FDA Declines Review Of Moderna mRNA Flu Vaccine
CBER director Vinay Prasad signed a letter saying Moderna’s Phase 3 submission lacked a high‑dose comparator for those 65+, prompting the FDA to decline filing the application.
Overview
The FDA declined to file or review Moderna’s application for its mRNA influenza vaccine after CBER director Vinay Prasad signed a letter saying the submission was not sufficiently complete to enable a substantive review.
The agency said the issue was that the Phase 3 trial did not use the CDC‑recommended high‑dose comparator for participants aged 65 and over, citing 2024 guidance, while Moderna says the design was discussed with CBER.
Moderna said it included standard‑ and high‑dose comparators and posted communications showing prior discussions with the agency, and FDA spokesperson Andrew Nixon said Moderna refused to follow clear 2024 guidance and exposed 65+ participants to risk.
The Phase 3 study enrolled roughly 40,000 to nearly 41,000 adults aged 50 and older, and the decision comes amid policy changes under HHS Secretary Robert F. Kennedy Jr., including cancellation of a $590 million contract with Moderna.
FDA officials said Moderna could revise its application or focus on the 50–64 age cohort, and Moderna said its mRNA flu vaccine is being reviewed in Europe, Canada and Australia and may be submitted elsewhere this year.
Analysis
Center-leaning sources frame the story as an internal-agency showdown, portraying Prasad as overruling career scientists and acting politically rather than on science. They foreground terms like "single-handedly" and "political appointee known for causing turmoil," rely on unnamed FDA sources and a cited memo, and highlight meetings to emphasize conflict.
Sources (5)
FAQ
The FDA declined because the Phase 3 trial lacked a high-dose comparator for participants aged 65 and older, as required by 2024 guidance, deeming the application incomplete for substantive review.
History
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