Moderna's mRNA flu shot earns FDA approval after rollercoaster review

Remaining uncertainty

At the FDA advisory committee’s June meeting, experts expressed optimism about an mRNA-based flu vaccine. The platform—the same used in the company’s COVID-19 vaccines—is agile, easily allowing tweaks and updates to vaccine design, and it offers swifter vaccine production at scale compared to existing flu vaccines. Traditional flu vaccines are grown in fertilized chicken eggs, a process that requires six to eight months, compared to mRNA vaccines’ one to two months.

Moderna CEO Stéphane Bancel celebrated the approval in a statement Thursday, saying it “demonstrates the continued strength and versatility of our mRNA platform.”

“Flu remains a significant public health challenge, and mFLUSIVA provides an important new option for America’s seniors,” he said. “This approval also reflects the ongoing potential of our mRNA platform to help address important public health challenges through continued scientific innovation.”

Despite the approval, the vaccine still faces some uncertainty. The CDC advisory panel that makes recommendations for federal vaccine policy is effectively defunct. In March, a federal judge ruled that most of the anti-vaccine allies Kennedy had installed onto the advisory panel were unqualified. The judge thus ordered a temporary injunction reversing their appointments and undoing many of Kennedy’s changes to federal vaccine recommendations. The Trump administration is currently appealing the judge’s ruling. But amid the litigation, the CDC’s panel—the Advisory Committee on Immunization Practices—has not met.

Without an ACIP recommendation on mFLUSIVA’s clinical use for the quickly approaching flu season, doctors will face uncertainty about which adults over age 50 should be recommended to use the vaccine. It’s also unclear if mFLUSIVA will be covered by federal vaccine programs or private insurance companies, which are required to cover ACIP-recommended vaccines.

Moderna said it expects to have mFLUSIVA available for the 2026–2027 flu season. But The Wall Street Journal reported that Wall Street is not expecting meaningful sales until the 2027–2028 season.