FDA Approves First mRNA Flu Vaccine for Adults 50 and Older

The FDA approved mFlusiva, Moderna's mRNA-based influenza vaccine, for adults aged 50 and older in early August 2026. It is the first mRNA vaccine authorized for seasonal influenza.

The agency granted traditional approval for adults aged 50 to 64 and accelerated approval for those 65 and older. Moderna must conduct additional post-market studies to confirm clinical benefits for the older age group.

A Phase 3 trial involving more than 40,000 participants showed mFlusiva was approximately 26 to 27 percent more effective than standard-dose flu shots. Data also indicated the vaccine cut hospitalizations by roughly half compared to standard vaccines.

mRNA technology allows manufacturers to produce the vaccine in two to three months from strain selection to rollout, compared to the six months required for traditional egg-based flu vaccines. That faster timeline allows for a closer match to circulating influenza strains.

Despite the approval, distribution for the 2026-2027 flu season faces complications. A federal judge has blocked the CDC's Advisory Committee on Immunization Practices from convening, which is typically required for widespread insurance coverage and inclusion in federal programs like Medicaid.

Moderna funded its own clinical trials independently of federal support. The Department of Health and Human Services had previously reduced funding for mRNA vaccine research, but that did not affect this program.