Study to Assess the Immune Response and the Safety Profile of a High-Dose Quadrivalent Influenza Vaccine (QIV-HD) Compared to a Standard-Dose Quadrivalent Influenza Vaccine (QIV-SD) in Taiwanese Adults 65 Years of Age and Older

Study Overview
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Brief Summary
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Primary Objective: Immunogenicity: To describe the immune response induced by high-dose quadrivalent influenza vaccine (QIV-HD) and AdimFlu-S (QIS) by hemagglutinin inhibition (HAI) measurement method in all participants. Safety: To describe the safety profile of all participants in each study groups.

Detailed Description
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The duration of each participant's participation was approximately 28 days (Day 0 through Day 28 [+ 7 days]).

Official Title
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Immunogenicity and Safety of a High-Dose Quadrivalent Influenza Vaccine in Subjects 65 Years of Age and Older in Taiwan

Conditions
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Influenza (Healthy Volunteers)

Intervention / Treatment
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* Biological: High-Dose Quadrivalent Influenza Vaccine
* Biological: Standard-Dose Quadrivalent Influenza Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion criteria : 65 years and older on the day of inclusion. Able to attend all scheduled visits and complied with all study procedures. Exclusion criteria: Participation at the time of study enrollment (or in the 4 weeks preceding the study vaccination) or planned participation during the study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure. Receipt of any vaccine in the 4 weeks (28 days) preceding the study vaccination or planned receipt of any vaccine prior to Visit 2. Previous vaccination against influenza (in the preceding 6 months) with either the study vaccine or another vaccine. Receipt of immune globulins, blood or blood-derived products in the past 3 months. Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months). Known systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccine(s) used in the study or to a vaccine containing any of the same substances. Thrombocytopenia, bleeding disorder, or receipt of anticoagulants that based on Investigator's judgment contraindicate intramuscular vaccination. Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily. Alcohol, prescription drug, or substance abuse that, in the opinion of the Investigator, might interfere with the study conduct or completion. Chronic illness that, in the opinion of the investigator, was at a stage where it might interfere with trial conduct or completion. Moderate or severe acute illness/infection (according to investigator judgment) on the day of vaccination or febrile illness (temperature greater than or equal to [>=] 38.0 degree Celsius). A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided. Personal or family history of Guillain-Barré syndrome. Neoplastic disease or any hematologic malignancy (except localized skin or prostate cancer that was stable at the time of vaccination in the absence of therapy and participants who had a history of neoplastic disease and had been disease free for >=5 years). Identified as an Investigator or employee of the Investigator or study center with direct involvement in the proposed study, or identified as an immediate family member (i.e., parent, spouse) of the Investigator or employee with direct involvement in the proposed study. The above information was not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group 1: High-Dose Quadrivalent Influenza Vaccine (QIV-HD)<br>Participants received a single injection of 0.7 milliliters (mL) QIV-HD, intramuscularly (IM) at Day 0. | Biological: High-Dose Quadrivalent Influenza Vaccine<br>* Pharmaceutical form: Suspension for injection in pre-filled syringe, Route of administration: IM<br>* Other names: Fluzone® High Dose, Efluelda™;|
| Active Comparator: Group 2: Standard-Dose Quadrivalent Influenza Vaccine (QIV-SD)<br>Participants received a single injection of 0.5 mL QIV-SD, IM at Day 0. | Biological: Standard-Dose Quadrivalent Influenza Vaccine<br>* Pharmaceutical form: Suspension for injection in pre-filled syringe, Route of administration: IM<br>* Other names: AdimFlu-S (QIS);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Geometric Mean Titers (GMTs) of Influenza Vaccine Antibodies at Day 0 | GMTs of anti-influenza antibodies were measured using hemagglutination inhibition (HAI) assay for 4 influenza virus strains: A/H1N1, A/H3N2, B1 (B Victoria Lineage), and B2 (B Yamagata Lineage). Titers were expressed in terms of 1/dilution. | Day 0 (pre-vaccination) | 
| Geometric Mean Titers of Influenza Vaccine Antibodies at Day 28 | GMTs of anti-influenza antibodies were measured using HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B1 (B Victoria lineage), and B2 (B Yamagata lineage). Titers were expressed in terms of 1/dilution. | Day 28 (post-vaccination) | 
| Geometric Mean Titers Ratio (GMTR) of Influenza Vaccine Antibodies | GMTRs of anti-influenza antibodies were measured by using HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B1 (B Victoria lineage), and B2 (B Yamagata lineage). GMTRs were calculated as the ratio of GMTs post-vaccination (on Day 28) and pre-vaccination (on Day 0). | Day 0 (pre-vaccination), Day 28 (post-vaccination) | 
| Percentage of Participants Achieving Seroconversion Against Influenza Virus Antigens | Anti-influenza antibodies were measured by HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B1 (B Victoria lineage), and B2 (B Yamagata lineage). Seroconversion was defined as either a pre-vaccination HAI titer less than (<) 10 (1/dilution) at Day 0 and a post-vaccination titer greater than or equal to (>=) 40 (1/dilution) at Day 28 or a pre-vaccination titer >=10 (1/dilution) at Day 0 and a >= four-fold increase in post-vaccination titer at Day 28. | Day 28 (post-vaccination) | 
| Percentage of Participants With Antibody Titers >=40 (1/Dilution) at Day 0 | Antibody titer was measured by using HAI assay method for 4 influenza virus strains: A/H1N1, A/H3N2, B1 (B Victoria lineage), and B2 (B Yamagata lineage). | Day 0 (pre-vaccination) | 
| Percentage of Participants With Antibody Titers >=40 (1/Dilution) at Day 28 | Antibody titer was measured using HAI assay method for 4 influenza virus strains: A/H1N1, A/H3N2, B1 (B Victoria lineage), and B2 (B Yamagata lineage). | Day 28 (post-vaccination) | 
| Number of Participants With Immediate Unsolicited Systemic Adverse Events (AEs) | An AE was any untoward medical occurrence in a patient or in a clinical investigation participant administered a medicinal product and which did not had any causal relationship with the treatment. An unsolicited AE was an observed AE that did not fulfill the conditions prelisted in the case report book (CRB) in terms of diagnosis and/or onset window post-vaccination. All participants were observed for 30 minutes after vaccination, and any unsolicited systemic AEs occurred during that time were recorded as immediate unsolicited AEs in the CRB. | Within 30 minutes post-vaccination | 
| Number of Participants With Solicited Injection Site and Systemic Reactions | A solicited reaction was an expected adverse reaction (sign or symptom) observed and reported under the conditions (nature and onset) prelisted (i.e., solicited) in the protocol and CRB and considered as related to the product administered. Solicited injection site reactions included pain, erythema, swelling, induration, and bruising. Solicited systemic reactions included fever, headache, malaise, myalgia and shivering. | Within 7 days post-vaccination | 
| Number of Participants With Unsolicited Adverse Events | An AE was any untoward medical occurrence in a patient or in a clinical investigation participant administered a medicinal product and which did not had any causal relationship with the treatment. An unsolicited AE was an observed AE that did not fulfill the conditions prelisted in the CRB in terms of diagnosis and/or onset window post-vaccination. | Within 28 days post-vaccination | 
| Number of Participants With Serious Adverse Events (SAEs) Including Adverse Event of Special Interest (AESIs) | An SAE was any untoward medical occurrence that at any dose resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or was an important medical event. AESIs was defined as event for which ongoing monitoring and rapid communication by the investigator to the sponsor was done. | From Day 0 up to 28 days post-vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Influenza