WASHINGTON (AP) 鈥� The U.S. Food and Drug Administration is refusing to consider Moderna鈥檚 application for a new flu vaccine made with Nobel Prize-winning mRNA technology, the company announced Tuesday.
The news is the latest sign of the FDA鈥檚 under Health Secretary Robert F. Kennedy Jr., particularly those , which he has criticized before and after becoming the nation鈥檚 top health official.
Moderna received what鈥檚 called a 鈥渞efusal-to-file鈥� letter from the FDA that objected to how it conducted a 40,000-person clinical trial comparing its new vaccine to one of the standard flu shots used today. That trial concluded the new vaccine was somewhat more effective in adults 50 and older than that standard shot.
The letter from FDA vaccine director Dr. Vinay Prasad said the agency doesn鈥檛 consider the application to contain an 鈥渁dequate and well-controlled trial鈥� because it didn鈥檛 compare the new shot to 鈥渢he best-available standard of care in the United States at the time of the study.鈥� Prasad鈥檚 letter pointed to some advice FDA officials gave Moderna in 2024, under the Biden administration, which Moderna didn鈥檛 follow.
According to Moderna, that feedback said it was acceptable to use the standard-dose flu shot the company had chosen 鈥� but that another brand specifically recommended for seniors would be preferred for anyone 65 and older in the study. Still, Moderna said, the FDA did agree to let the study proceed as originally planned.
The company said it also had shared with FDA additional data from a separate trial comparing the new vaccine against a licensed high-dose shot used for seniors.
The FDA 鈥渄id not identify any safety or efficacy concerns with our product鈥� and 鈥渄oes not further our shared goal of enhancing America鈥檚 leadership in developing innovative medicines,鈥� Moderna CEO Stephane Bancel said in a statement.
It鈥檚 rare that FDA refuses to file an application, particularly for a new vaccine, which requires companies and FDA staff to engage in months or years of discussions.
Moderna has requested an urgent meeting with FDA, and noted that it has applied for the vaccine鈥檚 approval in Europe, Canada and Australia.
In the last year, FDA officials working under Kennedy have rolled back recommendations around COVID-19 shots, added extra warnings to the two leading COVID vaccines 鈥� which are made with mRNA technology 鈥� and removed critics of the administration鈥檚 approach from an FDA advisory panel.
Kennedy announced last year that his department would cancel more than and funding for the development of vaccines using mRNA.
FDA for decades has allowed vaccine makers to quickly update their annual flu shots to target the latest strains by showing that they trigger an immune response in patients. That鈥檚 a far more efficient approach than running long-term studies tracking whether patients get the flu and how they fare. In an internal memo last year, Prasad wrote that the streamlined method would no longer be permitted 鈥� leading to pen an editorial condemning the statements.
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