FDA advisers to weigh composition of COVID vaccines for 2026-2027

• COVID tracking data has deteriorated sharply: the CDC's COVID dashboard currently lacks weekly data due to low sequencing submissions, with the most recent update over a month old showing XFG strains accounted for more than half of U.S. cases through April 11.
• The WHO recommended in early May that manufacturers target either the LP.8.1 strain (currently recommended for 2025-26) or other circulating variants like XFG or NB.1.8.1.
• Four COVID vaccines are approved in the U.S. from Moderna, Pfizer-BioNTech, and Novavax-Sanofi, with the protein-based Novavax shot requiring longer manufacturing time than mRNA-based alternatives.

Summary: FDA Advisory Panel to Review COVID-19 Vaccine Composition for 2026-2027

The FDA's Vaccine and Related Biological Products Advisory Committee will meet Thursday to vote on whether COVID-19 vaccines for the 2026-2027 season should target the dominant XFG variant. The meeting proceeds with no membership changes despite recent vaccine policy disruptions under Health Secretary Robert F. Kennedy Jr.

Key Challenge: FDA staff have raised concerns about limited data availability, as COVID-19 virologic surveillance has declined significantly. The CDC's COVID dashboard currently lacks weekly data due to low sequencing submissions, with the most recent update—now a month old—showing XFG strains accounted for over 50% of U.S. cases in the four weeks ending April 11.

Current Landscape: For the 2025-26 season, the FDA recommended vaccines target LP.8.1, a JN.1 subvariant. However, new subvariants including NB.1.8.1 have emerged since May last year. The WHO has recommended manufacturers target LP.8.1 or other circulating variants like XFG or NB.1.8.1.

Companies Affected: Four COVID vaccines are approved in the U.S.:

• Moderna: mNEXSPIKE and Spikevax (mRNA-based)
• Pfizer-BioNTech: Comirnaty (mRNA-based)
• Novavax-Sanofi: Protein-based vaccine (longer manufacturing timeline)

Market Implications: Reduced surveillance capabilities—due to loss of government staff and decreased academic funding—complicate variant tracking and vaccine development decisions. The protein-based Novavax-Sanofi vaccine faces particular timing challenges given its longer production cycle. The advisory panel's decision will directly impact manufacturing strategies for these vaccine makers heading into the 2026-2027 immunization campaign.