U.S. — The Food and Drug Administration faces a Wednesday deadline to make a decision on Moderna's mRNA-based flu shot. If approved, the Moderna vaccine would be the first mRNA-based flu shot to reach the market.

The regulatory review follows a reversal by the agency after it initially refused to consider the application in February 2025. In June, a panel of advisers to the FDA recommended that the agency approve the vaccine.

Moderna president Stephen Hoge received a letter from the FDA in February stating the agency would not review the application. The rejection arrived despite prior communications between the company and regulators regarding the submission process.

"We had talked to the FDA at every step along the way, including prior to filing," Hoge said. "And they had said, you can go forward and submit and we will conduct a review."

Hoge described the moment his team learned of the agency's change in position. "Charbel came up to me and just had a very nervous look on his face," he said. "That's where you pop it up on a screen and it hits you, you know, right in the face."

A little over a week after the initial rejection, the FDA agreed to review the vaccine after Moderna promised to add a confirmatory study if the vaccine reaches the market. The agency's shift occurred as Health and Human Services Secretary Robert F. Kennedy Jr. exerted influence over federal health policy.

Kennedy is the incumbent United States secretary of health and human services, having held the position since February 13, 2025. The FDA's reversal on reviewing the application followed pressure from HHS, as evidenced by a leaked email showing Kennedy's communications director instructed the CDC to halt vaccine promotion campaigns.

Kennedy's office instructed the CDC to halt flu vaccine promotion during a 2025 outbreak, as revealed by leaked emails. This action reflected a pattern of prioritizing his personal vaccine skepticism over public health messaging.

In May 2025, the HHS revoked a $600 million contract with Moderna to develop a bird flu vaccine, citing failure to meet scientific standards. This marked a prior instance of Kennedy's administration terminating mRNA-related projects.

The FDA independently selected influenza vaccine strains for the 2025-2026 season without relying on its traditional advisory committee. This shift in process occurred in July 2025 under Kennedy's tenure.

PureSource News previously reported that Kennedy developed guidance for antidepressant discontinuation. An HHS spokesman addressed the agency's approach to the current review.

"Under Secretary Kennedy's leadership, HHS is advancing President Trump's commitment to strengthen public health through gold-standard science, and FDA will continue applying rigorous, evidence-based standards to every product it reviews while supporting innovation that meets those standards," the spokesman said.

Moderna is holding off on some planned mRNA research pending the FDA's decision. Jeff Coller is a professor at Johns Hopkins University who has studied mRNA technology for decades. Rena Conti is a health economist at Boston University.

The outcome of this review will determine whether mRNA technology expands beyond COVID-19 vaccines into seasonal influenza prevention. The process has unfolded during significant administrative changes, including the revocation of a major federal contract with Moderna earlier in 2025.

The FDA's decision comes after the agency altered its standard procedure for selecting vaccine strains by bypassing its traditional advisory committee. The department has stated it will apply rigorous standards while supporting innovation, even as it has previously terminated mRNA projects cited for failing to meet scientific benchmarks.

Why It Matters

The FDA's decision determines whether mRNA technology expands beyond COVID-19 vaccines into seasonal influenza prevention. This review occurs after the agency reversed an initial refusal to consider the application, a shift that followed pressure from Health Secretary Robert F. Kennedy Jr., who has questioned the value of mRNA vaccine technology. The outcome will influence Moderna's planned research efforts and set a precedent for how federal regulators evaluate next-generation vaccine platforms under current leadership.