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Moderna mRNA flu vaccine US approval

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2026-08-14 23:10 UTC → 2026-08-23 14:37 UTC · added ~~removed~~

In early August 2026, the U.S. Food and Drug Administration (FDA) authorized Moderna’s mRNA-based seasonal influenza vaccine, mFlusiva. On 6 August, the agency granted full approval for adults aged 50–64, based on a late-stage trial involving over 40,000 participants that showed a roughly 27% reduction in flu cases compared to standard vaccines. Adults 65 and older received accelerated approval based on an immunogenicity study, with a confirmatory trial ~~required.~~ required to confirm effectiveness in preventing severe outcomes like hospitalization and death. On 8 August, the FDA issued an emergency use authorization (EUA) for the vaccine, covering adults 50 and older. This action was intended to diversify the U.S. flu-vaccine supply chain and address the high burden of influenza-related hospitalizations and deaths among older adults. The approval process was marked by initial delays, as the FDA had originally declined to review the application due to trial design concerns before reversing its decision following a dispute from Moderna. By 14 August, ~~it was reported that~~ independent advisory committees voted unanimously that the benefits of the vaccine outweigh its risks. The vaccine is expected to be available this fall. The regulatory endorsement of mFlusiva—the first mRNA platform for seasonal influenza in the U.S.—comes amid political scrutiny of the technology. Health and Human Services Secretary Robert F. Kennedy Jr. has criticized mRNA platforms and previously canceled several federal mRNA development projects. Despite these concerns, the vaccine's ability to transition from strain selection to production in two to three months—significantly faster than the six-month cycle for traditional egg-based vaccines—positions it for distribution during the 2026–27 flu season.

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