{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Placebo+%28Vitamin+C%29&page=4",
    "query": {
      "intervention": "Placebo (Vitamin C)",
      "page": 4
    },
    "page_size": 10
  },
  "pagination": {
    "page": 4,
    "page_size": 10,
    "total_count": 186,
    "total_pages": 19,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Placebo+%28Vitamin+C%29&page=5&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Placebo+%28Vitamin+C%29&page=3&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-13T08:34:59.725Z",
  "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": "NCT04437758",
      "title": "Effects of Hydrolyzed Collagen and Vitamin C on Explosive Performance",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Collagen Synthesis",
        "Rate of Force (RFD) Development"
      ],
      "interventions": [
        {
          "name": "Collagen and Vitamin C powder mix nutritional intervention",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Maltodextrin placebo powder",
          "type": "OTHER"
        },
        {
          "name": "Maximum power training exercise",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "PepsiCo Global R&D",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "30 Years",
        "sex": "MALE",
        "summary": "18 Years to 30 Years · Male only"
      },
      "enrollment_count": 50,
      "start_date": "2019-08-22",
      "completion_date": "2020-02-05",
      "has_results": false,
      "last_update_posted_date": "2020-06-18",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Davis, California",
      "locations": [
        {
          "city": "Davis",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04437758"
    },
    {
      "nct_id": "NCT07241585",
      "title": "Vitamin D Effects on Immune Microenvironment of Nonmelanoma Skin Cancer After Photodynamic Therapy (PDT)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Nonmelanoma Skin Cancer",
        "Basal Cell Carcinoma",
        "Squamous Cell Carcinoma"
      ],
      "interventions": [
        {
          "name": "Vitamin D (VitD)",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        },
        {
          "name": "Photodynamic therapy (PDT)",
          "type": "OTHER"
        },
        {
          "name": "Mohs surgery or electrodessication & curettage (ED&C) (standard of care)",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER",
        "PROCEDURE"
      ],
      "sponsor": "Case Comprehensive Cancer Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 54,
      "start_date": "2026-02-25",
      "completion_date": "2027-08",
      "has_results": false,
      "last_update_posted_date": "2026-08-18",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Cleveland, Ohio",
      "locations": [
        {
          "city": "Cleveland",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07241585"
    },
    {
      "nct_id": "NCT00133978",
      "title": "Trial of Glutamine and Antioxidant Supplementation in Critically Ill Patients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Critical Illness",
        "Sepsis",
        "Multiple Organ Failure"
      ],
      "interventions": [
        {
          "name": "Glutamine",
          "type": "OTHER"
        },
        {
          "name": "Antioxidants",
          "type": "OTHER"
        },
        {
          "name": "Glutamine + Antioxidants",
          "type": "OTHER"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "OTHER"
      ],
      "sponsor": "Daren K. Heyland",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1223,
      "start_date": "2005-04",
      "completion_date": "2012-05",
      "has_results": true,
      "last_update_posted_date": "2021-01-07",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 5,
      "location_summary": "Aurora, Colorado • Louisville, Kentucky • Dayton, Ohio + 2 more",
      "locations": [
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Louisville",
          "state": "Kentucky"
        },
        {
          "city": "Dayton",
          "state": "Ohio"
        },
        {
          "city": "Houston",
          "state": "Texas"
        },
        {
          "city": "Burlington",
          "state": "Vermont"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00133978"
    },
    {
      "nct_id": "NCT03849443",
      "title": "Single Versus Multi-Dose Oral and Intravenous Tranexamic Acid Patients at High Risk for Blood Transfusion After Spine Surgery",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "EARLY_PHASE1"
      ],
      "conditions": [
        "Open Posterior Thoracolumbar Spinal Fusion Procedure"
      ],
      "interventions": [
        {
          "name": "Tranexamic Acid Injectable Product (1000 mg intravenous bolus)",
          "type": "DRUG"
        },
        {
          "name": "Vitamin C 250 MG Oral Tablet",
          "type": "DRUG"
        },
        {
          "name": "Tranexamic Acid 650Mg Tablet",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Rush University Medical Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 604,
      "start_date": "2019-08-26",
      "completion_date": "2027-01-01",
      "has_results": false,
      "last_update_posted_date": "2026-01-08",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Chicago, Illinois",
      "locations": [
        {
          "city": "Chicago",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03849443"
    },
    {
      "nct_id": "NCT00654108",
      "title": "Safety and Immunogenicity of Peru-15-pCTB in Healthy Adult Subjects",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Gastroenteritis Escherichia Coli"
      ],
      "interventions": [
        {
          "name": "Ciprofloxacin",
          "type": "DRUG"
        },
        {
          "name": "Peru-15-pCTB",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Sodium bicarbonate/Ascorbic Acid/Aspartame Buffer",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "45 Years",
        "sex": "ALL",
        "summary": "18 Years to 45 Years"
      },
      "enrollment_count": 62,
      "start_date": "2008-06-02",
      "completion_date": "2010-12-31",
      "has_results": false,
      "last_update_posted_date": "2021-07-29",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Cincinnati, Ohio",
      "locations": [
        {
          "city": "Cincinnati",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00654108"
    },
    {
      "nct_id": "NCT00490412",
      "title": "Vitamin D Reabsorption in Adolescents and Young Adults With HIV Infection",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "HIV Infections"
      ],
      "interventions": [
        {
          "name": "Vitamin D supplement",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "University of North Carolina, Chapel Hill",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "24 Years",
        "sex": "ALL",
        "summary": "18 Years to 24 Years"
      },
      "enrollment_count": 207,
      "start_date": "2007-12",
      "completion_date": "2010-01",
      "has_results": false,
      "last_update_posted_date": "2017-02-28",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 14,
      "location_summary": "Los Angeles, California • San Francisco, California • Washington D.C., District of Columbia + 10 more",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        },
        {
          "city": "Fort Lauderdale",
          "state": "Florida"
        },
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00490412"
    },
    {
      "nct_id": "NCT06544915",
      "title": "Evaluating the Effects of a Synbiotic Versus Probiotic or Placebo on Gut Microbiota and Cardiometabolic Health: A Randomized Double-Blind Placebo Controlled Trial",
      "overall_status": "UNKNOWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Blood Pressure, Body Composition, Immune Function"
      ],
      "interventions": [
        {
          "name": "Synbiotic, Probiotic, Placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Skidmore College",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "60 Years",
        "sex": "ALL",
        "summary": "18 Years to 60 Years"
      },
      "enrollment_count": 60,
      "start_date": "2024-07-23",
      "completion_date": "2025-01-01",
      "has_results": false,
      "last_update_posted_date": "2024-08-09",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Saratoga Springs, New York",
      "locations": [
        {
          "city": "Saratoga Springs",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06544915"
    },
    {
      "nct_id": "NCT05332717",
      "title": "TKA Melatonin and Sleep Quality",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Arthroplasty",
        "Replacement",
        "Knee",
        "Sleep Initiation and Maintenance Disorders"
      ],
      "interventions": [
        {
          "name": "Melatonin 5 mg",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo (Vitamin C)",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Hospital for Special Surgery, New York",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 176,
      "start_date": "2022-01-10",
      "completion_date": "2022-04-30",
      "has_results": false,
      "last_update_posted_date": "2023-09-14",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "New York, New York",
      "locations": [
        {
          "city": "New York",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05332717"
    },
    {
      "nct_id": "NCT05908825",
      "title": "Placebo-Controlled Study Assessing the Use of a Novel Exfoliative Serum With A Chemical Peel to Improve Photodamage in Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Photodamaged Skin"
      ],
      "interventions": [
        {
          "name": "Vitamin C with AHA Exfoliative Serum",
          "type": "DRUG"
        },
        {
          "name": "Placebo serum",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Austin Institute for Clinical Research",
      "sponsor_class": "NETWORK",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": "65 Years",
        "sex": "FEMALE",
        "summary": "30 Years to 65 Years · Female only"
      },
      "enrollment_count": 34,
      "start_date": "2023-06-22",
      "completion_date": "2024-01-26",
      "has_results": false,
      "last_update_posted_date": "2024-07-19",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Pflugerville, Texas",
      "locations": [
        {
          "city": "Pflugerville",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05908825"
    },
    {
      "nct_id": "NCT01595516",
      "title": "Nebivolol and Endothelial Regulation of Fibrinolysis (NERF)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Prehypertension",
        "Hypertension"
      ],
      "interventions": [
        {
          "name": "Nebivolol",
          "type": "DRUG"
        },
        {
          "name": "Metoprolol",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        },
        {
          "name": "Bradykinin",
          "type": "OTHER"
        },
        {
          "name": "Saline",
          "type": "OTHER"
        },
        {
          "name": "Vitamin C",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "University of Colorado, Boulder",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "45 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "45 Years to 65 Years"
      },
      "enrollment_count": 44,
      "start_date": "2012-02",
      "completion_date": "2017-10",
      "has_results": true,
      "last_update_posted_date": "2019-06-25",
      "last_synced_at": "2026-10-13T08:34:59.725Z",
      "location_count": 1,
      "location_summary": "Boulder, Colorado",
      "locations": [
        {
          "city": "Boulder",
          "state": "Colorado"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01595516"
    }
  ]
}