Safety and Immunogenicity of Fluzone® Quadrivalent Vaccine Administered to Healthy Children

All participants received 1 intramuscular dose of Fluzone Quadrivalent vaccine during Visit 1. For participants, for whom 2 doses of influenza vaccine were recommended per Advisory Committee on Immunization Practices (ACIP) guidance, a second dose of Fluzone Quadrivalent vaccine (of the same volume as the first dose) was administered during Visit 2 (28 days after Visit 1).

Solicited adverse event (AE) information was collected for 7 days after each vaccination, unsolicited AE information was collected from Visit 1 to Visit 2 or to Visit 3 for participants receiving 2 doses of study vaccine. Serious adverse event (SAE) information was collected for 28 days after each vaccination.

Immunogenicity was evaluated in a planned subset of 1600 randomly selected participants prior to vaccination on Day 0 (Visit 1) and at Day 28 after the final vaccination.

Inclusion criteria

• Aged 6 to < 36 months of age on the day of first study vaccination (study product administration).
• Born at full term of pregnancy (≥37 weeks) and/or with a birth weight ≥2.5 kg. Note: This inclusion criterion only applies to participants 6 to <12 months of age on the day of the first study visit.
• Informed consent form has been signed and dated by the parent(s) or guardian(s).
• Participant and parent/guardian are able to attend all scheduled visits and to comply with all trial procedures.

Exclusion criteria

• Participation at the time of study enrollment (or in the 30 days preceding the first 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 30 days preceding the first trial vaccination, or planned receipt of any vaccine before Visit 2 for participants receiving 1 dose of influenza vaccine or Visit 3 for participants receiving 2 doses of influenza vaccine.
• Previous vaccination against influenza (in the 2016-2017 season) with either the trial 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 used in the trial or to a vaccine containing any of the same substances.
• Thrombocytopenia, which may be a contraindication for intramuscular vaccination, at the discretion of the Investigator.
• Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating intramuscular vaccination.
• Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily.
• 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 planned vaccination or febrile illness (temperature ≥100.4 degrees Fahrenheit [38.0 degrees Celsius]). A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided.
• Identified as a natural or adopted child of either the Investigator or an employee with direct involvement in the proposed study.
• History of serious adverse reactions to any influenza vaccine.
• Personal history of Guillain-Barré syndrome.
• Any condition that in the opinion of the Investigator would pose a health risk to the participant if enrolled or could interfere with the evaluation of the vaccine.
• Personal history of clinically significant developmental delay (at the discretion of the Investigator), neurologic disorder, or seizure disorder.
• Known seropositivity for human immunodeficiency virus, hepatitis B, or hepatitis C.