An mRNA-based seasonal flu vaccine from Moderna was 27 percent more effective at preventing influenza infections than a standard flu shot, the company announced this week.

The new results helped boost Moderna’s stock by more than 4% in early trading Monday, though the company’s shares are still down about 32% for the year. Moderna has more on the science behind mRNA. Copyright © 2025 HealthDay. All rights reserved.

Moderna said on Monday its experimental influenza vaccine was found to be 26.6% more effective than a currently approved annual flu shot when tested in adults aged 50 years and older in a late-stage study.