Study to Assess the Immuno 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 European Adults 60 Years and Older

INTERVENTION: Product Name: quadrivalent influenza vaccine Product Code: 522 Pharmaceutical Form: Suspension for injection in pre‐filled syringe INN or Proposed INN: INFLUENZA VACCINE (SPLIT VIRION, INACTIVATED) Other descriptive name: A/H1N1‐like strain Concentration unit: µg microgram(s) Concentration type: not less then Concentration number: 60‐ INN or Proposed INN: INFLUENZA VACCINE (SPLIT VIRION, INACTIVATED) Other descriptive name: A/H3N2 ‐like strain Concentration unit: µg microgram(s) Concentration type: not less then Concentration number: 60‐ INN or Proposed INN: INFLUENZA VACCINE (SPLIT VIRION, INACTIVATED) Other descriptive name: B/Victoria Lineage Concentration unit: µg microgram(s) Concentration type: not less then Concentration number: 60‐ INN or Proposed INN: INFLUENZA VACCINE (SPLIT VIRION, INACTIVATED) Other descriptive name: B/Yamagata Lineage Concentration unit: µg microgram(s) Concentration type: not less then Concentration number: 60‐ Trade Name: Influvac Tetra Product Name: Influvac Tetra Pharmaceutical Form: Suspension for injection in pre‐filled syringe INN or Proposed INN: INFLUENZA VACCINE (SURFACE ANTIGEN, INACTIVATED) Other descriptive name: A/H1N1‐like strain Concentration unit: µg microgram(s) Concentration type: not less then Concentration number: 15‐ INN or Proposed INN: INFLUENZA VACCINE (SURFACE ANTIGEN, INACTIVATED) Other descriptive name: A/H3N2‐like strain Concentration unit: µg microgram(s) CONDITION: Prevention of influenza infection in adults from 60 years of age and older ; MedDRA version: 20.0 Level: PT Classification code 10022000 Term: Influenza System Organ Class: 10021881 ‐ Infections and infestations Therapeutic area: Diseases [C] ‐ Virus Diseases [C02] SECONDARY OUTCOME: ; Secondary end point(s): ‐ Geometric Mean Titers (GMTs) of influenza vaccine antibodies (pre‐ and post‐vaccination) : Antibody titers will be measured by HAI assay ; ; ‐ Geometric Mean Titers Ratio (GMTR) of influenza vaccine antibodies (post‐/pre‐vaccination) : Antibody titers will be measured by HAI assay ; ; ‐ Percentage of participants with antibody titers = 40 [1/dil] : Antibody titers will be measured by HAI assay ; ; ‐ Percentage of participants achieving serconversion : Influenza vaccine antigens will be measured by HAI assay ; Seroconversion is defined as either a pre‐vaccination titer lower than (<) 10 [1/dil] and a post‐vaccination titer greater than or equal to (=) 40 [1/dil], or a pre‐vaccination titer = 10 [1/dil] and a = 4‐fold increase in post‐vaccination titer ; ; ‐ Percentage of participants reporting solicited injection site reactions and systemic reactions : Injection site reactions: pain, erythema, swelling, induration and ecchymosis ; ; ‐ Geometric Mean Titers Ratio (GMTR) of influenza vaccine antibodies (post‐/pre‐vaccination) : Day 0 (pre‐vaccination) and Day 28 (post‐vaccination) ; ; ‐ Percentage of participants with antibody titers = 40 [1/dil] : Day 28 (post‐vaccination) ; ; ‐ Percentage of participants achieving serconversion : Day 28 (post‐vaccination) PRIMARY OUTCOME: ; Secondary Objective: To further describe the immune response induced by QIV‐HD and QIV‐SD in all subjects by age group, in pooled age groups, and by vaccine group (QIV‐HD; QIV‐SD).; ; To describe the safety profile of all subjects by age group, in pooled age groups, and by vaccine group (QIV‐HD; QIV‐SD).; Main Objective: To demonstrate that QIV‐HD induces an immune response that is superior to the responses induced by QIV‐SD for all 4 virus strains 28 days post‐vaccination in subjects 60 to 64 years of age and in subjects 65 years of age and older. Primary end point(s): Geometric Mean Titers (GMTs) of influenza vaccine antibodies (post‐vaccination) : Antibody titers will be measured by hemagglutination inhibition (HAI) assay Timepoint(s) of evaluation of this end point: Day 28 (post‐vaccination) ; Systemic reactions: fever, headache, malaise, myalgia and shivering; ; Timepoint(s) of evaluation of this end point: ‐ Geometric Mean Titers (GMTs) of influenza vaccine antibodies (pre‐ and post‐vaccination) : Day 0 (pre‐vaccination) and Day 28( post‐vaccination) ; ; ‐ Percentage of participants reporting solicited injection site reactions and systemic reactions : Within 7 days post‐vaccination ; INCLUSION CRITERIA: ‐ Sixty years of age and older on the day of inclusion ‐ Able to attend all scheduled visits and to comply with all trial procedures Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range 770 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 770