WASHINGTON — A federal advisory committee voted unanimously on June 18 to recommend that the FDA clear Moderna’s mRNA-based influenza vaccine, mFLUSIVA, for adults aged 50 and older — casting twin 9–0 votes that position the shot for a potential historic first: the United States’ first licensed mRNA product for seasonal influenza.

The Vaccines and Related Biological Products Advisory Committee (VRBPAC) held two sequential votes. The first asked whether mFLUSIVA’s benefits outweigh its risks for adults aged 50 to 64; the panel answered yes, 9–0. The second posed the identical benefit-risk question for adults 65 and older; the panel again voted 9–0 in favor. VRBPAC votes are advisory only — the FDA is not bound by the committee’s recommendations and will issue its own final determination.

The agency’s target action date under the Prescription Drug User Fee Act (PDUFA) is August 5, 2026. The BLA in question is STN 125869/0.

Moderna is seeking two distinct regulatory approvals under a single filing. For adults 50 to 64, the company pursues traditional, standard approval grounded in clinical efficacy data from the pivotal Phase 3 P304 trial, published in the New England Journal of Medicine. That trial, which enrolled more than 40,000 participants across 11 countries, showed mFLUSIVA reduced RT-PCR–confirmed influenza-like illness by 26.6 percent relative to a standard-dose seasonal comparator; when measured against higher-acuity healthcare outcomes — emergency department visits, hospitalizations, and urgent care — relative vaccine efficacy rose to 47.9 percent.

For adults 65 and older, Moderna seeks accelerated approval, a distinct regulatory pathway that permits licensure on the basis of an immunological surrogate endpoint reasonably likely to predict clinical benefit. Accelerated approval carries a statutory obligation: Moderna must complete a confirmatory Phase IV post-market study — expected to enroll up to 800,000 participants across two flu seasons — to verify and describe the clinical benefit in that age group.

The road to the June 18 hearing was unusually turbulent. On February 3, 2026, CBER Director Vinay Prasad issued a rare refusal-to-file letter, declining to initiate review of the original BLA. Prasad’s stated rationale: Moderna’s pivotal trial used a standard-dose comparator for the 65-and-older cohort rather than the high-dose or adjuvanted vaccines that CDC preferentially recommends for older adults, and therefore the study did not qualify as “adequate and well-controlled.” Moderna pushed back publicly, noting that CBER had accepted the standard-dose comparator in writing roughly 18 months earlier. Within days of the refusal — following public criticism and a formal Type A meeting — the FDA reversed course and agreed to file a revised application. Prasad subsequently left the CBER director role in April 2026.

If the FDA follows VRBPAC’s recommendation and approves the BLA by the August 5 PDUFA date, mFLUSIVA would become the first mRNA vaccine licensed for a routinely recurring, annually updated disease in the United States. Moderna already holds approval for an mRNA COVID-19 vaccine, Spikevax; mFLUSIVA would extend that mRNA platform to influenza. The company has said it is prepared to distribute the vaccine in time for the 2026–2027 flu season.