The FDA approved Moderna’s FDA mRNA flu vaccine on August 5 for people age 50 and older. The shot, called mFlusiva, uses the same technology as COVID-19 vaccines and moves toward select drug stores ahead of the upcoming flu season.
The decision rests on a study of 40,000 individuals who received either mFlusiva or a conventional flu shot. The mRNA group had 27 percent fewer cases, and Hanover Matz, a study coauthor at WashU Medicine in St. Louis, said people who received the mRNA-based vaccine had much higher antibody levels one month after vaccination.
Hanover Matz on production time
Matz said the mRNA approach can shorten manufacturing. “It can be produced much faster than the conventional flu vaccine, and this is very useful if the virus changes during the flu season.” He added, “With an mRNA-based vaccine, you could feasibly cut down that production time to a couple of months.”
That speed matters because conventional flu vaccines are typically generated in chicken eggs and are inactivated flu vaccines. The vaccine has to be prepared before fall, while the circulating strains are still being predicted. A June study published in Nature Immunology found that the mRNA vaccine generates a stronger and longer-lasting immune response than conventional flu vaccines.
mFlusiva and conventional flu shots
People who received the mRNA-based vaccine had much higher levels of antibodies against flu one month after vaccination, Matz said. “And those higher levels persisted for six months, which suggests that there is an increase in the duration of the protection.”
That sits against a practical problem for current seasonal flu-shot strategy. Conventional vaccines are anywhere from 40 percent to 60 percent effective at preventing infection, depending on the year, while influenza kills thousands of people in the United States each year and hospitalizes tens of thousands more.
FDA and select drug stores
The approval gives Moderna a new flu-shot platform for people age 50 and older ahead of the upcoming flu season. Moderna said mFlusiva will be available at select drug stores, which makes access the immediate issue for patients trying to plan their shots.
The part readers still need to watch is distribution, not the science. The FDA has cleared the vaccine for use, the clinical trial showed fewer cases in the mRNA group, and the question now is which drug stores will carry it and when it reaches them.
