FDA Approves Moderna’s mRNA Flu Vaccine After Phase 3 Success

The FDA approved Moderna’s Biologics License Application (BLA) for its mRNA-based flu vaccine, mRNA-1010 (mFlusiva; Moderna), for adults 50 years and older, supported by a unanimous recommendation from the Vaccines and Related Biological Products Advisory Committee (VRBPAC) and superior efficacy trial data.¹

The approval was based on findings assessing the efficacy and safety of mRNA-1010 in adults between the ages of 50 and 64 years, making it the first mRNA-based flu vaccine.¹ There were 40,805 participants included in the phase 3 (NCT06602024), double-blinded, active-controlled trial, half of whom received mRNA-1010. RT-PCR-confirmed, protocol-defined influenza-like illness was observed in 2% of mRNA-1010 recipients and 2.8% of standard-comparator recipients, corresponding to a relative vaccine efficacy of 26.6% (95% CI, 16.7 to 35.4).²

Solicited adverse reactions occurred more frequently in the mRNA-1010 group when compared with the standard-comparator group, but the overall safety profile of the mRNA-1010 was consistent with earlier findings. There were no new safety concerns identified.^1,2

mRNA Technology Could Improve Seasonal Flu Vaccine Development

The phase 3 trial demonstrated that mRNA-1010 provided greater protection against influenza-like illness compared with the standard-dose comparator vaccine in participants aged 50 years and older.³ These findings demonstrate superior clinical efficacy, as older individuals are more susceptible to severe illness and pneumonia in addition to chronic comorbidities during annual flu seasons.⁴

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

mRNA vaccines are also easily adaptable and thus can be updated to target more recent strains as time continues, which may contribute to improved vaccine efficacy. Additionally, because mRNA vaccines are easier to manufacture, the window for developing a targeted vaccine has been reduced from 6 months to 2–3 months.^2,5

Regulatory Review of mRNA Flu Vaccines Draws National Attention

This approval follows months of scrutiny after the FDA refused to file the initial New Drug Application in mid-February 2026. Moderna’s announcement of the FDA’s refusal-to-file prompted discussions among clinicians and public health officials regarding the regulatory review process for mRNA vaccines. Following discussions, the FDA agreed to review the application ahead of the 2026–2027 influenza season.⁶

The FDA’s initial decision, experts speculate, may have also been influenced by criticism from President Donald J. Trump and HHS Secretary Robert F. Kennedy Jr of mRNA vaccines since the COVID-19 pandemic.³ The approval, however, is still contested by opposing parties, some in favor applauding the success and progress for mRNA vaccines and those against claiming the technology is “just too new.”³

Supporters and opponents of the mRNA-based flu vaccine have presented competing arguments, with supporters pointing to evidence demonstrating the technology's safety, efficacy, and successful administration while also refuting common misconceptions. More than 6 billion doses of COVID-19 mRNA vaccines have been administered globally, with extensive safety monitoring systems finding no evidence that mRNA vaccines alter human DNA—a persistent superstition popular among the general public and those opposed to the mRNA-based flu vaccine.^5,7

The FDA’s initial decision was also overturned after the pharmaceutical company promised to conduct a confirmatory study to provide additional postmarketing data on the vaccine’s safety and effectiveness.⁵

Moderna Approval Comes Amid Shifting Federal mRNA Vaccine Policies

The approval marks the first VRBPAC vaccine review under the Trump administration since 2024, despite President Trump and RFK Jr’s unrelenting criticisms of vaccines.⁵ Additionally, HHS also announced today that the department will begin its upheaval of mRNA vaccine development, halting the research of 22 investigational mRNA vaccines.⁸

The rollback, conducted under the Biomedical Advanced Research and Development Authority, will terminate contracts with Emory University and Tiba Biotech and descoping of mRNA-related work in existing contracts, among other agenda items.

RFK Jr said in a press release that the reason for the rollback is that “these vaccines against upper respiratory infections like COVID and flu” are being discontinued, and that the agency is “shifting that funding toward safer, broader vaccine platforms that remain effective even as viruses mutate.”⁸

Despite controversial opinions opposing the mRNA vaccine, this approval may be a pathway to sway public health officials and the public on the benefits of mRNA vaccines, influencing future vaccine development and public perception surrounding mRNA technology.

References

1. Moderna. Moderna receives U.S. FDA approval for influenza vaccine mFLUSIVA (mRNA-1010). News release. Published August 6, 2026. Accessed August 6, 2026. https://feeds.issuerdirect.com/news-release.html?newsid=4801915282452025&symbol=MRNA

2. Roels IL, Huang G, Ferguson M, et al. Efficacy and safety of an mRNA seasonal influenza vaccine in adults. N Engl J Med. 2026;394:1803-13. doi:10.1056/NEJMoa2516491

3. Inskeep S, Martin M. Primary election results, US missile stockpiles running low, new flu vaccine. Up First from NPR. Published August 5, 2026. Accessed August 5, 2026. https://www.npr.org/2026/08/05/nx-s1-5921135/primary-election-results-us-missile-stockpiles-running-low-new-flu-vaccine

4. National Institute on Aging. Flu and older adults. National Institutes of Health. Updated June 14, 2022. Accessed August 5, 2026. https://www.nia.nih.gov/health/flu/flu-and-older-adults

5. Kim J. Key FDA committee unanimously recommends Moderna's mRNA flu vaccine. NPR. Published June 18, 2026. Accessed August 5, 2026. https://www.npr.org/2026/06/18/nx-s1-5863570/flu-vaccine-mrna-moderna-fda

6. Steinzor P. FDA reverses course, will review Moderna’s mRNA flue vaccine. AJMC^®. February 18, 2026. Accessed August 5, 2026. https://www.ajmc.com/view/fda-reverses-course-will-review-moderna-s-mrna-flu-vaccine

7. Yilma S, Howard J. Anti-vaccine myths rattle health care. Genetic Literacy Project. Published July 29, 2026. Accessed August 5, 2026. https://geneticliteracyproject.org/2026/07/29/anti-vaccine-myths-rattle-health-care/

8. US Department of Health and Human Services. HHS winds down mRNA development under BARDA. Published August 5, 2026. Accessed August 5, 2026. https://www.hhs.gov/press-room/hhs-winds-down-mrna-development-under-barda.html