FDA Approves First mRNA-Based Influenza Vaccine From Moderna for Adults Aged 50 and Older

WASHINGTON — The U.S. Food and Drug Administration has approved the first messenger RNA-based vaccine for seasonal influenza, clearing Moderna's mFLUSIVA for use in adults 50 years and older, the company announced this week.

The approval, granted Wednesday, marks a milestone for mRNA technology beyond its established use in COVID-19 vaccines. mFLUSIVA received traditional approval for adults ages 50 to 64 and accelerated approval for those 65 and older. Moderna has committed to a postmarketing study to confirm clinical benefit in the older age group.

"Flu remains a significant public health challenge, and mFLUSIVA provides an important new option for America's seniors," Moderna Chief Executive Officer Stéphane Bancel said in a statement. "This approval also reflects the ongoing potential of our mRNA platform to help address important public health challenges through continued scientific innovation."

The decision followed a unanimous recommendation in June from the FDA's Vaccines and Related Biological Products Advisory Committee. The panel concluded that the benefits of the vaccine outweighed its risks for adults 50 and older.

Approval for the 50-to-64 age group rests on results from a large Phase 3 trial that enrolled more than 40,000 adults across 11 countries. In that study, known as Fluent, mFLUSIVA demonstrated 26.6 percent relative vaccine efficacy compared with a licensed standard-dose influenza vaccine. Among participants 65 and older in the same trial, relative efficacy was 27.4 percent. Most adverse reactions were mild to moderate and temporary, including injection-site pain, fatigue and headache. Serious adverse event rates were similar between the mRNA vaccine and the comparator.

For adults 65 and older, the accelerated approval was supported by a separate Phase 3 study showing stronger antibody responses than a high-dose influenza vaccine. Confirmation of clinical effectiveness in this group will come from the required follow-up study.

Moderna said it expects supplies of mFLUSIVA to become available at select retailers in the coming weeks, in time for the 2026-2027 respiratory virus season. The vaccine will join the company's existing U.S. portfolio, which includes Spikevax and mNEXSPIKE for COVID-19 and mRESVIA for respiratory syncytial virus.

Seasonal influenza continues to impose a substantial public health burden. The Centers for Disease Control and Prevention has estimated tens of thousands of deaths in the United States in recent severe seasons, with older adults facing the highest risk of serious complications, hospitalization and death. Traditional egg-based and recombinant vaccines have long been the mainstay of prevention, but their effectiveness can vary from year to year depending on how well the selected strains match circulating viruses.

mRNA technology offers potential advantages in manufacturing speed and adaptability. Traditional flu vaccine production often begins months in advance based on predictions of circulating strains. mRNA platforms can be updated more rapidly once a new strain is identified, a capability that public health experts have long sought for influenza.

The path to approval was not without complications. Earlier this year the FDA initially declined to review Moderna's application, citing concerns about the trial design. The agency later reversed that decision and accepted the filing. The subsequent advisory committee review and final approval proceeded on the basis of the submitted clinical data.

mFLUSIVA is a trivalent vaccine targeting influenza A/H1N1, A/H3N2 and B/Victoria strains. It will compete in a crowded market that includes products from Sanofi, GSK, CSL Seqirus and AstraZeneca. Pricing details were not immediately disclosed.

For older adults, who often receive high-dose or adjuvanted formulations to compensate for age-related declines in immune response, the availability of an additional option with demonstrated relative efficacy and immunogenicity data is expected to expand choices for clinicians and patients. Public health authorities continue to recommend annual vaccination for this population as the most effective way to reduce severe disease.

The approval represents Moderna's fourth product cleared by the FDA and the first mRNA influenza vaccine authorized in the United States. The company has pursued a broader pipeline of mRNA candidates targeting other infectious diseases and has highlighted the platform's versatility in repeated communications with investors and regulators.

As the 2026-2027 season approaches, attention will turn to uptake among eligible adults, real-world effectiveness data and the results of the confirmatory study in those 65 and older. Health officials and clinicians will also monitor how the new vaccine fits into existing immunization recommendations and whether its manufacturing flexibility translates into improved strain matching in future seasons.

Influenza remains a leading cause of vaccine-preventable illness among older adults. The introduction of an mRNA-based option adds a new tool grounded in clinical evidence of superior relative performance against standard-dose vaccines in the studied population. Moderna has stated that supply will be available for the upcoming season, positioning the product for use alongside other authorized flu vaccines this fall and winter.

The regulatory clearance closes a multiyear development effort and underscores the continued evolution of vaccine platforms more than five years after mRNA technology first entered widespread use during the COVID-19 pandemic. For adults 50 and older, the decision provides a newly authorized choice backed by large-scale trial data and the endorsement of the FDA's independent advisory committee.