The U.S. Food and Drug Administration has approved Moderna's mRNA influenza vaccine, making it the first flu shot based on messenger RNA technology to receive regulatory clearance in the United States. The approval marks a major expansion of mRNA vaccine technology, which first gained widespread use during the COVID-19 pandemic.

Moderna developed the vaccine using the same platform that underpinned its highly effective COVID-19 shots. Proponents of the technology argue that mRNA vaccines can be updated more rapidly in response to evolving flu strains than traditional egg-based formulations, potentially improving year-to-year effectiveness.

Traditional influenza vaccines are typically manufactured using chicken eggs, a process that can take months and may reduce effectiveness if the selected strains drift before the season begins. The mRNA approach allows for faster reformulation, which public health officials have long sought as a way to better match vaccines to circulating viruses.

The FDA's decision follows clinical trials evaluating the vaccine's safety and efficacy. Regulators reviewed data on immune response and adverse events before granting approval. The agency's action clears the way for Moderna to distribute the vaccine commercially for the 2026–2027 flu season.

The approval comes as health authorities continue efforts to increase flu vaccination rates across the country. Influenza causes tens of thousands of deaths in the United States annually, and health officials have emphasized that broader vaccine uptake remains a critical public health goal regardless of which formulation individuals choose.