{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Fluzone%C2%AE+High-Dose+%28HD%29+influenza+vaccine",
    "query": {
      "intervention": "Fluzone® High-Dose (HD) influenza vaccine"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 15,
    "total_pages": 2,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Fluzone%C2%AE+High-Dose+%28HD%29+influenza+vaccine&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-09T23:13:40.442Z",
  "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": "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": "2026-10-09T23:13:40.442Z",
      "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": "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": "2027-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-10-02",
      "last_synced_at": "2026-10-09T23:13:40.442Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04613206"
    },
    {
      "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": "2026-10-09T23:13:40.442Z",
      "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": "NCT07300085",
      "title": "A Trial to Evaluate the Effect of CD388/MK1406 on the Immunogenicity of Fluzone® HD Vaccine (CD388.SQ.1.08/MK-1406-007)",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Healthy Participants"
      ],
      "interventions": [
        {
          "name": "Fluzone® High-Dose (HD) influenza vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "MK-1406 Injection",
          "type": "COMBINATION_PRODUCT"
        },
        {
          "name": "Placebo",
          "type": "COMBINATION_PRODUCT"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "COMBINATION_PRODUCT"
      ],
      "sponsor": "Cidara Therapeutics Inc., a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA)",
      "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": 710,
      "start_date": "2025-11-08",
      "completion_date": "2026-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-08-19",
      "last_synced_at": "2026-10-09T23:13:40.442Z",
      "location_count": 4,
      "location_summary": "Glendale, California • Baltimore, Maryland",
      "locations": [
        {
          "city": "Glendale",
          "state": "California"
        },
        {
          "city": "Glendale",
          "state": "California"
        },
        {
          "city": "Baltimore",
          "state": "Maryland"
        },
        {
          "city": "Baltimore",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07300085"
    },
    {
      "nct_id": "NCT07192458",
      "title": "High vs. Standard Dose Influenza Vaccines in Lung Transplant (Repeater)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Immunization; Infection|Transplantation Infection|Influenza",
        "Influenza"
      ],
      "interventions": [
        {
          "name": "Fluzone High Dose Inactivated Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone Standard Dose 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": 60,
      "start_date": "2025-09-17",
      "completion_date": "2029-12",
      "has_results": false,
      "last_update_posted_date": "2025-10-07",
      "last_synced_at": "2026-10-09T23:13:40.442Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07192458"
    },
    {
      "nct_id": "NCT03183908",
      "title": "FLUAD® vs. Fluzone® High-Dose Study",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Pain",
        "Quality of Life",
        "Injection Site Reaction",
        "Side Effect of Drug",
        "Adverse Drug Event"
      ],
      "interventions": [
        {
          "name": "FLUAD®",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Fluzone® High-Dose",
          "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": 757,
      "start_date": "2017-08-28",
      "completion_date": "2019-02-14",
      "has_results": true,
      "last_update_posted_date": "2021-03-30",
      "last_synced_at": "2026-10-09T23:13:40.442Z",
      "location_count": 4,
      "location_summary": "Atlanta, Georgia • Boston, Massachusetts • Durham, North Carolina + 1 more",
      "locations": [
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Boston",
          "state": "Massachusetts"
        },
        {
          "city": "Durham",
          "state": "North Carolina"
        },
        {
          "city": "Cincinnati",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03183908"
    },
    {
      "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": "2026-10-09T23:13:40.442Z",
      "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": "NCT05553301",
      "title": "Safety and Immunogenicity of Quadrivalent Influenza mRNA Vaccine MRT5407 in Adult Participants18 Years of Age and Older",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Influenza Immunization"
      ],
      "interventions": [
        {
          "name": "Quadrivalent Influenza mRNA Vaccine MRT5407",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Recombinant Influenza Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza Standard Dose Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Quadrivalent Influenza High-Dose Vaccine",
          "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": 560,
      "start_date": "2022-10-03",
      "completion_date": "2024-01-19",
      "has_results": false,
      "last_update_posted_date": "2025-01-24",
      "last_synced_at": "2026-10-09T23:13:40.442Z",
      "location_count": 23,
      "location_summary": "Rolling Hills Estates, California • San Diego, California • DeLand, Florida + 16 more",
      "locations": [
        {
          "city": "Rolling Hills Estates",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "DeLand",
          "state": "Florida"
        },
        {
          "city": "Gainesville",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05553301"
    },
    {
      "nct_id": "NCT05518500",
      "title": "A Deep Longitudinal Analysis of Next Generation Influenza Vaccines in Older Adults",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Aging",
        "Influenza Vaccine",
        "Dendritic Cell",
        "Vaccine Response"
      ],
      "interventions": [
        {
          "name": "Flu Vaccine (Year 1)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Flu Vaccine (Year 2)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Flu Vaccine (Year 3)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Flu Vaccine (Year 4)",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "The Jackson Laboratory",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "65 Years and older"
      },
      "enrollment_count": 75,
      "start_date": "2022-08-31",
      "completion_date": "2026-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-08-03",
      "last_synced_at": "2026-10-09T23:13:40.442Z",
      "location_count": 1,
      "location_summary": "Farmington, Connecticut",
      "locations": [
        {
          "city": "Farmington",
          "state": "Connecticut"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05518500"
    },
    {
      "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": "2026-10-09T23:13:40.442Z",
      "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"
    }
  ]
}