024-07-01",
      "has_results": false,
      "last_update_posted_date": "2025-09-24",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04536298"
    },
    {
      "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": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "New Haven, Connecticut",
      "locations": [
        {
          "city": "New Haven",
          "state": "Connecticut"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03103750"
    },
    {
      "nct_id": "NCT03520790",
      "title": "Paricalcitol Plus Gemcitabine and Nab-paclitaxel in Metastatic Pancreatic Cancer",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Pancreatic Cancer"
      ],
      "interventions": [
        {
          "name": "Gemcitabine",
          "type": "DRUG"
        },
        {
          "name": "Nab-paclitaxel",
          "type": "DRUG"
        },
        {
          "name": "Paricalcitol",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "Dana-Farber Cancer Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 36,
      "start_date": "2018-12-05",
      "completion_date": "2024-07-01",
      "has_results": false,
      "last_update_posted_date": "2025-03-21",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 2,
      "location_summary": "Boston, Massachusetts • Philadelphia, Pennsylvania",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        },
        {
          "city": "Philadelphia",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03520790"
    },
    {
      "nct_id": "NCT01778114",
      "title": "Availability of Vitamin D in Orange Juice",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Vitamin D2 in orange juice",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Vitamin D3 in orange juice",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Vitamin D2",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "Boston University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 86,
      "start_date": "2006-12",
      "completion_date": "2007-06",
      "has_results": false,
      "last_update_posted_date": "2017-03-29",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01778114"
    },
    {
      "nct_id": "NCT02172651",
      "title": "Vitamin D in Patients With Stage I-III Colon Cancer or Resectable Colon Cancer Liver Metastases",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "EARLY_PHASE1"
      ],
      "conditions": [
        "Stage, Colon Cancer",
        "Stage I-III Colon Cancer",
        "Stage IV Colon Cancer With Resectable Liver Metastases"
      ],
      "interventions": [
        {
          "name": "Vitamin D3",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Dana-Farber Cancer Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 80,
      "start_date": "2014-07-14",
      "completion_date": "2027-06-30",
      "has_results": false,
      "last_update_posted_date": "2026-05-13",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02172651"
    },
    {
      "nct_id": "NCT01119131",
      "title": "Effects of Vitamin D in Parkinson's Disease (PD)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Parkinson Disease",
        "Accidental Falls"
      ],
      "interventions": [
        {
          "name": "Vitamin D3",
          "type": "DRUG"
        },
        {
          "name": "calcium",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "VA Office of Research and Development",
      "sponsor_class": "FED",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": "99 Years",
        "sex": "ALL",
        "summary": "50 Years to 99 Years"
      },
      "enrollment_count": 101,
      "start_date": "2011-05",
      "completion_date": "2015-01",
      "has_results": true,
      "last_update_posted_date": "2016-03-07",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Portland, Oregon",
      "locations": [
        {
          "city": "Portland",
          "state": "Oregon"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01119131"
    },
    {
      "nct_id": "NCT00692120",
      "title": "Clinical Approaches to Correcting Vitamin D Inadequacy and Maintaining Adequacy",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Vitamin D Inadequacy",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Cholecalciferol (vitamin D3)",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Ergocalciferol (vitamin D2)",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "University of Wisconsin, Madison",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 64,
      "start_date": "2007-02",
      "completion_date": "2008-11",
      "has_results": false,
      "last_update_posted_date": "2015-10-05",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Madison, Wisconsin",
      "locations": [
        {
          "city": "Madison",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00692120"
    },
    {
      "nct_id": "NCT01684722",
      "title": "Vitamin D and Omega-3 Trial to Prevent and Treat Diabetic Kidney Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Diabetes"
      ],
      "interventions": [
        {
          "name": "Vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Omega-3 fatty acids (fish oil)",
          "type": "DRUG"
        },
        {
          "name": "Vitamin D placebo",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Fish oil placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG"
      ],
      "sponsor": "University of Washington",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 1312,
      "start_date": "2010-07",
      "completion_date": "2019-11-08",
      "has_results": true,
      "last_update_posted_date": "2022-06-21",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01684722"
    },
    {
      "nct_id": "NCT01689441",
      "title": "Randomized Controlled Trial of Calcitriol vs. Placebo Among Critically-ill Patients With Sepsis",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Severe Sepsis or Septic Shock"
      ],
      "interventions": [
        {
          "name": "Calcitriol",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Brigham and Women's Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 67,
      "start_date": "2013-02",
      "completion_date": "2014-02",
      "has_results": true,
      "last_update_posted_date": "2020-11-10",
      "last_synced_at": "2026-10-08T13:21:03.074Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01689441"
    }
  ]
}