Moderna said its updated mRNA influenza vaccine reduced flu infections by 94% in a late-stage trial involving about 42,000 participants. The company disclosed the results in a release reported by Reuters, calling the findings a major step toward a newer seasonal flu shot designed to better match circulating strains.

According to the company, the trial compared the updated vaccine with standard flu shots and found that side effects were similar to those seen with existing vaccines. The study data have not yet been fully reviewed in an independent journal, so the results should still be viewed as preliminary until regulators and outside experts have a chance to assess them.

If confirmed, the findings could strengthen the case for mRNA-based flu vaccines as a faster way to respond to changing influenza variants. Seasonal flu vaccines are updated regularly, but their effectiveness can vary year to year depending on how closely the shot matches the strains in circulation.

Moderna’s report adds to growing interest in next-generation vaccine platforms after the rapid rollout of mRNA technology during the COVID-19 pandemic. The company has not yet said when it expects to seek broader regulatory review or potential approval for the updated flu shot.