The US Food and Drug Administration (FDA) has refused to consider Moderna's application for a new mRNA-based flu vaccine. A senior FDA official called Moderna's clinical trial a “brazen failure” due to the study design. The control group for people over 65 received a standard flu shot instead of the recommended high-dose vaccine. This led the FDA to declare the trial “not adequate and well controlled.” Experts dispute the FDA's decision. Richard Hughes IV said, “It’s all pretext and obfuscation when the real agenda is rejecting conventional science and serving a predetermined anti-vaccine agenda.” Dorit Reiss added, “Personally humiliating a company is not a legitimate reason to refuse to review a submission.” An anonymous FDA official warned Moderna, “We told you not to run it in over 65. You didn’t do what we told you, so go back to the drawing board.” Moderna stated the FDA had approved the trial design and only recently raised concerns. Chris Ridley, Moderna’s spokesperson, said, “This was an FDA-approved trial design.” The FDA's letter, signed by Vinay Prasad, said the control group lacked “the best-available standard of care.” Prasad’s role is controversial and has faced allegations of misconduct. Moderna may revise the trial to focus on participants aged 50 to 64. The FDA said the added data on older participants was not strong enough to approve the vaccine. Andrew Nixon from the US Department of Health and Human Services called concerns about bias against mRNA vaccines “baseless.” Still, virologist Angela Rasmussen said, “They’re just coming up with reasons to not approve mRNA anything.” Experts warn this move could harm vaccine research and public health. Rasmussen said, “An mRNA flu vaccine is hugely important for public health,” especially for those with egg allergies. The FDA’s rejection of Moderna's vaccine application sends a strong message to developers and could chill future vaccine innovation in the US.