Moderna's New mRNA Flu Vaccine Rejected by FDA

Agency cites issues with clinical trial design in refusing to review application.

Published on Feb. 11, 2026

Got story updates? Submit your updates here. ›

The U.S. Food and Drug Administration has refused to consider Moderna's application for a new flu vaccine made with mRNA technology, the company announced. The FDA cited problems with how Moderna conducted a 40,000-person clinical trial comparing the new vaccine to a standard flu shot, saying it did not use the "best-available standard of care" as a comparator.

Why it matters

The decision highlights the heightened scrutiny the FDA is placing on vaccines, particularly those using mRNA technology, under the leadership of Health Secretary Robert F. Kennedy Jr. It also raises questions about the agency's willingness to accept streamlined approaches for updating annual flu shots that have been standard practice for decades.

The details

Moderna said the FDA issued a "refusal-to-file" letter objecting to how it conducted the clinical trial for the new mRNA-based flu vaccine. The agency said the trial did not compare the new shot to the "best-available standard of care" flu vaccine for adults 65 and older, as the FDA had previously advised the company. Moderna said it had shared additional data comparing the new vaccine to a licensed high-dose shot for seniors, but the FDA still declined to review the application.

  • In 2024, under the Biden administration, the FDA provided Moderna with feedback on the clinical trial design that the company did not follow.
  • On February 11, 2026, Moderna announced the FDA had refused to consider its application for the new mRNA flu vaccine.

The players

Moderna

A biotechnology company that develops vaccines and therapeutics, including the first authorized mRNA-based COVID-19 vaccine.

U.S. Food and Drug Administration (FDA)

The federal agency responsible for regulating and supervising the safety of food, drugs, medical devices, cosmetics, and other products in the United States.

Robert F. Kennedy Jr.

The current U.S. Secretary of Health, who has been critical of vaccines using mRNA technology in the past.

Dr. Vinay Prasad

The director of the FDA's vaccine division, who issued the "refusal-to-file" letter to Moderna.

Stephane Bancel

The CEO of Moderna.

Got photos? Submit your photos here. ›

What they’re saying

“The FDA '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,'”

— Stephane Bancel, CEO, Moderna (kpua.net)

What’s next

Moderna has requested an urgent meeting with the FDA to discuss the decision, and noted that it has applied for the vaccine's approval in Europe, Canada and Australia.

The takeaway

The FDA's rejection of Moderna's new mRNA flu vaccine application highlights the heightened scrutiny the agency is placing on innovative vaccine technologies under the leadership of Health Secretary Robert F. Kennedy Jr. This decision could have broader implications for the development and approval of other mRNA-based vaccines in the future.