FDA staff see potential for Moderna flu shot in older adults

Staff at the U.S. Food and Drug Administration have indicated that data for Moderna's flu vaccine, mFlusiva, shows a strong immune response that may support its effectiveness in adults aged 65 and older. The briefing documents, published ahead of an advisory committee meeting on June 18, also noted superior relative vaccine efficacy in adults aged 50 to 64 compared to standard-dose flu vaccines.

Moderna's shares saw a 2% increase following the news. Analyst Andrew Tsai of Jefferies anticipates significant sales for Moderna's flu and COVID-flu combination vaccines by 2030.

However, FDA staff highlighted that the application for the 65 and older age group primarily relies on immunogenicity data, not the CDC-preferred high-dose vaccines for this demographic. They also pointed to limited one-season data and a higher incidence of short-term side effects, recommending postmarket studies.

Despite these concerns, former FDA chief scientist Jesse Goodman stated the assessment appeared reasonable and supported approval for both age groups. Moderna is seeking traditional approval for adults aged 50 to 64 and accelerated approval for those 65 and older. The FDA had previously rejected the application in February, citing concerns about the control arm's vaccine choice, but later accepted an amended application after Moderna agreed to conduct a post-approval study.

If approved, mFlusiva would mark the first mRNA-based seasonal flu vaccine in the U.S., with a regulatory decision anticipated by August 5.