{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+seasonal+influenza+vaccine",
    "query": {
      "intervention": "Quadrivalent seasonal influenza vaccine"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 61,
    "total_pages": 7,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+seasonal+influenza+vaccine&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-11T16:17:41.142Z",
  "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": "NCT03438487",
      "title": "Flucelvax (TIVc or QIVc) Pregnancy Registry",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Influenza, Human",
        "Pregnancy",
        "Birth Defect"
      ],
      "interventions": [
        {
          "name": "Flucelvax Trivalent Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Flucelvax Quadrivalent Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Seqirus",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "Female only"
      },
      "enrollment_count": 692,
      "start_date": "2017-09-01",
      "completion_date": "2020-12-31",
      "has_results": false,
      "last_update_posted_date": "2022-11-04",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 1,
      "location_summary": "Wilmington, North Carolina",
      "locations": [
        {
          "city": "Wilmington",
          "state": "North Carolina"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03438487"
    },
    {
      "nct_id": "NCT02233816",
      "title": "Immunogenicity, Safety and Tolerability of a Plant-Derived Seasonal Virus-Like-Particle Quadrivalent Influenza Vaccine in Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Virus Diseases",
        "RNA Virus Infections",
        "Respiratory Tract Diseases",
        "Respiratory Tract Infections"
      ],
      "interventions": [
        {
          "name": "Low dose of quadrivalent VLP vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Medium dose of quadrivalent VLP vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High dose of quadrivalent VLP vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Medicago",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "49 Years",
        "sex": "ALL",
        "summary": "18 Years to 49 Years"
      },
      "enrollment_count": 300,
      "start_date": "2014-07-28",
      "completion_date": "2015-06-22",
      "has_results": false,
      "last_update_posted_date": "2019-11-13",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 2,
      "location_summary": "Hollywood, Florida • Miami, Florida",
      "locations": [
        {
          "city": "Hollywood",
          "state": "Florida"
        },
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02233816"
    },
    {
      "nct_id": "NCT01991587",
      "title": "Safety, Tolerability and Immunogenicity of a Plant-made Seasonal Quadrivalent VLP Influenza Vaccine in Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Virus Diseases",
        "RNA Virus Infections",
        "Respiratory Tract Diseases",
        "Respiratory Tract Infections"
      ],
      "interventions": [
        {
          "name": "Low dose of quadrivalent VLP vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Medium dose of quadrivalent VLP vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High dose of quadrivalent VLP vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Medicago",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "49 Years",
        "sex": "ALL",
        "summary": "18 Years to 49 Years"
      },
      "enrollment_count": 120,
      "start_date": "2013-10-08",
      "completion_date": "2014-06-30",
      "has_results": false,
      "last_update_posted_date": "2020-06-11",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 1,
      "location_summary": "Miami, Florida",
      "locations": [
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01991587"
    },
    {
      "nct_id": "NCT03328325",
      "title": "Age and Response to Flu Vaccines",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza",
        "Influenza Immunisation"
      ],
      "interventions": [
        {
          "name": "Influenza Virus Quadrivalent Inactivated Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "9 Years",
        "maximum_age": "99 Years",
        "sex": "ALL",
        "summary": "9 Years to 99 Years"
      },
      "enrollment_count": 152,
      "start_date": "2017-12-14",
      "completion_date": "2020-04-20",
      "has_results": true,
      "last_update_posted_date": "2026-08-28",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 2,
      "location_summary": "Rochester, New York",
      "locations": [
        {
          "city": "Rochester",
          "state": "New York"
        },
        {
          "city": "Rochester",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03328325"
    },
    {
      "nct_id": "NCT03673345",
      "title": "Development of Childhood Anti-Influenza Immunity",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza",
        "Influenza Immunisation"
      ],
      "interventions": [
        {
          "name": "Influenza Virus Quadrivalent Inactivated Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "3 Months",
        "maximum_age": "15 Years",
        "sex": "ALL",
        "summary": "3 Months to 15 Years"
      },
      "enrollment_count": 125,
      "start_date": "2018-09-25",
      "completion_date": "2020-12-22",
      "has_results": true,
      "last_update_posted_date": "2022-03-18",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 1,
      "location_summary": "Rochester, New York",
      "locations": [
        {
          "city": "Rochester",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03673345"
    },
    {
      "nct_id": "NCT05071313",
      "title": "A Study of an Ad26.RSV.preF-based Vaccine and High-dose Seasonal Influenza Vaccine, With and Without Coadministration, in Adults Aged 65 Years and Older",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Influenza, Human Prevention",
        "Respiratory Syncytial Viruses Prevention"
      ],
      "interventions": [
        {
          "name": "Ad26.RSV.preF-based vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent High-dose Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Janssen Vaccines & Prevention B.V.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 777,
      "start_date": "2021-10-04",
      "completion_date": "2022-10-11",
      "has_results": true,
      "last_update_posted_date": "2025-05-25",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 19,
      "location_summary": "Long Beach, California • Hollywood, Florida • Port Orange, Florida + 14 more",
      "locations": [
        {
          "city": "Long Beach",
          "state": "California"
        },
        {
          "city": "Hollywood",
          "state": "Florida"
        },
        {
          "city": "Port Orange",
          "state": "Florida"
        },
        {
          "city": "The Villages",
          "state": "Florida"
        },
        {
          "city": "Chicago",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05071313"
    },
    {
      "nct_id": "NCT05091307",
      "title": "A Study of Ad26.COV2.S and Influenza Vaccines in Healthy Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "COVID-19 Prevention"
      ],
      "interventions": [
        {
          "name": "Ad26.COV2.S",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        },
        {
          "name": "Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "Janssen Vaccines & Prevention B.V.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 861,
      "start_date": "2021-11-02",
      "completion_date": "2022-11-15",
      "has_results": true,
      "last_update_posted_date": "2025-05-25",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 17,
      "location_summary": "Tempe, Arizona • San Diego, California • Coral Gables, Florida + 12 more",
      "locations": [
        {
          "city": "Tempe",
          "state": "Arizona"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Coral Gables",
          "state": "Florida"
        },
        {
          "city": "Fort Myers",
          "state": "Florida"
        },
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05091307"
    },
    {
      "nct_id": "NCT05095844",
      "title": "National Vaccine Adverse Event Reporting Survey and Etiology",
      "overall_status": "UNKNOWN",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "COVID-19",
        "Vaccine Adverse Reaction",
        "Vaccine Reaction",
        "Vaccine or Biological Substance, Unspecified Causing Adverse Effects in Therapeutic Use",
        "Corona Virus Infection",
        "Blood Clot",
        "Thrombocytopenia",
        "Neuritis",
        "Vasculitis",
        "Influenza",
        "Guillain-Barré",
        "GWAS",
        "Genetic Sequencing"
      ],
      "interventions": [
        {
          "name": "vaccinated",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Neuroganics LLC",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "5 Years",
        "maximum_age": "99 Years",
        "sex": "ALL",
        "summary": "5 Years to 99 Years"
      },
      "enrollment_count": 100000,
      "start_date": "2022-03-15",
      "completion_date": "2024-04-01",
      "has_results": false,
      "last_update_posted_date": "2022-03-18",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 1,
      "location_summary": "Northglenn, Colorado",
      "locations": [
        {
          "city": "Northglenn",
          "state": "Colorado"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05095844"
    },
    {
      "nct_id": "NCT04896086",
      "title": "First-in-Human Clinical Trial of a Mosaic Quadrivalent Influenza Vaccine Compared With a Licensed Inactivated Seasonal QIV in Healthy Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Influenza",
        "Seasonal Influenza"
      ],
      "interventions": [
        {
          "name": "VRC-GENADJ0110-AP-NV (Adjuplex)",
          "type": "DRUG"
        },
        {
          "name": "Flucelvax",
          "type": "BIOLOGICAL"
        },
        {
          "name": "VRC-FLUMOS0111-00-VP (FluMos-v1)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG",
        "BIOLOGICAL"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "18 Years to 50 Years"
      },
      "enrollment_count": 63,
      "start_date": "2021-05-24",
      "completion_date": "2024-01-25",
      "has_results": true,
      "last_update_posted_date": "2025-04-27",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 1,
      "location_summary": "Bethesda, Maryland",
      "locations": [
        {
          "city": "Bethesda",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04896086"
    },
    {
      "nct_id": "NCT04077424",
      "title": "Senescent Immunity in Elders and Vaccine Responses (SILVER)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Flu Vaccine"
      ],
      "interventions": [
        {
          "name": "Fluzone-High Dose Quadrivalent",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluad",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Flublock",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Vanderbilt University Medical Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": "125 Years",
        "sex": "ALL",
        "summary": "65 Years to 125 Years"
      },
      "enrollment_count": 10,
      "start_date": "2019-10-21",
      "completion_date": "2020-02-01",
      "has_results": true,
      "last_update_posted_date": "2022-07-12",
      "last_synced_at": "2026-10-11T16:17:41.142Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04077424"
    }
  ]
}