FDA approves first mRNA vaccine for seasonal flu

The U.S. Food and Drug Administration (FDA) has approved an innovative new seasonal flu vaccine that utilizes mRNA technology. Developed by Moderna, the vaccine, called mFlusiva or mRNA-1010, has received FDA approval for individuals aged 50 and above. Similar to the mRNA-based COVID-19 vaccine, mFlusiva uses mRNA to instruct human cells to produce hemagglutinin (HA), a protein present on the surface of influenza viruses.

This protein is the primary target of traditional flu vaccines, and the immune system learns to recognize it upon vaccination, enhancing its ability to prevent infections.

The approval of mFlusiva is based on a recent, large-scale clinical trial involving over 40,000 participants aged 50 and older. Half of the participants received the mRNA vaccine, while the other half received a standard dose of a conventional flu vaccine. The results showed that the mRNA vaccine provided 26.6% better protection against flu illness compared to the conventional vaccine.

Moreover, the mRNA vaccine demonstrated superior protection against all three flu subtypes included in the vaccine formulation. In individuals aged 65 and above, the vaccine's protective efficacy was even higher at 27.4%.

Although the mRNA vaccine had a higher incidence of mild side effects, such as injection-site pain, headache, fatigue, and muscle aches, these reactions were generally short-lived and not severe. An additional trial comparing mFlusiva to an existing high-dose flu vaccine for adults aged 65 and older revealed that the mRNA vaccine generated greater immune protection, as indicated by antibody levels.

With this approval, the FDA's decision marks a notable shift in the government's stance on mRNA vaccines. Under the previous administration, significant federal funding for mRNA vaccine research and development was reduced, and opposition to mRNA technology was evident. However, Moderna CEO Stéphane Bancel expressed optimism about the approval, stating that mFlusiva offers an essential new option for seniors in the United States.

The vaccine has received standard approval for ages 50 to 64 and accelerated approval for those 65 and older, with further trials planned to confirm its superiority over the high-dose vaccine in this age group.