The U.S. Food and Drug Administration (FDA) refused to consider Moderna’s application for a new flu vaccine using mRNA technology, the company announced Tuesday, a decision that could delay the introduction of a shot designed to offer stronger protection for older adults.

Moderna said it received what’s known as a "refusal-to-file" (RTF) letter from the FDA's Center for Biologics Evaluation and Research (CBER), citing the lack of an "adequate and well-controlled" study with a comparator arm that "does not reflect the best-available standard of care."

Stéphane Bancel, chief executive officer of Moderna, said the FDA's decision did not "identify any safety or efficacy concerns with our product" and "does not further our shared goal of enhancing America’s leadership in developing innovative medicines."

"It should not be controversial to conduct a comprehensive review of a flu vaccine submission that uses an FDA-approved vaccine as a comparator in a study that was discussed and agreed on with CBER prior to starting," Bancel said in a statement. "We look forward to engaging with CBER to understand the path forward as quickly as possible so that America's seniors, and those with underlying conditions, continue to have access to American-made innovations."

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The rare decision from the FDA comes amid increased scrutiny over vaccine approvals under Health Secretary Robert F. Kennedy Jr., who has criticized mRNA vaccines and rolled back certain COVID-19 shot recommendations over the past year.

Kennedy previously removed members of the federal government’s vaccine advisory panel and appointed new members, and moved to cancel $500 million in mRNA vaccine contracts.

The FDA authorized COVID-19 vaccines for the fall for high-risk groups only. Last May, Kennedy announced the vaccines would be removed from the CDC’s routine immunization schedule for healthy children and pregnant women.

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According to Moderna, the refusal-to-file decision was based on the company’s choice of comparator in its Phase 3 trial — a licensed standard-dose seasonal flu vaccine — which the FDA said did not reflect the "best-available standard of care."

Moderna said the decision contradicts prior written communications from the FDA, including 2024 guidance stating a standard-dose comparator would be acceptable, though a higher-dose vaccine was recommended for participants over 65.

Moderna said the FDA "did not raise any objections or clinical hold comments about the adequacy of the Phase 3 trial after the submission of the protocol in April 2024 or at any time before the initiation of the study in September 2024."

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In August 2025, following completion of the Phase 3 efficacy trial, Moderna said it held a pre-submission meeting with CBER, which requested that supportive analyses on the comparator be included in the submission and indicated the data would be a "significant issue during review of your BLA."

Moderna said it provided the additional analyses requested by CBER in its submission, noting that "at no time in the pre-submission written feedback or meeting did CBER indicate that it would refuse to review the file."

The company requested a Type A meeting with CBER to understand the basis for the RTF letter, adding that regulatory reviews are continuing in the European Union, Canada and Australia.

Fox News has reached out to the Department of Health and Human Services for comment.

Fox News Digital's Alex Miller and The Associated Press contributed to this report.

Ashley Farquharson raced to Olympic glory in luge on Tuesday at the 2026 Milan Cortina Olympics.

The American luger became emotional when she checked the scoreboard and realized she earned her first Olympic medal. Her performance in the women's luge singles on Tuesday also marked just the second time an American has won an Olympic medal in the event.

Farquharson, who started sliding as an after-school activity when she was growing up in Park City, Utah, said it was almost hard to believe what she had accomplished.

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"It really didn’t feel real," Farquharson said after her victory. "And then everyone meeting me on the ice, and the whirlwind it’s been since then has really cemented it. For a couple seconds when I was coming up the outrun, I was like, ‘that’s not real.’"

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Germany’s Julia Taubitz took the gold medal, winning by almost a full second, a monster margin in luge. Latvia’s Elena Bota was second, matching her country’s best Olympic result.

Until Farquharson's feat, Erin Hamlin was the last American to earn a bronze medal, doing so at the 2014 Sochi Games.

"This was the dream," Taubitz said. "And now the dream comes true."

Farquharson didn’t medal in any of her first 54 World Cup races before finally breaking through this season.

She wasn’t the fastest, but she was more than good enough. She’s an Olympic medalist. Farquharson’s ability will never be questioned again.

"Super happy for Ashley, very happy for USA Luge," longtime U.S. teammate Emily Fischnaller said. "I mean, we are the ones on the sled, but there’s a team behind us with everything that we do. So, that’s just a testament to all the work that everyone has put into it."

Luge is a sport in which athletes slide on their backs on sleds down an iced track at high speeds.

Fischnaller was 12th for the Americans in 3:33.035, falling from fifth after three runs following trouble in her final heat. Summer Britcher of the U.S., a two-time World Cup race winner this season and now a four-time Olympian, was 14th in 3:33.553.

The Associated Press contributed to this report.

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