{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+influenza+vaccine%2C+high-dose&page=2",
    "query": {
      "intervention": "Quadrivalent influenza vaccine, high-dose",
      "page": 2
    },
    "page_size": 10
  },
  "pagination": {
    "page": 2,
    "page_size": 10,
    "total_count": 56,
    "total_pages": 6,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+influenza+vaccine%2C+high-dose&page=3&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Quadrivalent+influenza+vaccine%2C+high-dose&page=1&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-11T17:04:21.017Z",
  "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": "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": "2026-10-11T17:04:21.017Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04077424"
    },
    {
      "nct_id": "NCT03722589",
      "title": "Immunogenicity Trial of Egg- Versus Non-Egg-Based Influenza Vaccines Among HCP",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Flublok",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Flucelvax",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluarix",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone High-Dose",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Centers for Disease Control and Prevention",
      "sponsor_class": "FED",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "18 Years to 65 Years"
      },
      "enrollment_count": 944,
      "start_date": "2018-09-12",
      "completion_date": "2020-07-31",
      "has_results": true,
      "last_update_posted_date": "2024-07-22",
      "last_synced_at": "2026-10-11T17:04:21.017Z",
      "location_count": 2,
      "location_summary": "Portland, Oregon • Temple, Texas",
      "locations": [
        {
          "city": "Portland",
          "state": "Oregon"
        },
        {
          "city": "Temple",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03722589"
    },
    {
      "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": "2026-10-11T17:04:21.017Z",
      "location_count": 1,
      "location_summary": "Minneapolis, Minnesota",
      "locations": [
        {
          "city": "Minneapolis",
          "state": "Minnesota"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05663463"
    },
    {
      "nct_id": "NCT06060457",
      "title": "A Study to Evaluate the Safety and Immune Response of mRNA-1345, a Vaccine Targeting Respiratory Syncytial Virus (RSV), When Co-administered With a Fluzone HD, in Adults ≥65 Years of Age",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Respiratory Syncytial Virus"
      ],
      "interventions": [
        {
          "name": "Placebo",
          "type": "BIOLOGICAL"
        },
        {
          "name": "mRNA-1345",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone HD",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "ModernaTX, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 1900,
      "start_date": "2023-09-25",
      "completion_date": "2024-06-07",
      "has_results": true,
      "last_update_posted_date": "2025-07-30",
      "last_synced_at": "2026-10-11T17:04:21.017Z",
      "location_count": 34,
      "location_summary": "Scottsdale, Arizona • Dublin, California • Riverside, California + 29 more",
      "locations": [
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Dublin",
          "state": "California"
        },
        {
          "city": "Riverside",
          "state": "California"
        },
        {
          "city": "Rolling Hills Estates",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06060457"
    },
    {
      "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": "2026-10-11T17:04:21.017Z",
      "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": "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": "2026-10-11T17:04:21.017Z",
      "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": "NCT06744205",
      "title": "A Study on the Safety and Immunogenicity of Hexavalent Influenza mRNA Vaccine in Adult Participants 50 Years of Age and Older",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Influenza",
        "Healthy Volunteers"
      ],
      "interventions": [
        {
          "name": "Trivalent (TIV) messenger ribonucleic acid (mRNA) hemagglutinin (HA) Vaccine 1",
          "type": "BIOLOGICAL"
        },
        {
          "name": "TIV mRNA-neuraminidase (NA)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "TIV mRNA-HA Vaccine 2",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza Standard Dose Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza Vaccine High Dose",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Sanofi Pasteur, a Sanofi Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 1162,
      "start_date": "2025-01-06",
      "completion_date": "2026-05-22",
      "has_results": false,
      "last_update_posted_date": "2026-06-09",
      "last_synced_at": "2026-10-11T17:04:21.017Z",
      "location_count": 21,
      "location_summary": "Birmingham, Alabama • Mobile, Alabama • Tempe, Arizona + 18 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Mobile",
          "state": "Alabama"
        },
        {
          "city": "Tempe",
          "state": "Arizona"
        },
        {
          "city": "Coral Gables",
          "state": "Florida"
        },
        {
          "city": "DeLand",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06744205"
    },
    {
      "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": "2026-10-11T17:04:21.017Z",
      "location_count": 1,
      "location_summary": "Stanford, California",
      "locations": [
        {
          "city": "Stanford",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01827462"
    },
    {
      "nct_id": "NCT05945485",
      "title": "A Study to Evaluate the Safety and Immunogenicity of Two Doses of DCVC H1 HA mRNA-LNP in Healthy Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Influenza"
      ],
      "interventions": [
        {
          "name": "DCVC H1 HA mRNA vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Recombinant Seasonal Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Sodium Chloride, 0.9%",
          "type": "OTHER"
        }
      ],
      "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": "2023-10-16",
      "completion_date": "2026-05-21",
      "has_results": false,
      "last_update_posted_date": "2026-06-22",
      "last_synced_at": "2026-10-11T17:04:21.017Z",
      "location_count": 1,
      "location_summary": "Iowa City, Iowa",
      "locations": [
        {
          "city": "Iowa City",
          "state": "Iowa"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05945485"
    },
    {
      "nct_id": "NCT03308825",
      "title": "Safety and Immunogenicity of Fluzone® Quadrivalent and Fluzone® High-Dose, Influenza Vaccines",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Influenza",
        "Flu"
      ],
      "interventions": [
        {
          "name": "Fluzone Quadrivalent vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone High-Dose vaccine",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Sanofi Pasteur, a Sanofi Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "6 Months",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "6 Months and older"
      },
      "enrollment_count": 240,
      "start_date": "2017-09-11",
      "completion_date": "2017-11-22",
      "has_results": true,
      "last_update_posted_date": "2022-03-29",
      "last_synced_at": "2026-10-11T17:04:21.017Z",
      "location_count": 3,
      "location_summary": "Council Bluffs, Iowa • Bardstown, Kentucky • Metairie, Louisiana",
      "locations": [
        {
          "city": "Council Bluffs",
          "state": "Iowa"
        },
        {
          "city": "Bardstown",
          "state": "Kentucky"
        },
        {
          "city": "Metairie",
          "state": "Louisiana"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03308825"
    }
  ]
}