The U.S. Food and Drug Administration (FDA) has agreed to review Moderna’s mRNA-based influenza vaccine, reversing its previous refusal to consider the application. The decision follows a meeting between Moderna and the FDA after the company received a Refusal-to-File (RTF) letter on February 10.
The amended regulatory pathway will allow Moderna to seek full approval of its mRNA-1010 flu shot for adults aged 50 to 64 years and accelerated approval for those aged 65 and older. The FDA’s initial concerns centered on the adequacy of clinical trials, particularly regarding older adults. The agency had previously recommended that Moderna use a high-dose vaccine as a comparator in studies involving seniors, in line with guidance from the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP).
“Moderna exposed participants age 65 and over to increased risk of severe illness by giving them a substandard of care against the recommendation of FDA scientists,” said Department of Health and Human Services spokesperson Andrew Nixon during a press call last Wednesday, according to Scientific American. “The most protective flu shots for seniors are a subset of high-dose flu shots recommended by the [ACIP], which would have served as the proper control in this study.”
Despite these issues, Moderna submitted data on a high-dose vaccine tested in adults aged 65 and older at the FDA’s request in August 2025. Following further discussions, the FDA has now accepted Moderna’s amended biologics license application (BLA) for review, setting an action date of August 5.
“We appreciate the FDA’s engagement in a constructive Type A meeting and its agreement to advance our application for review,” said Stéphane Bancel, CEO of Moderna.
Moderna’s share price rose more than 8.5% following news of the agreement.
This development comes amid what experts describe as a challenging flu season due to mismatches between circulating strains and current vaccines. Stephen Hoge, president and head of research at Moderna, noted during an earnings call that faster production processes enabled by mRNA technology could help address such mismatches: “We do think this year in particular, where there’s a potential for a mismatch in one of the strains, it’s particularly important that technologies like Moderna’s mRNA platform are used to advance new and potentially improved products.”
The earlier RTF letter had cast doubt on whether Moderna could reach its goal of breaking even by 2028. Analysts at William Blair adjusted their forecasts following news of the setback but expect mRNA-1010—and eventually a combination flu/COVID vaccine—to generate significant revenue if approved.
Financial analysts from Jefferies observed that by 2027 or 2028, Moderna could have seven or more products launched across respiratory illnesses, oncology, and rare diseases. They also noted that continued cost reductions might enable Moderna to meet its cash breakeven target by 2028.
The rapid resolution recalls similar events last summer when Sarepta Therapeutics faced regulatory challenges with its Duchenne muscular dystrophy gene therapy but saw those restrictions lifted within days after additional dialogue with regulators.
