Study to Evaluate the Effectiveness of a High-Dose Quadrivalent Influenza Vaccine (QIV-HD) Compared to a Standard-Dose Quadrivalent Influenza Vaccine (QIV-SD) in Adults 65 Years of Age and Older
Condition: Influenza (Healthy Volunteers)
MeSH terms: Influenza, Human
Intervention: Quadrivalent Influenza Vaccine (split virion, inactivated) High-Dose (QIV-HD); Standard-Dose Inactivated Influenza Vaccine Quadrivalent, Northern Hemisphere strains (QIV-SD)
Intervention description: Pharmaceutical form: Suspension for injection in pre-filled syringe Route of administration: Intramuscular; Pharmaceutical form: Suspension for injection in pre-filled syringe Route of administration: Intramuscular
Intervention MeSH terms: Vaccines
Phase: Phase 3
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Masking description: Modified double-blind: the participants, the outcome assessors in the hospitals and outpatient care, the Investigators, and the Sponsor will remain blinded to the vaccine assignment in order to avoid any bias in reporting and evaluating illnesses or SAEs. An unblinded qualified trial staff member will administer the appropriate vaccine.
Enrollment: 33096.0
Sex: All
Minimum age: 65 Years
Healthy volunteers: Accepts Healthy Volunteers

Summary:

      Primary Objective:

      To demonstrate the superior relative effectiveness of QIV-HD as compared to QIV-SD among
      persons 65 years of age and older for the prevention of cardiovascular and/or respiratory
      hospitalizations.

      Secondary Objective:

        -  To assess the clinical relative effectiveness of QIV-HD as compared to QIV-SD in
           prevention of:

        -  inpatient hospitalization for selected circulatory and respiratory causes

        -  death, either all-cause or cardiovascular or respiratory causes

        -  inpatient hospitalization (using primary and secondary discharge diagnoses)

        -  inpatient hospitalization (using admission diagnoses)

        -  hospital emergency room visits

        -  primary care visits to physician or

        -  major acute cardiovascular events (MACE)

        -  To assess the characteristics of inpatient hospitalization or hospital emergency room
           visits or primary care visits to physician by QIV-HD and QIV-SD groups.

        -  To describe the clinical relative effectiveness of QIV-HD as compared to QIV-SD:

        -  by age group and by group with specific comorbidities

        -  for different periods of observation

        -  To describe all serious adverse events (SAEs) (including adverse event of special
           interest [AESIs]) for all subjects in both QIV-HD and QIV-SD groups.
    

Eligibility criteria:

        Inclusion criteria:

        - Aged 65 years or older on the day of inclusion ("65 years" means from the day of the 65th
        birthday).

        Exclusion criteria:

          -  Participation at the time of study enrollment (or in the 4 weeks [28 days] preceding
             the study vaccination) or planned participation during the present study period in
             another clinical study investigating a vaccine, drug, medical device, or medical
             procedure.

          -  Previous vaccination against influenza (in the preceding 6 months) with either the
             study vaccines or another vaccine.

          -  Known systemic 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.

        The above information was not intended to contain all considerations relevant to a
        participant's potential participation in a clinical trial.