{ "api_version": "1", "request": { "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=HD+quadrivalent+influenza+vaccine", "query": { "intervention": "HD quadrivalent influenza vaccine" }, "page_size": 10 }, "pagination": { "page": 1, "page_size": 10, "total_count": 30, "total_pages": 3, "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=HD+quadrivalent+influenza+vaccine&page=2&page_size=10", "previous_page_url": null }, "source": "remote", "last_synced_at": "2026-10-04T10:54:16.278Z", "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": "NCT06361875", "title": "A Study to Investigate the Safety and Immunogenicity of the Quadrivalent Influenza mRNA Vaccines in Adults Aged 18 Years and Above", "overall_status": "COMPLETED", "study_type": "INTERVENTIONAL", "phases": [ "PHASE1", "PHASE2" ], "conditions": [ "Influenza Immunization", "Healthy Volunteers" ], "interventions": [ { "name": "Quadrivalent Influenza mRNA Vaccine MRT5421", "type": "BIOLOGICAL" }, { "name": "Quadrivalent Influenza mRNA Vaccine MRT5424", "type": "BIOLOGICAL" }, { "name": "Quadrivalent Influenza mRNA Vaccine MRT5429", "type": "BIOLOGICAL" }, { "name": "Quadrivalent Influenza Standard Dose Vaccine", "type": "BIOLOGICAL" }, { "name": "Quadrivalent Influenza High-Dose Vaccine", "type": "BIOLOGICAL" }, { "name": "Quadrivalent Recombinant Influenza 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": 908, "start_date": "2024-04-01", "completion_date": "2025-06-09", "has_results": true, "last_update_posted_date": "2026-08-04", "last_synced_at": "2026-10-04T10:54:16.278Z", "location_count": 11, "location_summary": "San Diego, California • Hialeah, Florida • Hollywood, Florida + 8 more", "locations": [ { "city": "San Diego", "state": "California" }, { "city": "Hialeah", "state": "Florida" }, { "city": "Hollywood", "state": "Florida" }, { "city": "Indianapolis", "state": "Indiana" }, { "city": "Lexington", "state": "Kentucky" } ], "official_url": "https://clinicaltrials.gov/study/NCT06361875" }, { "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": "2026-10-04T10:54:16.278Z", "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": "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": "2026-10-04T10:54:16.278Z", "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": "NCT05827978", "title": "Study of mRNA-1010 Seasonal Influenza Vaccine in Adults", "overall_status": "COMPLETED", "study_type": "INTERVENTIONAL", "phases": [ "PHASE3" ], "conditions": [ "Seasonal Influenza" ], "interventions": [ { "name": "mRNA-1010", "type": "BIOLOGICAL" }, { "name": "Licensed Quadrivalent Inactivated Seasonal Influenza Vaccine", "type": "BIOLOGICAL" } ], "intervention_types": [ "BIOLOGICAL" ], "sponsor": "ModernaTX, Inc.", "sponsor_class": "INDUSTRY", "healthy_volunteers": true, "eligibility": { "minimum_age": "18 Years", "maximum_age": null, "sex": "ALL", "summary": "18 Years and older" }, "enrollment_count": 8411, "start_date": "2023-04-17", "completion_date": "2024-06-24", "has_results": true, "last_update_posted_date": "2025-07-10", "last_synced_at": "2026-10-04T10:54:16.278Z", "location_count": 103, "location_summary": "Anniston, Alabama • Athens, Alabama • Cullman, Alabama + 85 more", "locations": [ { "city": "Anniston", "state": "Alabama" }, { "city": "Athens", "state": "Alabama" }, { "city": "Cullman", "state": "Alabama" }, { "city": "Huntsville", "state": "Alabama" }, { "city": "Mesa", "state": "Arizona" } ], "official_url": "https://clinicaltrials.gov/study/NCT05827978" }, { "nct_id": "NCT03658629", "title": "Phase 2 Dose and Formulation Confirmation of Quad-NIV in Older Adults", "overall_status": "TERMINATED", "study_type": "INTERVENTIONAL", "phases": [ "PHASE2" ], "conditions": [ "Influenza, Human" ], "interventions": [ { "name": "NanoFlu (Quad-NIV)", "type": "BIOLOGICAL" }, { "name": "Matrix-M Adjuvant", "type": "OTHER" }, { "name": "Placebo", "type": "OTHER" }, { "name": "Fluzone HD", "type": "BIOLOGICAL" }, { "name": "Flublok Quadrivalent", "type": "BIOLOGICAL" }, { "name": "Influenza Vaccine", "type": "BIOLOGICAL" } ], "intervention_types": [ "BIOLOGICAL", "OTHER" ], "sponsor": "Novavax", "sponsor_class": "INDUSTRY", "healthy_volunteers": true, "eligibility": { "minimum_age": "65 Years", "maximum_age": null, "sex": "ALL", "summary": "65 Years and older" }, "enrollment_count": 1375, "start_date": "2018-09-24", "completion_date": "2019-04-26", "has_results": true, "last_update_posted_date": "2022-11-04", "last_synced_at": "2026-10-04T10:54:16.278Z", "location_count": 14, "location_summary": "Hollywood, Florida • Savannah, Georgia • Stockbridge, Georgia + 11 more", "locations": [ { "city": "Hollywood", "state": "Florida" }, { "city": "Savannah", "state": "Georgia" }, { "city": "Stockbridge", "state": "Georgia" }, { "city": "Rockville", "state": "Maryland" }, { "city": "Norfolk", "state": "Nebraska" } ], "official_url": "https://clinicaltrials.gov/study/NCT03658629" }, { "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": "2026-10-04T10:54:16.278Z", "location_count": 1, "location_summary": "Oakland, California", "locations": [ { "city": "Oakland", "state": "California" } ], "official_url": "https://clinicaltrials.gov/study/NCT06029933" }, { "nct_id": "NCT05426174", "title": "Study to Assess the Safety and Immunogenicity of Monovalent mRNA NA Vaccine in Adult Participants 18 Years of Age and Older", "overall_status": "COMPLETED", "study_type": "INTERVENTIONAL", "phases": [ "PHASE1" ], "conditions": [ "Influenza Immunization", "Healthy Volunteers" ], "interventions": [ { "name": "mRNA NA vaccine", "type": "BIOLOGICAL" }, { "name": "High Dose Quadrivalent Influenza 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": 233, "start_date": "2022-06-09", "completion_date": "2024-01-03", "has_results": false, "last_update_posted_date": "2025-09-15", "last_synced_at": "2026-10-04T10:54:16.278Z", "location_count": 6, "location_summary": "Huntsville, Alabama • Phoenix, Arizona • San Diego, California + 3 more", "locations": [ { "city": "Huntsville", "state": "Alabama" }, { "city": "Phoenix", "state": "Arizona" }, { "city": "San Diego", "state": "California" }, { "city": "Melbourne", "state": "Florida" }, { "city": "Peoria", "state": "Illinois" } ], "official_url": "https://clinicaltrials.gov/study/NCT05426174" }, { "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": "2026-10-04T10:54:16.278Z", "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": "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": "2026-10-04T10:54:16.278Z", "location_count": 1, "location_summary": "St Louis, Missouri", "locations": [ { "city": "St Louis", "state": "Missouri" } ], "official_url": "https://clinicaltrials.gov/study/NCT02500680" }, { "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": "2026-10-04T10:54:16.278Z", "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" } ] }