FDA Reverses Course, Will Review Moderna’s mRNA Flu Vaccine

Lead

On Feb. 18, 2026, Moderna said the U.S. Food and Drug Administration reversed a recent refusal and agreed to review the company’s influenza vaccine that uses messenger RNA (mRNA) technology. The agency had rejected the application last week, citing flaws in the study design, but resumed talks and accepted the submission for formal review. Moderna split its filing by age group — seeking standard approval for people 50–64 and an accelerated pathway for those 65 and older — and agreed to a post-market study for the older cohort. The FDA set an August 2026 deadline for a decision; if authorized, the vaccine could be available for older adults during the 2026–27 flu season.

Key Takeaways

• The FDA initially denied Moderna’s application last week, citing shortcomings in the trial design but has now agreed to review the revised submission (announced Feb. 18, 2026).
• Moderna split its application by age: traditional approval sought for ages 50–64, accelerated approval sought for ages 65+ with a committed post-market study for the latter group.
• The FDA set an August 2026 target date to complete its review and reach a decision on authorization.
• If authorized, the vaccine — developed with mRNA technology — could be available to older adults for the upcoming 2026–27 influenza season.
• Health Secretary Robert F. Kennedy Jr. has publicly criticized mRNA vaccines, and federal policy changes over the past year have curtailed some mRNA research and funding, including cancellations totaling hundreds of millions of dollars.
• Moderna’s manufacturing footprint includes a production site in Laval, Quebec, which has been cited in company materials as part of its supply network.

Background

mRNA vaccine platforms rose to global prominence with the COVID-19 vaccines in 2020, demonstrating rapid development cycles and high efficacy in many populations. The technology instructs cells to produce a harmless fragment of a virus antigen, prompting an immune response; public health authorities have generally described the approach as safe based on available evidence from COVID-19 vaccine programs.

In the U.S., regulatory scrutiny of novel vaccine applications intensified after the pandemic, with agencies applying established standards for trial design and endpoints. Over the last year, policy shifts under the Department of Health and Human Services leadership have reduced some federal support for mRNA projects, and officials have tightened recommendations for certain COVID vaccine uses.

Seasonal influenza vaccine approvals typically rely on established pathways tied to demonstration of immunogenicity and safety in target age groups. Companies can pursue accelerated approval for older adults when trials are designed to show surrogate endpoints reasonably likely to predict clinical benefit, usually accompanied by commitments to follow-up studies after market entry.

Main Event

Moderna announced on Feb. 18, 2026, that after further discussions with regulators the FDA would accept the company’s application for its mRNA flu vaccine. The agency had rejected the submission the previous week, saying the study design did not meet its requirements. According to Moderna, the firm split its filing so that adults 50–64 would be considered under a standard approval pathway while adults 65 and older would be considered under accelerated approval.

As part of the accelerated pathway for the 65-plus group, Moderna agreed to conduct an additional post-authorization study studying clinical outcomes in that population once the vaccine is on the market. The company and regulators also discussed elements of trial design and statistical analysis that the FDA had flagged in its initial review.

The FDA set a target of August 2026 to reach a decision, a timeline Moderna said would allow for distribution to older adults ahead of the 2026–27 flu season if authorization is granted. Production capacity for the vaccine includes Moderna’s Laval, Quebec facility, cited by the company as part of its manufacturing network.

Analysis & Implications

Regulatory reversal in this case highlights the negotiating space between developers and the FDA on study endpoints and statistical approaches. An August decision timeline gives regulators roughly six months to evaluate data and proposed mitigation steps; that compressed window could pressure both reviewers and the manufacturer to prioritize clear, reproducible evidence on immune response and safety in older adults.

For public health, an approved mRNA flu vaccine could expand tools for preventing influenza, especially among older populations who face higher hospitalization and mortality risks. The mRNA platform allows more rapid antigen updates compared with some traditional manufacturing methods, which could be advantageous for matching circulating strains in a given season.

At the same time, the political backdrop and recent reductions in mRNA-related funding create uncertainty for downstream uptake and future R&D investment. Industry sources report that cancellations and funding cuts worth hundreds of millions of dollars have altered plans for new mRNA projects, raising questions about manufacturing scale-up and global supply reliability.

Economically, a successful approval would position Moderna to enter the seasonal influenza market, competing with manufacturers using egg-based, cell-based, and recombinant technologies. Market entry by an mRNA vaccine maker could accelerate innovation but also trigger pricing, procurement, and distribution debates among payers and public health agencies.

Comparison & Data

This condensed table compares Moderna’s filing strategy with typical seasonal vaccine pathways. The accelerated approval route for older adults depends on surrogate endpoints and commitments to confirmatory post-market studies, which can affect timelines and coverage decisions.

Reactions & Quotes

Moderna said regulators agreed to accept the company’s application for review after additional discussions between the parties.

Moderna (company statement)

The FDA had previously described aspects of the study design as not meeting its standards, prompting the initial refusal and subsequent follow-up talks.

U.S. Food and Drug Administration (regulatory statement)

Public health experts note that mRNA platforms proved their utility during the COVID-19 pandemic and are generally considered safe by the scientific community, though data and surveillance are essential for each new use.

Public health scientists (collective assessment)

Unconfirmed

• Specific technical changes Moderna proposed to address the FDA’s design concerns are not publicly detailed.
• Exact start date and sample size for the promised post-market study in the 65+ cohort have not been disclosed.
• Whether distribution agreements or procurement commitments outside the U.S. are in place if the vaccine is authorized remains unclear.

Bottom Line

The FDA’s decision to accept Moderna’s application for review marks an important regulatory development for mRNA use beyond COVID-19 and sets a clear August 2026 timetable for a determination. The split application strategy — standard approval for ages 50–64 and accelerated approval for 65+ with a post-market commitment — is designed to balance earlier access for higher-risk adults with additional evidence gathering.

Outcomes of this review will influence not only seasonal influenza prevention options for older adults but also investor and industry confidence in mRNA vaccine development amid shifting federal policy and funding. Close attention to the FDA’s evaluation of trial endpoints and the details of the post-market study will be essential for assessing the vaccine’s clinical and public health value.

Sources

• The New York Times (news)