FDA Approves First mRNA Flu Vaccine for Adults 50+, Backed by 27% Higher Efficacy
Updated
Updated · CNN International · Aug 14
FDA Approves First mRNA Flu Vaccine for Adults 50+, Backed by 27% Higher Efficacy
3 articles · Updated · CNN International · Aug 14
Summary
Moderna’s mFlusiva is set for a fall launch after FDA approval for adults 50 and older, marking the first US flu shot built on mRNA technology.
A 40,000-plus-person study found the vaccine was about 27% more effective than standard flu shots in the 2024-25 season, while mostly causing mild-to-moderate short-term reactions.
Adults 50 to 64 received standard approval, but those 65 and older got accelerated approval because Moderna’s original trial used a standard-dose comparator instead of an enhanced vaccine recommended for seniors.
Moderna must now run a post-marketing study this flu season to show the stronger antibody response in older adults translates into better real-world protection against illness.
Rollout could be limited this season because pharmacies ordered flu stock earlier in the year, and insurance coverage remains unclear until CDC vaccine advisers meet again after months of disruption.