FDA Panel Backs Moderna mRNA Flu Vaccine For Older Adults
FDA's Vaccines and Related Biological Products Advisory Committee unanimously recommended Moderna's mRNA seasonal flu vaccine, mFlusiva, for adults 50 and older on Thursday, June 18, 2026, advancing it toward possible FDA approval.[1]
Advisers said they saw no credible safety signals and emphasized that the mRNA does not enter the cell nucleus, interact with DNA, or persist in the body.[1] Researchers at Washington University in St. Louis analyzed 75 trial participants and found mFlusiva induced longer-lasting antibody responses that recognized more flu strains than standard vaccines.[1] VRBPAC member Dr. Anna Durbin and former FDA biologics chief Dr. Jesse Goodman said Moderna ran a full, standard phase 3 efficacy program in tens of thousands of people with no shortcuts.[1]
Moderna submitted a biologics license application for its mRNA-1010 seasonal influenza candidate, later named mFlusiva, early in 2026. On February 11, 2026, the FDA issued a refuse-to-file letter, saying the pivotal phase 3 trial was not adequate and well-controlled. The agency said the trial used a standard-dose comparator instead of the best-available standard of care for adults 65 and older. Moderna revised its application to seek full approval for ages 50 to 64 and accelerated approval for those 65 and older. The FDA accepted the revised filing on February 18, 2026 and set an August 5 decision target.
The recommendation arrives against a political backdrop in which HHS Secretary Robert F. Kennedy Jr. pulled back nearly $500 million in mRNA vaccine development contracts in 2025.[1] Moderna's phase 3 P304 trial found 26.6% relative vaccine efficacy against RT-PCR-confirmed influenza-like illness versus standard-dose vaccines in adults 50 and older, with consistent results across A/H1N1, A/H3N2, and B/Victoria strains. About 125.5 million U.S. adults were projected to be age 50 or older in 2026, underscoring the shot's potential reach. Social media reaction noted the unanimous vote while some commentators questioned the reversal from the earlier FDA refuse-to-file decision.
The mainstream summary does not mention the specific relative vaccine efficacy rates reported from Moderna's phase 3 trial, which found a 26.6% relative efficacy against RT-PCR-confirmed influenza-like illness, with notable performance across various flu strains: 29.6% for A/H1N1, 22.2% for A/H3N2, and 29.1% for B/Victoria. These details underscore the vaccine's potential effectiveness, particularly for older adults, and highlight the nuanced data that informs the advisory committee's recommendation. Additionally, the summary overlooks the significant political context surrounding the vaccine's approval process, particularly the earlier FDA refuse-to-file letter that questioned the adequacy of Moderna's trial design, which was later addressed by revising the application to focus on a younger age group while seeking accelerated approval for those 65 and older. This shift reflects the complex interplay between regulatory scrutiny and the urgent need for effective vaccines in the older population, a point emphasized by the unanimous vote despite past hesitations and external pressures on vaccine development funding.[2][3]
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📊 Relevant Data
Moderna's phase 3 trial (P304) found its mRNA flu vaccine achieved 26.6% relative vaccine efficacy (95% CI: 16.7%-35.4%) against RT-PCR-confirmed influenza-like illness compared to standard-dose vaccines in adults aged 50 and older, with consistent results across strains (A/H1N1: 29.6%; A/H3N2: 22.2%; B/Victoria: 29.1%) and 27.4% rVE in those 65 and older.
Efficacy and safety of an mRNA seasonal influenza vaccine in adults — New England Journal of Medicine
Approximately 125.5 million adults aged 50 and older live in the United States as of 2026.
Number of adults aged 50 and older — IBISWorld
📌 Key Facts
- On Thursday, June 18, 2026, FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) held its first full review of a new vaccine application since 2023 and voted unanimously to recommend Moderna's mRNA flu vaccine mFlusiva for adults 50 and older.
- Moderna and FDA reviewers reported no credible safety signals during the advisory-committee review and emphasized that the mRNA does not enter the cell nucleus, interact with DNA, or persist in the body.
- Researchers at Washington University in St. Louis analyzed responses from 75 trial participants and concluded that mFlusiva induced longer-lasting antibody responses that recognized more flu strains than standard vaccines, helping explain its superior performance.
- VRBPAC member Dr. Anna Durbin said Moderna ran a full, standard phase 3 efficacy program in tens of thousands of people with no shortcuts, a point reinforced by former FDA biologics chief Dr. Jesse Goodman about the robustness of the dataset.
- The recommendation comes against a political backdrop in which HHS Secretary Robert F. Kennedy Jr. previously pulled back nearly $500 million in mRNA vaccine development contracts in 2025.
📰 Source Timeline (2)
Follow how coverage of this story developed over time
- On Thursday, June 18, 2026, FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) held its first full review of a new vaccine application since 2023 and voted unanimously to recommend Moderna's mRNA flu vaccine mFlusiva for adults 50 and older.
- The article details that HHS Secretary Robert F. Kennedy Jr. previously pulled back nearly $500 million in mRNA vaccine development contracts in 2025, setting a political backdrop for this recommendation.
- Researchers from Washington University in St. Louis analyzed responses from 75 trial participants and found that mFlusiva induced longer-lasting antibody responses that recognized more flu strains than standard vaccines, helping explain its superior performance.
- Moderna and FDA reviewers reported no credible safety signals in the advisory-committee review and emphasized that the mRNA does not enter the cell nucleus, interact with DNA, or persist in the body.
- VRBPAC member Dr. Anna Durbin stated that Moderna ran a full, standard phase 3 efficacy program in tens of thousands of people with no shortcuts, and former FDA biologics chief Dr. Jesse Goodman is cited reinforcing the robustness of the dataset.