{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+Inactivated+Influenza+High+Dose",
    "query": {
      "intervention": "Quadrivalent Inactivated Influenza High Dose"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 19,
    "total_pages": 2,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+Inactivated+Influenza+High+Dose&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-25T14:19:12.541Z",
  "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": "NCT04613206",
      "title": "High vs. Standard Dose Influenza Vaccine in Adult SOT Recipients",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Immunization; Infection",
        "Transplantation Infection",
        "Influenza",
        "Solid Organ Transplant"
      ],
      "interventions": [
        {
          "name": "High Dose Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Standard Dose Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Vanderbilt 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": 396,
      "start_date": "2021-01-11",
      "completion_date": "2026-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-01-21",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04613206"
    },
    {
      "nct_id": "NCT05755620",
      "title": "A Study to Evaluate the Safety and Immunogenicity of a Single Dose of H1ssF-3928 mRNA-LNP in Healthy Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Influenza Virus Quadrivalent Inactivated Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Sodium Chloride, 0.9%",
          "type": "OTHER"
        },
        {
          "name": "VRC-FLUNPF099-00-VP (H1ssF_3928)",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "OTHER"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "49 Years",
        "sex": "ALL",
        "summary": "18 Years to 49 Years"
      },
      "enrollment_count": 50,
      "start_date": "2023-04-05",
      "completion_date": "2025-10-03",
      "has_results": false,
      "last_update_posted_date": "2026-06-18",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 1,
      "location_summary": "Durham, North Carolina",
      "locations": [
        {
          "city": "Durham",
          "state": "North Carolina"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05755620"
    },
    {
      "nct_id": "NCT03698279",
      "title": "Safety and Immunogenicity of Different Dosages of High-Dose Quadrivalent Influenza Vaccine in Children 6 Months to 17 Years of Age",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "High-Dose Quadrivalent Influenza Vaccine (QIV-HD) 30 μg (split-virion, inactivated)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High-Dose Quadrivalent Influenza Vaccine (QIV-HD) 45 μg, (split-virion, inactivated)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High-Dose Quadrivalent Influenza Vaccine (QIV-HD) 60 µg (split-virion, inactivated)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluarix Quadrivalent Influenza vaccine (Unadjuvanted QIV-SD) (Inactivated)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "FLUAD Pediatric (adjuvanted TIV) (Surface Antigen, Inactivated)",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Sanofi Pasteur, a Sanofi Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "6 Months",
        "maximum_age": "17 Years",
        "sex": "ALL",
        "summary": "6 Months to 17 Years"
      },
      "enrollment_count": 665,
      "start_date": "2018-10-09",
      "completion_date": "2019-10-16",
      "has_results": true,
      "last_update_posted_date": "2022-04-04",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 13,
      "location_summary": "San Diego, California • Miami, Florida • Atlanta, Georgia + 8 more",
      "locations": [
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Miami",
          "state": "Florida"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "El Dorado",
          "state": "Kansas"
        },
        {
          "city": "Newton",
          "state": "Kansas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03698279"
    },
    {
      "nct_id": "NCT05663463",
      "title": "Seasonal Influenza Vaccine High Dose Boosting in Solid Organ Transplant Recipients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Solid Organ Transplant"
      ],
      "interventions": [
        {
          "name": "Fluzone High-Dose - 2 doses",
          "type": "DRUG"
        },
        {
          "name": "Fluzone High-Dose - 1 dose of HD",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of Minnesota",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 74,
      "start_date": "2023-09-11",
      "completion_date": "2025-06-16",
      "has_results": false,
      "last_update_posted_date": "2025-07-15",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 1,
      "location_summary": "Minneapolis, Minnesota",
      "locations": [
        {
          "city": "Minneapolis",
          "state": "Minnesota"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05663463"
    },
    {
      "nct_id": "NCT02553343",
      "title": "A Study of the Safety and Immunogenicity of High-Dose Quadrivalent Influenza Vaccine in Subjects Aged 65 Years and Older",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "High-dose quadrivalent influenza virus vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High-dose influenza virus vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High-dose trivalent inactivated influenza vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Sanofi Pasteur, a Sanofi Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 792,
      "start_date": "2015-09",
      "completion_date": "2016-04-04",
      "has_results": false,
      "last_update_posted_date": "2018-02-09",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 9,
      "location_summary": "Milford, Connecticut • Coral Gables, Florida • Wichita, Kansas + 6 more",
      "locations": [
        {
          "city": "Milford",
          "state": "Connecticut"
        },
        {
          "city": "Coral Gables",
          "state": "Florida"
        },
        {
          "city": "Wichita",
          "state": "Kansas"
        },
        {
          "city": "St Louis",
          "state": "Missouri"
        },
        {
          "city": "Rochester",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02553343"
    },
    {
      "nct_id": "NCT05624606",
      "title": "Safety and Immunogenicity of Quadrivalent Influenza mRNA Vaccine MRT5410 in Adult Participants 18 Years of Age and Older",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Influenza Immunization"
      ],
      "interventions": [
        {
          "name": "Quadrivalent Influenza mRNA Vaccine MRT5410",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Recombinant Influenza vaccine RIV4",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Inactivated Influenza Standard Dose QIV-SD",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Inactivated Influenza High Dose QIV-HD",
          "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": 682,
      "start_date": "2022-11-28",
      "completion_date": "2024-03-28",
      "has_results": false,
      "last_update_posted_date": "2025-03-18",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 23,
      "location_summary": "Huntington Park, California • Long Beach, California • North Hollywood, California + 19 more",
      "locations": [
        {
          "city": "Huntington Park",
          "state": "California"
        },
        {
          "city": "Long Beach",
          "state": "California"
        },
        {
          "city": "North Hollywood",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Gainesville",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05624606"
    },
    {
      "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": "2026-09-25T14:19:12.541Z",
      "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": "NCT01827462",
      "title": "Comparison of Immune Responses to Influenza Vaccine In Adults of Different Ages (SLVP015 2007-2017)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Trivalent, inactivated influenza vaccine (TIV)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent, inactivated influenza vaccine (IIV4)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High-Dose Trivalent, inactivated influenza vaccine (TIV High-Dose)",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Stanford University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "100 Years",
        "sex": "ALL",
        "summary": "18 Years to 100 Years"
      },
      "enrollment_count": 136,
      "start_date": "2007-10",
      "completion_date": "2017-03",
      "has_results": true,
      "last_update_posted_date": "2017-07-11",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 1,
      "location_summary": "Stanford, California",
      "locations": [
        {
          "city": "Stanford",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01827462"
    },
    {
      "nct_id": "NCT05215327",
      "title": "High vs. Standard Dose Influenza Vaccine in Lung Allograft Recipients",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Immunization; Infection",
        "Transplantation Infection",
        "Influenza"
      ],
      "interventions": [
        {
          "name": "High Dose Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Standard Dose Quadrivalent Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Vanderbilt University Medical Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "16 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "16 Years and older"
      },
      "enrollment_count": 270,
      "start_date": "2022-11-08",
      "completion_date": "2027-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-09-04",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05215327"
    },
    {
      "nct_id": "NCT03312699",
      "title": "Effects of Aging on Primary and Secondary Vaccine Responses",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Influenza",
        "Hepatitis A",
        "Typhoid",
        "Healthy Adults"
      ],
      "interventions": [
        {
          "name": "Fluzone® quadrivalent",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone High Dose",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluad",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Vaqta",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Typhim Vi",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Vivotif",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Stanford University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 54,
      "start_date": "2017-09-19",
      "completion_date": "2023-12-31",
      "has_results": false,
      "last_update_posted_date": "2024-12-16",
      "last_synced_at": "2026-09-25T14:19:12.541Z",
      "location_count": 1,
      "location_summary": "Stanford, California",
      "locations": [
        {
          "city": "Stanford",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03312699"
    }
  ]
}