The aim of the trial is to evaluate immunogenicity and safety of the quadrivalent influenza vaccine (QIV) and the trivalent influenza vaccine (TIV) (split-virion inactivated) Northern Hemisphere (NH) 2015 2016 seasonal formulations, in subjects aged 18 to 60 years in the Republic of Korea for the registration of the QIV by the Ministry of Food and Drug Safety.

Objectives:

• To evaluate the immunogenicity of QIV and TIV (split-virion, inactivated) NH 2015-2016 seasonal formulations. The compliance, in terms of immunogenicity, of the QIV NH 2015-2016 formulation, with the requirements of the Committee for Medicinal Products for Human Use (CHMP) Note for Guidance (NfG) CPMP/BWP/214/96 will be assessed.
• To evaluate the safety profile of QIV and TIV (split-virion, inactivated) NH 2015-2016 seasonal formulations

All subjects will receive one dose of either QIV or TIV on Day 0. They will be monitored for safety and immunogenicity for up to Day 21 post-vaccination.

Inclusion Criteria:

• Aged 18 to 60 years on the day of inclusion
• Subjects aged 18 years: Assent form has been signed and dated by the subject or by an independent witness, and informed consent form has been signed and dated by at least one parent or another legally acceptable representative or by an independent witness Subjects aged 19 to 60 years: Informed consent form has been signed and dated by the subject or by an independent witness
• Subject and parent/legally acceptable representative (if applicable) are able to attend all scheduled visits and to comply with all trial procedures

Exclusion Criteria:

• Subject is pregnant, or lactating, or of childbearing potential (to be considered of non-childbearing potential, a female must be pre-menarche or post-menopausal for at least 1 year, surgically sterile, or using an effective method of contraception or abstinence from at least 4 weeks prior to vaccination and until at least 3 weeks after vaccination)
• Participation at the time of study enrollment (or in the 4 weeks preceding the trial vaccination) or planned participation during the present trial period in another clinical trial investigating a vaccine, drug, medical device, or medical procedure
• Receipt of any vaccine in the 4 weeks preceding the trial vaccination or planned receipt of any vaccine until the second visit, 3 weeks following the trial vaccination
• Vaccination against influenza if administered in the context of a clinical trial or a flu vaccination campaign or self-reported history of influenza infection (influenza-like illness) in the previous 6 months
• 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 history of seropositivity for Human Immunodeficiency Virus (HIV) or Hepatitis C
• Known systemic hypersensitivity to eggs, chicken proteins, neomycin, formaldehyde and octoxynol-9, or 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
• Known or suspected thrombocytopenia, contraindicating intramuscular vaccination, based on Investigator's judgment
• Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating intramuscular vaccination, based on Investigator's judgment
• Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily
• Current alcohol abuse or drug addiction
• Chronic illness that, in the opinion of the investigator, is 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 ≥ 38.0°C). A prospective subject should not be included in the study until the condition has resolved or the febrile event has subsided
• 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, natural or adopted child) of the Investigator or employee with direct involvement in the proposed study.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org