{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D+Placebo&page=3",
    "query": {
      "intervention": "Vitamin D Placebo",
      "page": 3
    },
    "page_size": 10
  },
  "pagination": {
    "page": 3,
    "page_size": 10,
    "total_count": 437,
    "total_pages": 44,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D+Placebo&page=4&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D+Placebo&page=2&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-10T14:20:39.220Z",
  "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": "NCT05838716",
      "title": "Vitamin D for Prostate Endocrine Therapy",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Stage I Prostate Cancer AJCC v8",
        "Stage II Prostate Cancer AJCC v8",
        "Stage III Prostate Cancer AJCC v8",
        "Stage IVA Prostate Cancer AJCC v8"
      ],
      "interventions": [
        {
          "name": "Biospecimen Collection",
          "type": "PROCEDURE"
        },
        {
          "name": "D Vitamin",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Dual X-ray Absorptiometry",
          "type": "PROCEDURE"
        },
        {
          "name": "Placebo Administration",
          "type": "DRUG"
        },
        {
          "name": "Quality-of-Life Assessment",
          "type": "OTHER"
        },
        {
          "name": "Questionnaire Administration",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "PROCEDURE",
        "DIETARY_SUPPLEMENT",
        "DRUG",
        "OTHER"
      ],
      "sponsor": "University of Rochester",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "MALE",
        "summary": "50 Years and older · Male only"
      },
      "enrollment_count": 240,
      "start_date": "2023-12-14",
      "completion_date": "2029-04-29",
      "has_results": false,
      "last_update_posted_date": "2026-01-15",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 51,
      "location_summary": "Newark, Delaware • Danville, Illinois • Decatur, Illinois + 39 more",
      "locations": [
        {
          "city": "Newark",
          "state": "Delaware"
        },
        {
          "city": "Newark",
          "state": "Delaware"
        },
        {
          "city": "Danville",
          "state": "Illinois"
        },
        {
          "city": "Decatur",
          "state": "Illinois"
        },
        {
          "city": "Effingham",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05838716"
    },
    {
      "nct_id": "NCT01691833",
      "title": "The Effect of Hypovitaminosis D and Vitamin D Supplementation on Fracture Nonunion Rates",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Hypovitaminosis D"
      ],
      "interventions": [
        {
          "name": "Vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Wake Forest University Health Sciences",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 113,
      "start_date": "2011-02",
      "completion_date": "2017-12",
      "has_results": true,
      "last_update_posted_date": "2022-07-14",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 1,
      "location_summary": "Charlotte, North Carolina",
      "locations": [
        {
          "city": "Charlotte",
          "state": "North Carolina"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01691833"
    },
    {
      "nct_id": "NCT05533658",
      "title": "The Effects of VisionPure™ on Indices of Vision Health and Cognitive Function",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Eye Health",
        "Vision",
        "Cognitive Function"
      ],
      "interventions": [
        {
          "name": "VisionPure Dietary Supplement",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Applied Science & Performance Institute",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "40 Years",
        "sex": "ALL",
        "summary": "18 Years to 40 Years"
      },
      "enrollment_count": 15,
      "start_date": "2022-08-01",
      "completion_date": "2023-02-03",
      "has_results": false,
      "last_update_posted_date": "2023-05-26",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 3,
      "location_summary": "Lutz, Florida • Tampa, Florida",
      "locations": [
        {
          "city": "Lutz",
          "state": "Florida"
        },
        {
          "city": "Tampa",
          "state": "Florida"
        },
        {
          "city": "Tampa",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05533658"
    },
    {
      "nct_id": "NCT01617109",
      "title": "Optimizing Vitamin D Status During Initial Military Training",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Bone Health",
        "Nutrition Status"
      ],
      "interventions": [
        {
          "name": "Ca/Vit D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "United States Army Research Institute of Environmental Medicine",
      "sponsor_class": "FED",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "17 Years",
        "maximum_age": "42 Years",
        "sex": "ALL",
        "summary": "17 Years to 42 Years"
      },
      "enrollment_count": 342,
      "start_date": "2012-06",
      "completion_date": "2018-05-02",
      "has_results": false,
      "last_update_posted_date": "2018-10-11",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 2,
      "location_summary": "Fort Sill, Oklahoma • San Antonio, Texas",
      "locations": [
        {
          "city": "Fort Sill",
          "state": "Oklahoma"
        },
        {
          "city": "San Antonio",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01617109"
    },
    {
      "nct_id": "NCT02877641",
      "title": "Cholecalciferol Supplementation in Strengthening Inspiratory Muscles in Cholecalciferol-Deficient Patients With Chronic Obstructive Pulmonary Disease",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Chronic Obstructive Pulmonary Disease",
        "Muscle Weakness"
      ],
      "interventions": [
        {
          "name": "Cholecalciferol",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Laboratory Biomarker Analysis",
          "type": "OTHER"
        },
        {
          "name": "Multivitamin",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        },
        {
          "name": "Questionnaire Administration",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "Roswell Park Cancer Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 4,
      "start_date": "2014-04-16",
      "completion_date": "2017-02-01",
      "has_results": false,
      "last_update_posted_date": "2017-02-15",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 1,
      "location_summary": "Buffalo, New York",
      "locations": [
        {
          "city": "Buffalo",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02877641"
    },
    {
      "nct_id": "NCT03602261",
      "title": "Safety, Efficacy, PK and PD of CTAP101 (Calcifediol) ER Capsules for SHPT in HD Patients VDI",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Secondary Hyperparathyroidism Due to Renal Causes",
        "Chronic Kidney Diseases",
        "Vitamin D Deficiency",
        "Stage 5 Chronic Kidney Disease"
      ],
      "interventions": [
        {
          "name": "Calcifediol Oral Capsule",
          "type": "DRUG"
        },
        {
          "name": "Placebo oral capsule",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "OPKO Health, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 44,
      "start_date": "2018-07-09",
      "completion_date": "2021-02-24",
      "has_results": true,
      "last_update_posted_date": "2026-04-03",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 18,
      "location_summary": "Peoria, Arizona • Phoenix, Arizona • Cypress, California + 13 more",
      "locations": [
        {
          "city": "Peoria",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Cypress",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03602261"
    },
    {
      "nct_id": "NCT06911073",
      "title": "A Study to Evaluate a Postbiotic in Supporting Weight Loss and Metabolic Health",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Obesity and Overweight"
      ],
      "interventions": [
        {
          "name": "Postbiotic",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "ResBiotic Nutrition, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "18 Years to 65 Years"
      },
      "enrollment_count": 80,
      "start_date": "2025-05-02",
      "completion_date": "2026-03-01",
      "has_results": false,
      "last_update_posted_date": "2026-08-14",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 1,
      "location_summary": "Birmingham, Alabama",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06911073"
    },
    {
      "nct_id": "NCT01942694",
      "title": "Vitamin D and Type 2 Diabetes Study",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Prediabetes",
        "Type 2 Diabetes"
      ],
      "interventions": [
        {
          "name": "Vitamin D (Cholecalciferol)",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "Tufts Medical Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "30 Years and older"
      },
      "enrollment_count": 2423,
      "start_date": "2013-10",
      "completion_date": "2018-11",
      "has_results": true,
      "last_update_posted_date": "2022-08-16",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 25,
      "location_summary": "Phoenix, Arizona • Los Angeles, California • Palo Alto, California + 20 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Palo Alto",
          "state": "California"
        },
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Orlando",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01942694"
    },
    {
      "nct_id": "NCT00996866",
      "title": "Vitamin D Supplementation Requirement in Obese Subjects",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Vitamin D3",
          "type": "DRUG"
        },
        {
          "name": "placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Winthrop University Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "70 Years",
        "sex": "ALL",
        "summary": "18 Years to 70 Years"
      },
      "enrollment_count": 27,
      "start_date": "2008-12",
      "completion_date": "2013-08",
      "has_results": true,
      "last_update_posted_date": "2023-07-03",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 1,
      "location_summary": "Mineola, New York",
      "locations": [
        {
          "city": "Mineola",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00996866"
    },
    {
      "nct_id": "NCT00889629",
      "title": "Pilot Study Evaluating Doxercalciferol Replacement Therapy in Kidney Transplant Recipients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Chronic Kidney Disease",
        "Kidney Transplantation"
      ],
      "interventions": [
        {
          "name": "Doxercalciferol",
          "type": "DRUG"
        },
        {
          "name": "placebo",
          "type": "DRUG"
        },
        {
          "name": "25-OH Vitamin D3",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Mariana Markell",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "18 Years to 65 Years"
      },
      "enrollment_count": 39,
      "start_date": "2008-11",
      "completion_date": "2010-01",
      "has_results": false,
      "last_update_posted_date": "2019-02-22",
      "last_synced_at": "2026-10-10T14:20:39.220Z",
      "location_count": 1,
      "location_summary": "Brooklyn, New York",
      "locations": [
        {
          "city": "Brooklyn",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00889629"
    }
  ]
}