After the FDA’s decision to reject a review of Moderna’s mRNA-1010 flu shot, executives explain what Americans will miss out on as other nations embrace the technology.
The rest of the world may get access to Moderna’s pair of influenza vaccines before the U.S. does after the FDA declined to even review the application for mRNA-1010, executives warned. This comes as the U.S. is facing a brutal flu season due to a mismatch in circulating strains as compared to the existing shots. That’s a problem Moderna says it could have fixed with its technology.
“We absolutely feel that American seniors should have access to the same innovations,” President Stephen Hoge, who heads the biotech’s R&D operations, said during a fourth quarter earnings call on Friday. “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.”
Instead, Moderna is awaiting regulatory decisions in Canada, Europe and Australia for the singular flu shot mRNA-1010, with more applications to go. The shot could be offered in those regions as early as the 2027–2028 flu season.
Other countries could also now be first to see the company’s combination flu/COVID shot mRNA-1083. Moderna had been waiting for some advancement in the regulatory application for mRNA-1010 in the U.S. before submitting an approval request to the FDA for mRNA-1083. That shot now has an uncertain U.S. future following mRNA-1010’s refuse-to-file letter but meanwhile is progressing through regulatory bodies in other nations, Moderna noted on the earnings call.
Government officials in those countries are happy to see a new technology for routine annual vaccinations heading to the market, Hoge said, adding that European leaders in particular have been advocating for later strain selection for the flu in particular.
“As we’ve proceeded outside of the U.S., there has been strong appetite for the question of better strain matching,” he said.
The strains to be included in annual vaccines are typically decided months in advance by national health organizations, including the CDC in the U.S. and the World Health Organization globally, based on available data. Early research suggests that the flu shots that were distributed around the world for the 2025–2026 season were a mismatch with the strains that have actually been circulating.
Even the best scientists on the job can’t always be 100% spot on in identifying which strains might cause the most problems come flu season. The U.K. has reported about 32%–39% efficacy so far. The CDC has indeed been reporting an elevated flu season this year.
Moderna believes it can improve on the strain selection problem. mRNA technology—as demonstrated during the COVID-19 pandemic—can be manufactured quickly to react to viral mutations. More standard vaccines can take months to develop, meaning the strain selection has to happen much earlier to ensure product delivery in time for shot campaigns in the fall.
The U.S. has been a leader in terms of the COVID strain selection, choosing different viral strains than the rest of the world in two of the past four seasons, according to Hoge. “The data has shown that that better matching for the market has led to slightly better efficacy.”
Moderna actually ran a head-to-head clinical trial, “back in the bivalent days,” when the company’s shot Spikevax tackled just two strains, to test better matching strategies, Hoge pointed out. Efficacy was stronger with better matching.
Hoge foresees a future where flu vaccines can be tailored to different regions—which could have helped in this current season where the strain that is wreaking havoc on the U.S. is different from those circulating in the rest of the Northern Hemisphere.
“There are many other things we need to do to improve flu vaccines, but this is one we know we can do right now,” Hoge said.
With the FDA’s rejection of mRNA-1010, however, Americans will have a longer wait.
