Effect of High-Dose Quadrivalent Influenza Vaccine (Efluelda®) Versus Standard-Dose (QIV-SD), in Subjects 65 Years of Age and Older on Innate Immunity, Including Gene Expression

Study Overview
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Brief Summary
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The purpose of the study is to evaluate innate and adaptive immunity following QIV-HD vaccination compared to QIV-SD vaccination in people 65 years of age and older.

Detailed Description
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The hypothesis is that higher dose of antigen can increase the intensity and the quality of innate immunity, as the adaptive humoral and cellular responses. In this study, the objectif is to evaluate innate and adaptive immunity following QIV-HD vaccination compared to QIV-SD vaccination in people 65 years of age and older. Modifications of early blood molecular (transcriptome) and cellular (blood phenotyping) signatures within the first 24 hours following vaccination will be investigated. The association between early gene signature and late influenza-specific humoral immune responses weeks/months after vaccination will be also assessed. This study is a hase IV, randomized, open-label, active-controlled, multi-center study comparing the immune response induced by QIV-HD vaccine (intervention) and QIV-SD vaccine (control).

Official Title
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Effect of High-Dose Quadrivalent Influenza Vaccine (Efluelda®) Versus Standard-Dose (QIV-SD), in Subjects 65 Years of Age and Older on Innate Immunity, Including Gene Expression

Conditions
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Vaccine Reaction

Intervention / Treatment
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* Biological: Experimental arm : High-Dose Quadrivalent Influenza Vaccine (Efluelda)
* Biological: Active Comparator: Standard-Dose Quadrivalent Influenza Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 65 years or older, the day of inclusion; Have signed and dated Informed Consent Form; Able and willing to attend all scheduled visits, and to comply with study procedures; Covered by French health insurance. Non-Inclusion Criteria : Any vaccine injection (including COVID-19 vaccine) in the 4 weeks preceding study inclusion; Plan to receive any vaccine (including COVID-19 vaccine) in the 4 weeks following study inclusion; Already vaccinated against influenza for 2021-2022 season; Hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccines used in the study or to a vaccine containing any of the same substances; HIV infection; Active Hepatitis B, or active Hepatitis C; Previous Guillain Barré syndrome; Ongoing immunosuppressive treatment or active immunodeficiency; Receipt of immune globulins, blood or blood-derived products in the past 3 months; Thrombocytopenia or bleeding disorder, receipt of anticoagulants contraindicating IM vaccination based on investigator's judgment; Influenza-like illness symptoms, including COVID-19, within 4 weeks before study inclusion; Personnes referred to in articles L1121-6 and L1121-8 of Public Health Code (persons deprived of liberty by judicial or administrative decision and persons subject to a legal protection measure: guardianship or curatorship). Exclusion Criteria: Any subject presenting with influenza-like illness symptoms, including COVID-19 between inclusion (visit 1) and randomization (visit 2); Subject unable to attempt visit at Day 0 (visit 2) and Day 1 (visit 3); Blood sample at Day 0 (visit 2) impossible to obtain; Receipt of vaccine injection or equivalent between inclusion (visit 1) and randomization (visit 2), other than those allowed and planned in the study. This includes non-study dose of 2021-2022 influenza vaccine, blood-derived immune globulins, blood, or blood-derived products. Any unexpected event relevant to the physician in charge, after discussion with the coordinating investigator and the sponsor

Ages Eligible for Study
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Minimum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High-Dose Quadrivalent Influenza Vaccine<br>One injection of the high-dose Efluelda vaccine will be given to the patient | Biological: Experimental arm : High-Dose Quadrivalent Influenza Vaccine (Efluelda)<br>* Patient will received one dose of High Dose Quadrivalent Influenza Vaccine according to marketing authorization.<br>|
| Active Comparator: Standard-Dose Quadrivalent Influenza Vaccine<br>One injection of the standard-dose Influvactetra vaccine will be given to the patient | Biological: Active Comparator: Standard-Dose Quadrivalent Influenza Vaccine<br>* Patient will received one dose of Standard Dose Quadrivalent Influenza Vaccine according to marketing authorization.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of Transcriptomic profiles | Transcriptomic profiles of blood cells (microarrays) will be performed to measure early systemic innate immune response | Change from Baseline Transcriptomic profiles at day after vaccine injection (Day 1) | 
| Change of Innate cellular phenotyping | Innate cellular phenotyping will be performed using 36 surface markers deciphering lineage cells monocytes, neutrophils, NK, antigen-presenting cells. | Change from Baseline Innate cellular phenotyping at day after vaccine injection (Day 1) | 
| Change of Gene signature | Study of the transcriptional profile of the blood cells by microarrays | Change from Baseline Gene signature at day after vaccine injection (Day 1) | 
| Humoral immune responses | HAI titers, Individual HAI titers ratio, Subjects with titers ≥ 40, Seroconversion | Day 0, Day 21, Day 90 and Day 210 time |