The FDA convened an interagency panel to comprise its recommendations for the 2025-2026 flu vaccine composition.
RT’s Three Key Takeaways
- The FDA has recommended virus strains for the 2025-2026 US flu season vaccines, following a review of global surveillance data.
- Different strains were selected for egg-based and cell- or recombinant-based trivalent influenza vaccines to ensure effectiveness.
- The FDA expects an adequate supply of vaccines and does not anticipate any delays in availability for the public.
The FDA made recommendations to vaccine manufacturers for the virus strains to be used in influenza vaccines for the 2025-2026 US flu season, according to an agency news release.
The recommendations were made by an interagency group comprised of scientific and public health experts from the FDA, CDC, and Department of Defense and follow a thorough and comprehensive review of US and global surveillance data, the agency says. The recommendations are similar to the previous year’s strain selection.
This process differs from previous years, however, as the agencies did not include or consult their vaccine advisory boards, the FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) or the CDC’s Advisory Committee on Immunization Practices (ACIP).
Trivalent seasonal influenza vaccines include two influenza A subtype viruses (H1N1 and H3N2) and one influenza type B virus. Influenza virus strains were selected based on the influenza vaccine production method: egg-based and cell- or recombinant-based.
As a result of the meeting with the federal partners, the FDA recommends that the trivalent formulation of egg-based influenza vaccines for the 2025-2026 U.S. influenza season contain the following:
- an A/Victoria/4897/2022 (H1N1)pdm09-like virus;
- an A/Croatia/10136RV/2023 (H3N2)-like virus; and
- a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.
The FDA recommends that the trivalent formulation of cell- or recombinant-based influenza vaccines for the 2025-2026 U.S. influenza season contain the following:
- an A/Wisconsin/67/2022 (H1N1)pdm09-like virus;
- an A/District of Columbia/27/2023 (H3N2)-like virus; and
- a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.
The FDA has informed the manufacturers of FDA-approved seasonal influenza vaccines of these recommendations. The FDA anticipates that there will be an adequate and diverse supply of approved trivalent seasonal influenza vaccines for the 2025-2026 US influenza season.
“Based on this timing, the agency does not anticipate any impact on vaccine supply or timing of availability,” the FDA said in an email.
