In a surprising turn of events, officials from the Food and Drug Administration (FDA) informed Moderna in August that they would review the company’s application for a new influenza vaccine, reaffirming earlier guidance from previous leadership. However, recent developments have indicated a significant shift in the agency’s stance.
During a recent interview on the STAT podcast “The Readout LOUD,” Moderna’s president, Stephen Hoge, expressed confusion over the FDA’s sudden decision. Back in August, the agency had requested data from Moderna’s Phase 3 trial and seemed willing to consider the application, which led the company to believe it was on track for approval. Hoge noted that the FDA also sought additional analyses from previous studies conducted by Moderna, which the company included in its submission.
The unexpected “refusal-to-file” letter received by Moderna earlier this month left the company blindsided. Signed by Vinay Prasad, the head of the vaccine regulatory office, the letter cited concerns about the comparator arm used in Moderna’s trial, which was the standard flu vaccine. Reports indicate that there was internal readiness within the FDA’s vaccine office to proceed with the review, but Prasad apparently overruled that decision.
When asked if the FDA had communicated any changes in guidance regarding the comparator prior to the trial’s completion or the review process, Hoge clarified that no such changes had been conveyed. He emphasized the complexity and risks involved in developing new medicines, revealing that Moderna had invested close to a billion dollars in its Phase 3 study, ensuring that their approach was aligned with the FDA’s expectations over a five-year collaboration.
Hoge also addressed the broader implications of this sudden regulatory shift for both Moderna and the biopharmaceutical industry as a whole. He emphasized the challenges faced by companies in navigating regulatory pathways and the importance of consistent communication with agencies like the FDA.
This unexpected outcome raises questions about regulatory processes and the criteria used by the FDA in assessing new vaccines, particularly in light of the evolving landscape of public health and vaccine development.


