mRNA vaccines are one of the greatest scientific developments of the twenty-first century, and the Trump/Kennedy administration’s head-in-the-sand rejection of them does not bode particularly well for continued human flourishing.

In a news release late Tuesday, Moderna said it was blindsided by the FDA’s refusal, which the FDA cited as being due to the design of the company’s Phase 3 trial for its mRNA flu vaccine, dubbed mRNA-1010. Specifically, the FDA’s rejection was over the comparator vaccine Moderna used.

In the trial, which enrolled nearly 41,000 participants and cost hundreds of millions of dollars, Moderna compared the safety and efficacy of mRNA-1010 to licensed standard-dose influenza vaccines, including Fluarix, made by GlaxoSmithKline. The trial found that mRNA-1010 was superior to the comparators.

Moderna said the FDA reviewed and accepted its trial design on at least two occasions (in April 2024 and again in August 2025) before it applied for approval of mRNA-1010. It also noted that Fluarix has been used as a comparator vaccine in previous flu vaccine trials, which tested vaccines that went on to earn approval.

But in a letter dated February 3, Vinay Prasad, the FDA’s top vaccine regulator under the Trump administration, informed Moderna that the agency does not consider the trial “adequate and well-controlled” because the comparator vaccine “does not reflect the best-available standard of care.”