The Food and Drug Administration (FDA) has approved the supplemental Biologics License Application (sBLA) for Fluzone High-Dose Quadrivalent (Influenza Vaccine; Sanofi Pasteur) for active immunization for the prevention of influenza disease in patients aged ≥65 years. 

Fluzone High-Dose Quadrivalent is an inactivated influenza vaccine for intramuscular administration that contains 2 influenza A strains and 2 influenza B strains. The approval was based on data from a phase 3, active-controlled, double-blind study that compared the immunogenicity and safety of Fluzone High-Dose Quadrivalent to Fluzone High-Dose (trivalent formulation) in patients aged ≥65 years (N=2670). Patients were randomized 4:1:1 to receive either one dose of Fluzone High-Dose Quadrivalent, or 1 of 2 formulations of Fluzone High-Dose. The co-primary end points were geometric mean antibody titers (GMTs) and seroconversion rates at Day 28 post-vaccination.

Results showed noninferior immunogenicity with Fluzone High-Dose Quadrivalent when compared with Fluzone High-Dose. Moreover, Fluzone High-Dose Quadrivalent generated a superior immune response to each B strain compared with the immune response generated by the formulation of Fluzone High-Dose that did not contain the additional B strain.

Regarding safety, the most common adverse reactions were injection-site pain, myalgia, headache and malaise. Fluzone High-Dose Quadrivalent is contraindicated for use in patients with severe allergic reactions to any component of the vaccine, including egg protein.

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“Increasing protection and delivering improved influenza vaccines are critical to public health,” said David Loew, Sanofi Executive VP and head of Sanofi Pasteur. “We are excited to build upon the success of trivalent Fluzone High-Dose with this FDA approval to expand protection for an additional B strain.”

Fluzone High-Dose Quadrivalent will be made available during the 2020-2021 influenza season as a 0.7mL single-dose, prefilled syringe. Fluzone High-Dose will continue to be available during the 2019-2020 flu season.

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