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The Food and Drug Administration approved Moderna's mRNA-based vaccine against seasonal influenza for people 50 and older, the company said late Wednesday.
It's the first approved vaccine for flu that uses the same technology as COVID-19 shots.
The vaccine is called mFLUSIVA, and Moderna says it will be available "in a few weeks" — in time for the 2026-2027 respiratory virus season in the U.S.
"The FDA approval of mFLUSIVA … demonstrates the continued strength and versatility of our mRNA platform," said Stéphane Bancel, Moderna's chief executive officer, in a statement. "Flu remains a significant public health challenge, and mFLUSIVA provides an important new option for America's seniors. This approval also reflects the ongoing potential of our mRNA platform to help address important public health challenges through continued scientific innovation."
Company research involving more than 40,000 people found that mFLUSIVA is safe and appears to produce stronger protection than traditional flu vaccines.
The FDA's decision was being closely monitored because of the Trump administration's hostility toward mRNA technology.
President Trump embraced mRNA technology during his first term to produce the COVID vaccines, an achievement widely praised as a medical triumph that saved millions of lives.
But the backlash against pandemic responses, including vaccine mandates, led to the vaccines and mRNA technology being vilified by some and becoming the focus of widespread misinformation.
Secretary of Health and Human Services, Robert F. Kennedy Jr., a long-time vaccine critic, has repeatedly condemned the vaccines.
The administration also slashed funding for mRNA vaccine research and curtailed access to the COVID vaccines.
The FDA initially refused to even consider reviewing Moderna's mRNA flu shot. But the agency later relented because of backlash from the pharmaceutical industry and public health experts.
The agency convened a meeting of independent outside advisers in June to consider the vaccine. That panel voted unanimously to recommend the agency approve the new shot.
Many public health officials say the mRNA flu vaccine has other advantages as well.
mRNA vaccines, for example, can be updated and produced much more quickly than standard vaccines.
That could make the vaccine more useful when a new flu strain emerges unexpectedly, which occurred last flu season. It could be especially crucial if a very new flu virus evolves, triggering a flu pandemic.
"I think this is really a critical step forward in advancing influenza vaccine technology," says Michael Osterholm, an infectious disease expert at the University of Minnesota.
Others agree.
"The FDA is signaling openness to this platform, which has been a controversy and an issue," says Dr. Jeanne Marrazzo, chief executive officer of the Infectious Disease Society of America.
"It's a really promising product that could set us up not only for improved response to a bad flu season but also to an improved response to any biological threats."
But critics are disappointed by the decision.
"I really believe that this technology is just too new," says Dr. Brian Hooker, the chief medical officer at Children's Health Defense, an anti-vaccine group once headed by Kennedy. "There has not been the adequate level of study of the implications for, you know, literally everybody. I just feel like the train is leaving the station, and we're not ready yet."
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