{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+Influenza+Standard+Dose+Vaccine&page=2",
    "query": {
      "intervention": "Quadrivalent Influenza Standard Dose Vaccine",
      "page": 2
    },
    "page_size": 10
  },
  "pagination": {
    "page": 2,
    "page_size": 10,
    "total_count": 31,
    "total_pages": 4,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+Influenza+Standard+Dose+Vaccine&page=3&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+Influenza+Standard+Dose+Vaccine&page=1&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-08T22:21:32.815Z",
  "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": "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": "2026-10-08T22:21:32.815Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03743688"
    },
    {
      "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": "2026-10-08T22:21:32.815Z",
      "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": "NCT03179761",
      "title": "High vs. Standard Dose Flu Vaccine in Adult Stem Cell Transplant Recipients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Hematopoietic Cell Transplantation"
      ],
      "interventions": [
        {
          "name": "Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Laboratory Biomarker Analysis",
          "type": "OTHER"
        },
        {
          "name": "Trivalent Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "Vanderbilt-Ingram 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": 124,
      "start_date": "2017-10-09",
      "completion_date": "2024-10-01",
      "has_results": true,
      "last_update_posted_date": "2024-12-04",
      "last_synced_at": "2026-10-08T22:21:32.815Z",
      "location_count": 4,
      "location_summary": "Birmingham, Alabama • Chicago, Illinois • Nashville, Tennessee + 1 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Chicago",
          "state": "Illinois"
        },
        {
          "city": "Nashville",
          "state": "Tennessee"
        },
        {
          "city": "Seattle",
          "state": "Washington"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03179761"
    },
    {
      "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": "2026-10-08T22:21:32.815Z",
      "location_count": 1,
      "location_summary": "Bethesda, Maryland",
      "locations": [
        {
          "city": "Bethesda",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03845231"
    },
    {
      "nct_id": "NCT04487041",
      "title": "Tfh Dysfunction in HIV and Aging",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Human Influenza"
      ],
      "interventions": [
        {
          "name": "Standard dose influenza vaccination",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High dose influenza vaccination",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "University of Miami",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 400,
      "start_date": "2020-10-30",
      "completion_date": "2027-12-30",
      "has_results": false,
      "last_update_posted_date": "2026-07-17",
      "last_synced_at": "2026-10-08T22:21:32.815Z",
      "location_count": 1,
      "location_summary": "Miami, Florida",
      "locations": [
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04487041"
    },
    {
      "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": "2026-10-08T22:21:32.815Z",
      "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": "NCT05947071",
      "title": "High vs.Standard Dose Influenza Vaccine in Pediatric Solid Organ Transplant (SOT) Recipients",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Immunization; Infection",
        "Transplantation Infection",
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Standard Dose Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High Dose Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "3 Years",
        "maximum_age": "17 Years",
        "sex": "ALL",
        "summary": "3 Years to 17 Years"
      },
      "enrollment_count": 312,
      "start_date": "2024-09-26",
      "completion_date": "2027-09-01",
      "has_results": false,
      "last_update_posted_date": "2026-09-24",
      "last_synced_at": "2026-10-08T22:21:32.815Z",
      "location_count": 10,
      "location_summary": "Stanford, California • Atlanta, Georgia • Chicago, Illinois + 7 more",
      "locations": [
        {
          "city": "Stanford",
          "state": "California"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Chicago",
          "state": "Illinois"
        },
        {
          "city": "Kansas City",
          "state": "Missouri"
        },
        {
          "city": "Cincinnati",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05947071"
    },
    {
      "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": "2026-10-08T22:21:32.815Z",
      "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": "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": "2026-10-08T22:21:32.815Z",
      "location_count": 1,
      "location_summary": "Marshfield, Wisconsin",
      "locations": [
        {
          "city": "Marshfield",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03598439"
    },
    {
      "nct_id": "NCT05028361",
      "title": "Simultaneous mRNA COVID-19 and IIV4 Vaccination Study",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Quality of Life",
        "Injection Site Reaction",
        "Adverse Drug Event",
        "Systemic Reaction"
      ],
      "interventions": [
        {
          "name": "mRNA COVID-19",
          "type": "BIOLOGICAL"
        },
        {
          "name": "IIV4",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo (saline)",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "Duke University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "5 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "5 Years and older"
      },
      "enrollment_count": 348,
      "start_date": "2021-10-04",
      "completion_date": "2023-06-15",
      "has_results": true,
      "last_update_posted_date": "2024-03-19",
      "last_synced_at": "2026-10-08T22:21:32.815Z",
      "location_count": 3,
      "location_summary": "Baltimore, Maryland • Durham, North Carolina • Cincinnati, Ohio",
      "locations": [
        {
          "city": "Baltimore",
          "state": "Maryland"
        },
        {
          "city": "Durham",
          "state": "North Carolina"
        },
        {
          "city": "Cincinnati",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05028361"
    }
  ]
}