US health advisers are debating a new type of flu vaccine on Thursday, the first made with the same mRNA technology that was key to ending the Covid-19 pandemic. Moderna is seeking Food and Drug Administration (FDA) approval of its new shot, dubbed mFlusiva, as an option for people aged 50 and older. The FDA advisory committee meeting is a step toward a final decision ahead of the winter flu season.
Study Shows 27% Reduction in Flu Cases
In a study of 40,000 people aged 50 and older, Moderna's mRNA vaccine reduced flu cases by about 27% compared to those given another routinely used vaccine brand. Tens of thousands of Americans die from influenza every year, and older adults are among the most vulnerable. There are various types of flu vaccines already available in the US, including three specifically recommended for people aged 65 and older. However, vaccines made with the Nobel Prize-winning mRNA technology are faster to manufacture than other types – something experts say might help if the shape-shifting flu virus mutates in a way that requires suddenly brewing new doses to match.
FDA Review and Safety Concerns
Ahead of the meeting, the FDA published a favorable review of that data and reported no safety concerns. Moderna is seeking full approval for the vaccine's use in the 50- to 64-year-old population, along with authorization for use in those aged 65 and older while it conducts additional testing.
Public Dispute Over Study Design
Earlier this year, Moderna's data was at the center of a highly unusual public dispute as a then-top FDA official blocked the company's application for its first-of-its-kind shot. The embattled vaccine chief at the time, Dr Vinay Prasad, said the company should have compared its shot to a high-dose flu vaccine recommended for seniors rather than a standard-dose brand. It was a sign of the FDA's heightened vaccine scrutiny under Health Secretary Robert F Kennedy Jr.
Moderna challenged that decision, noting that FDA staff had approved that main study's design and citing a separate, smaller study comparing the mRNA shot with a high-dose vaccine for seniors. Days after the spat, the FDA accepted Moderna's application.
Additional Data from Smaller Study
The expert panel also will assess that smaller study, which found Moderna's shot generated flu-fighting antibodies similarly to a high-dose senior shot. The FDA's initial review noted the new vaccine lacks data on very frail older adults and those with weak immune systems.
