{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+influenza+vaccine%2C+standard+dose",
    "query": {
      "intervention": "Quadrivalent influenza vaccine, standard dose"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 31,
    "total_pages": 4,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+influenza+vaccine%2C+standard+dose&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-07T19:05:21.736Z",
  "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": "NCT04544267",
      "title": "Study on a High-Dose Quadrivalent Influenza Vaccine Compared With Standard-Dose Quadrivalent Influenza Vaccine in Children 6 Months Through 35 Months of Age",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Quadrivalent influenza vaccine, high-dose",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent influenza vaccine, standard dose",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Sanofi Pasteur, a Sanofi Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "6 Months",
        "maximum_age": "35 Months",
        "sex": "ALL",
        "summary": "6 Months to 35 Months"
      },
      "enrollment_count": 100,
      "start_date": "2020-09-15",
      "completion_date": "2021-06-02",
      "has_results": true,
      "last_update_posted_date": "2025-12-24",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 10,
      "location_summary": "San Diego, California • Miami, Florida • Atlanta, Georgia + 6 more",
      "locations": [
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Miami",
          "state": "Florida"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "El Dorado",
          "state": "Kansas"
        },
        {
          "city": "Bardstown",
          "state": "Kentucky"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04544267"
    },
    {
      "nct_id": "NCT05553301",
      "title": "Safety and Immunogenicity of Quadrivalent Influenza mRNA Vaccine MRT5407 in Adult Participants18 Years of Age and Older",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Influenza Immunization"
      ],
      "interventions": [
        {
          "name": "Quadrivalent Influenza mRNA Vaccine MRT5407",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Recombinant Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza Standard Dose Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza High-Dose Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Sanofi Pasteur, a Sanofi Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 560,
      "start_date": "2022-10-03",
      "completion_date": "2024-01-19",
      "has_results": false,
      "last_update_posted_date": "2025-01-24",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 23,
      "location_summary": "Rolling Hills Estates, California • San Diego, California • DeLand, Florida + 16 more",
      "locations": [
        {
          "city": "Rolling Hills Estates",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "DeLand",
          "state": "Florida"
        },
        {
          "city": "Gainesville",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05553301"
    },
    {
      "nct_id": "NCT02860039",
      "title": "High Dose Flu Vaccine in Treating Children Who Have Undergone Donor Stem Cell Transplant",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Hematopoietic Cell Transplantation Recipient",
        "Malignant Neoplasm",
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Trivalent Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Laboratory Biomarker Analysis",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "Vanderbilt-Ingram Cancer Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "3 Years",
        "maximum_age": "17 Years",
        "sex": "ALL",
        "summary": "3 Years to 17 Years"
      },
      "enrollment_count": 170,
      "start_date": "2016-09",
      "completion_date": "2024-09",
      "has_results": true,
      "last_update_posted_date": "2024-10-22",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 9,
      "location_summary": "San Francisco, California • Kansas City, Missouri • Cincinnati, Ohio + 6 more",
      "locations": [
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Kansas City",
          "state": "Missouri"
        },
        {
          "city": "Cincinnati",
          "state": "Ohio"
        },
        {
          "city": "Columbus",
          "state": "Ohio"
        },
        {
          "city": "Philadelphia",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02860039"
    },
    {
      "nct_id": "NCT02500680",
      "title": "The Safety, Tolerance, and Immunogenicity of MAS-1-Adjuvanted Seasonal Inactivated Influenza Vaccine (MER4101)",
      "overall_status": "UNKNOWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Influenza, Human"
      ],
      "interventions": [
        {
          "name": "MER4101",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Nova Immunotherapeutics Limited",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 102,
      "start_date": "2015-07",
      "completion_date": "2020-12",
      "has_results": false,
      "last_update_posted_date": "2019-09-06",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 1,
      "location_summary": "St Louis, Missouri",
      "locations": [
        {
          "city": "St Louis",
          "state": "Missouri"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02500680"
    },
    {
      "nct_id": "NCT06229392",
      "title": "A Study to Evaluate the Intratumoral Influenza Vaccine Administration in Patients With Breast Cancer",
      "overall_status": "WITHDRAWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Breast Cancer",
        "Breast Cancer Triple Negative"
      ],
      "interventions": [
        {
          "name": "Fluzone Quadrivalent",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "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": 0,
      "start_date": "2026-06-01",
      "completion_date": "2027-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-03-11",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 1,
      "location_summary": "Chicago, Illinois",
      "locations": [
        {
          "city": "Chicago",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06229392"
    },
    {
      "nct_id": "NCT03598439",
      "title": "Randomized Influenza Vaccine Evaluation of Immune Response",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Standard IIV4",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Recombinant",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Cell-culture",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Marshfield Clinic Research Foundation",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "64 Years",
        "sex": "ALL",
        "summary": "18 Years to 64 Years"
      },
      "enrollment_count": 366,
      "start_date": "2018-07-30",
      "completion_date": "2024-07-09",
      "has_results": false,
      "last_update_posted_date": "2025-11-21",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 1,
      "location_summary": "Marshfield, Wisconsin",
      "locations": [
        {
          "city": "Marshfield",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03598439"
    },
    {
      "nct_id": "NCT05501561",
      "title": "Safety and Immunogenicity of Different Formulations of an MF59-Adjuvanted Influenza Vaccine in Older Adults ≥50 Years of Age",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Influenza, Human"
      ],
      "interventions": [
        {
          "name": "Experimental: IIV-A Investigational IIV-A administered as a single dose intramuscularly on Day 1",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Experimental: aIIV-B Investigational aIIV-B administered as a single dose intramuscularly on Day 1",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Experimental: aIIV-C Investigational aIIV-C administered as a single dose intramuscularly on Day 1",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Active Comparator: Licensed IIV IIV administered as a single dose intramuscularly on Day 1",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Seqirus",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 1056,
      "start_date": "2022-08-25",
      "completion_date": "2023-03-31",
      "has_results": true,
      "last_update_posted_date": "2026-06-30",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 47,
      "location_summary": "Tempe, Arizona • Huntington Beach, California • San Diego, California + 42 more",
      "locations": [
        {
          "city": "Tempe",
          "state": "Arizona"
        },
        {
          "city": "Huntington Beach",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Colorado Springs",
          "state": "Colorado"
        },
        {
          "city": "Milford",
          "state": "Connecticut"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05501561"
    },
    {
      "nct_id": "NCT03346772",
      "title": "Study of Immune Responses to Influenza Vaccination",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza Vaccination"
      ],
      "interventions": [
        {
          "name": "Influenza vaccination",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "University of Pennsylvania",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 150,
      "start_date": "2017-10-20",
      "completion_date": "2026-07-01",
      "has_results": false,
      "last_update_posted_date": "2026-08-27",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 1,
      "location_summary": "Philadelphia, Pennsylvania",
      "locations": [
        {
          "city": "Philadelphia",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03346772"
    },
    {
      "nct_id": "NCT03845231",
      "title": "Mucosal and Systemic Immunity After Viral Challenge of Healthy Volunteers Vaccinated With Inactivated Influenza Vaccine Via the Intranasal Versus Intramuscular Route",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Flucelvax(R)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Human Challenge virus",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "55 Years",
        "sex": "ALL",
        "summary": "18 Years to 55 Years"
      },
      "enrollment_count": 82,
      "start_date": "2019-04-29",
      "completion_date": "2020-10-28",
      "has_results": false,
      "last_update_posted_date": "2020-11-10",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 1,
      "location_summary": "Bethesda, Maryland",
      "locations": [
        {
          "city": "Bethesda",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03845231"
    },
    {
      "nct_id": "NCT03743688",
      "title": "Kinetics of the Immune Response to Inactivated Influenza Vaccine in Healthy Adults",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Influenza",
        "Influenza, Human",
        "Vaccine Reaction",
        "Influenza A",
        "Influenza Type B",
        "Influenza A H1N1",
        "Influenza A H3N2"
      ],
      "interventions": [
        {
          "name": "Influenza Vaccine Recipients",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Vanderbilt University Medical Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "45 Years",
        "sex": "ALL",
        "summary": "18 Years to 45 Years"
      },
      "enrollment_count": 10,
      "start_date": "2018-12-04",
      "completion_date": "2019-07-26",
      "has_results": false,
      "last_update_posted_date": "2019-08-05",
      "last_synced_at": "2026-10-07T19:05:21.736Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03743688"
    }
  ]
}