After getting slapped with a surprise refuse-to-file letter signed by former CBER Director Vinay Prasad, Moderna’s flu vaccine application will now go before the FDA’s Vaccine advisory committee.
The FDA will convene its Vaccines and Related Biological Products Advisory Committee next month to assess Moderna’s investigational mRNA flu vaccine, which in February was the center of controversy after the agency initially refused to accept the application for review.
The adcomm meeting—only the second in the past 10 months, following one for AstraZeneca’s cancer drugs last month, will take place on June 18, according to a Federal Register notice posted Friday. The vaccine panel, which typically consists of independent outside experts, will discuss the safety and efficacy of Moderna’s MFLUSIVA for the prevention of flu in patients 50 years and up, as caused by the influenza virus subtypes A and B.
It isn’t yet clear what the specific points of discussion will be during the adcomm as the FDA hasn’t released its briefing documents yet. As of writing, the meeting is also not yet listed on the agency’s calendar.
In early February, the FDA slapped Moderna’s flu application with a refusal-to-file letter, declining to accept the submission for review. The letter, which was signed by former Center for Biologics Evaluation and Research Director Vinay Prasad, contended that Moderna’s pivotal trial for the vaccine used a control group that “does not reflect the best-available standard of care.”
“The FDA rejected Moderna’s application for filing because the company refused to follow very clear FDA guidance from 2024 to test its product in a clinical trial against a CDC-recommended flu vaccine to compare safety and efficacy,” spokesperson Andrew Nixon said shortly after the agency turned down Moderna’s application.
This rebuff drew strong blowback from the industry—so much so that the Department of Health and Human Services had to publicly defend Prasad and then–FDA Commissioner Marty Makary was called into President Donald Trump’s office to hear his “frustration” over the agency’s handling of vaccine issues more broadly, Politico reported at the time.
Moderna and the FDA have since arrived at a compromise, with the regulator agreeing to accept the application for review. The amended application is seeking regular approval for use in adults 50 to 64 years and accelerated approval for those 65 years and up. A decision is expected in August.
Shortly after, an investigation was launched into Prasad’s professional conduct, with accusations flying that he berated his staff and retaliated against reviewers who questioned his decisions. A few weeks later, Makary announced that Prasad would be leaving the FDA on April 30.
A series of high-level reassignments and resignations at the FDA have followed his departure, including that of Makary himself, plus Prasad ally and Acting CBER Director Katherine Szarama, Center for Drug Evaluation and Research (CDER) Acting Director Tracy Beth Høeg, and the agency’s chief of staff and chief AI officer. The turnover at the top of CBER and CDER brings the total number of people who have run those two review units since Trump took office to six each.
