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# FDA Approves Fluzone High-Dose Quadrivalent
- URL: https://www.fdaweb.com/fda-approves-fluzone-high-dose-quadrivalent/
- Published: 2019-11-07T12:00:00.000Z
- Updated: 2026-09-14T15:52:20.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5145447

FDA has approved a Sanofi supplemental BLA for Fluzone High-Dose Quadrivalent (Influenza Vaccine) for use in adults 65 years of age and older. The vaccine was originally approved in 2009 as a trivalent influenza vaccine, including two influenza A strains and one influenza B strain. The high-dose vaccine now contains an additional influenza B strain.  

Approval was based on data from a Phase 3 immunogenicity and safety study, in which Fluzone High-Dose Quadrivalent achieved the primary endpoint of non-inferior immunogenicity compared to two trivalent formulations of Fluzone High-Dose. “In a secondary endpoint of the trial, each B strain in Fluzone High-Dose Quadrivalent induced a superior immune response compared to the trivalent formulation not containing the corresponding B strain.” the company says.