# Moderna's MRNA.O mRNA-based seasonal flu vaccine worked better than conventional flu shots in a late-stage international trial.

*biotech · news · 2026-05-07 · USA TODAY*

## Key points

- Moderna's mRNA flu vaccine was 26.6% more effective than GSK's standard-dose shot in a large trial.
- The FDA reversed its initial rejection and now reviews Moderna's amended flu vaccine application.
- If approved, this shot would be the first U.S. mRNA-based seasonal flu vaccine.
- Moderna must conduct an additional study in adults 65+ as a condition of FDA review acceptance.
- Regulatory reviews for Moderna's flu shot are ongoing in the EU, Canada, and Australia.

**Companies:** Moderna, GSK
**Countries:** United States, Canada, Australia, Belgium

[Read the full story on USA TODAY](https://www.usatoday.com/story/life/health-wellness/2026/05/07/moderna-mrna-flu-vaccine-trial/89977953007/)

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