FDA Reverses Decision, Will Review Moderna's mRNA Flu Vaccine Application
The FDA has reversed its earlier refusal and will now review Moderna's mRNA-based flu vaccine application, with a decision expected by August 5. The company modified its regulatory approach to address concerns about older adults.
In a sudden reversal, the U.S. Food and Drug Administration has agreed to review Moderna's experimental mRNA influenza vaccine. The move comes just one week after the agency refused to evaluate the company's application, a decision that sent shockwaves through the biotech industry.
The initial rejection centered on the design of Moderna's clinical trials. Regulators had previously argued that the company should have tested its shot against a higher-strength flu vaccine for the older adults in the trial's control group. The FDA sent a "refusal to file" letter on Feb. 3 calling the application "inadequate for review." Such letters are rare, according to a 2021 study in JAMA Internal Medicine.
Following a Type A meeting, the FDA has assigned a Prescription Drug User Fee Act (PDUFA) goal date of August 5 for mRNA-1010, which is aimed at adults aged 50 and older. Under the newly accepted application, Moderna is seeking two types of approval based on age. The company is asking for full approval for adults aged 50 to 64. For those aged 65 and older, it is seeking "accelerated approval," which allows a product to reach the market faster based on early data while more research continues.
To address the FDA's previous concerns about older people, Moderna has committed to performing a post-marketing study. This means they will continue to collect data on how well the vaccine protects seniors after it is already being used by the public.
If approved, this would be the first flu vaccine to use the same messenger RNA technology that powered Moderna's COVID-19 shots. While traditional flu vaccines inject a virus protein into the body to stimulate the immune system, mRNA vaccines supply cells with the code to make the virus protein that then stimulates the immune system.
To test the safety and effectiveness of its mRNA flu shot, Moderna conducted two phase 3 trials. In one trial, more than 40,000 participants got the experimental shot or a standard flu shot. Another trial compared the mRNA vaccine to a standard shot and the high-dose shot recommended for seniors. The Massachusetts-based company said it had compared the vaccine with Fluarix, an approved standard-dose flu shot.
The FDA's acceptance of the biologics license application marks a significant step for Moderna, as mRNA-1010 has now been accepted for review in multiple regions, including the U.S., Europe, Canada, and Australia. The company plans further submissions in 2026, with expectations for potential approvals in the same year, subject to regulatory reviews.
The CEO expressed optimism about the upcoming flu season. "Pending FDA approval, we look forward to making our flu vaccine available later this year so that America's seniors have access to a new option to protect themselves against flu," the CEO said in a statement. This timeline would allow the company to distribute the shots in time for the fall respiratory virus season.
Moderna reported a fourth-quarter loss of $2.11, beating the expected loss of $2.59, lower than a loss of $2.91 a year ago. The company reported quarterly sales of $678 million, topping the expected $626.097 million. Moderna is targeting up to 10% revenue growth from $1.94 billion in 2025 and expects the 2026 revenue split to be approximately 50% U.S. and approximately 50% international.
Since taking office, the Health Secretary, a longtime vaccine skeptic, has canceled roughly $500 million in federal grants and contracts for mRNA-related projects. In May, the U.S. Department of Health and Human Services pulled funds for Moderna to develop a bird flu vaccine. In August, HHS announced plans to wind down $500 million in mRNA projects.
The Department of Health and Human Services confirmed Moderna's announcement but did not comment on past positions. "Discussions with the company led to a revised regulatory approach and an amended application, which FDA accepted," said a spokesperson for HHS. "FDA will maintain its high standards during review and potential licensure stages as it does with all products."