The US Food and Drug Administration (FDA) has approved Fluzone (Sanofi) high-dose quadrivalent influenza vaccine for adults aged 65 years and older. This approval is the final step toward the company's complete transition from trivalent to quadrivalent influenza vaccines in the US, Sanofi said in a news release. Fluzone high-dose quadrivalent influenza vaccine will be available for the 2020–2021 influenza season. The trivalent formulation will be available through the end of the 2019–2020 influenza season. The FDA approved Sanofi's trivalent version of Fluzone in 2009, which contains two influenza A strains and one influenza B strain. The quadrivalent version contains an additional influenza B strain. "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," David Loew, Sanofi executive vice president and head of Sanofi Pasteur, said in the release. In a phase 3 immunogenicity and safety study, the quadrivalent vaccine achieved the primary endpoint of non-inferior immunogenicity compared with two trivalent formulations of Fluzone high-dose, each containing one of the two influenza B strains recommended for inclusion in the vaccine for the 2017–2018 influenza season, the company said. In a secondary endpoint of the trial, each B strain in the Fluzone high-dose quadrivalent vaccine induced a superior immune response compared to the trivalent formulation not containing the corresponding B strain, according to the company. Rates of local and systemic reactions following immunization with the Fluzone high-dose quadrivalent vaccine were similar to those seen with the trivalent formulations of Fluzone high-dose. The most common reactions are injection-site pain (41%), myalgia (23%), headache (14%), and malaise (13%). Most reactions started within the first 3 days of vaccination and typically resolved within 3 days of vaccination. Results of the study were published in the journal Vaccine in September. The Centers for Disease Control and Prevention (CDC) continues to recommend routine yearly influenza vaccination for everyone aged 6 months or older who has no contraindications. Source
