{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+Inactivated+Influenza+High+Dose+QIV-HD",
    "query": {
      "intervention": "Quadrivalent Inactivated Influenza High Dose QIV-HD"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 10,
    "total_pages": 1,
    "next_page_url": null,
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-29T12:35:41.581Z",
  "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": "2026-09-29T12:35:41.581Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04613206"
    },
    {
      "nct_id": "NCT05007041",
      "title": "Simultaneous RZV and aIIV4 Vaccination",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Pain",
        "Quality of Life",
        "Injection Site Reaction",
        "Adverse Drug Event"
      ],
      "interventions": [
        {
          "name": "FLUAD® Quadrivalent",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone® High-Dose Quadrivalent",
          "type": "BIOLOGICAL"
        },
        {
          "name": "SHINGRIX®",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Duke University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 267,
      "start_date": "2021-09-21",
      "completion_date": "2023-06-08",
      "has_results": true,
      "last_update_posted_date": "2024-07-11",
      "last_synced_at": "2026-09-29T12:35:41.581Z",
      "location_count": 2,
      "location_summary": "Baltimore, Maryland • Durham, North Carolina",
      "locations": [
        {
          "city": "Baltimore",
          "state": "Maryland"
        },
        {
          "city": "Durham",
          "state": "North Carolina"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05007041"
    },
    {
      "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": "2026-09-29T12:35:41.581Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05215327"
    },
    {
      "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": "2026-09-29T12:35:41.581Z",
      "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": "NCT04969276",
      "title": "Study of a Quadrivalent High-Dose Influenza Vaccine and a Moderna COVID-19 Vaccine Administered Either Concomitantly or Singly in Participants 65 Years of Age and Older Previously Vaccinated With a 2-dose Schedule of Moderna COVID-19 Vaccine",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Influenza Immunization",
        "Healthy Volunteers"
      ],
      "interventions": [
        {
          "name": "Quadrivalent Inactivated Influenza High Dose",
          "type": "BIOLOGICAL"
        },
        {
          "name": "COVID-19 mRNA Vaccine (nucleoside modified)",
          "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": 306,
      "start_date": "2021-07-16",
      "completion_date": "2022-02-08",
      "has_results": true,
      "last_update_posted_date": "2025-09-12",
      "last_synced_at": "2026-09-29T12:35:41.581Z",
      "location_count": 6,
      "location_summary": "Glendale, Arizona • San Diego, California • Vista, California + 3 more",
      "locations": [
        {
          "city": "Glendale",
          "state": "Arizona"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Vista",
          "state": "California"
        },
        {
          "city": "Centennial",
          "state": "Colorado"
        },
        {
          "city": "Peoria",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04969276"
    },
    {
      "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": "2026-09-29T12:35:41.581Z",
      "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": "NCT06029933",
      "title": "Fluad vs. Fluzone High-Dose Vaccine Effectiveness Among Adults ≥65 Years",
      "overall_status": "RECRUITING",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Influenza",
        "Community-acquired Pneumonia",
        "Cardiovascular Events"
      ],
      "interventions": [
        {
          "name": "Adjuvanted Quadrivalent Inactivated Influenza Vaccine (aIIV4)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "High-Dose Quadrivalent Inactivated Influenza Vaccine (HD-IIV4)",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Kaiser Permanente",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 1500000,
      "start_date": "2023-08-17",
      "completion_date": "2028-05",
      "has_results": false,
      "last_update_posted_date": "2026-08-05",
      "last_synced_at": "2026-09-29T12:35:41.581Z",
      "location_count": 1,
      "location_summary": "Oakland, California",
      "locations": [
        {
          "city": "Oakland",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06029933"
    },
    {
      "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": "2026-09-29T12:35:41.581Z",
      "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": "2026-09-29T12:35:41.581Z",
      "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": "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": "2026-09-29T12:35:41.581Z",
      "location_count": 1,
      "location_summary": "St Louis, Missouri",
      "locations": [
        {
          "city": "St Louis",
          "state": "Missouri"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02500680"
    }
  ]
}