FDA refuses to review Moderna's mRNA flu vaccine
arstechnica.com

... The Food and Drug Administration has refused to review Moderna's application for an mRNA flu vaccine, the company revealed Tuesday.

While the move came as a surprise to the high-profile vaccine maker, it is just the latest hostility toward vaccines"and mRNA vaccines in particular"from an agency overseen by the fervent anti-vaccine activist Robert F. Kennedy Jr. In his first year in office, Kennedy has already dramatically slashed childhood vaccine recommendations and canceled $500 million in research funding for mRNA vaccines against potential pandemic threats.

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. ...