FDA approves updated mRNA vaccines for COVID-19

Moderna Therapeutics and Pfizer have received approval for an updated vaccine formula of their messenger RNA (mRNA) vaccines against the SARS-CoV-2 virus. The new vaccine formulas for the 2024-2025 fall and winter season will offer protection against the Omicron variant KP.2 strain of the virus, which is currently in circulation.

In the announcement, the FDA stated that the goal of this emergency approval is to “more closely target currently circulating variants and provide better protection against serious consequences of COVID-19, including hospitalization and death.”

The FDA initially advised the mRNA vaccine manufacturers, back in June, that their formula for the 2024-2025 COVID-19 vaccines should target the highly contagious JN.1 variant, which started circulating at the end of last year. As the SARS-CoV-2 virus has continued to evolve and the number of cases increased, the FDA determined that the preferred target for the vaccines should be the KP.2 strain, which descends from the JN.1 variant.

“Vaccination continues to be the cornerstone of COVID-19 prevention,” said Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research. “These updated vaccines meet the agency’s rigorous, scientific standards for safety, effectiveness, and manufacturing quality.”

The updated mRNA COVID-19 vaccines include Pfizer and BioNTech’s Comirnaty and Moderna Therapeutics’ Spikevax, which are approved in the US for individuals who are 12 years of age and older, as well as their counterparts for children from 6 months to 11 years of age.

“This approval is timely, as COVID-19 remains a significant health risk and is the leading cause of respiratory illness-related hospitalization, regardless of age or health condition,” stated Moderna in a press release.

The emergency use authorization (EUA) of the updated vaccines was based on manufacturing and nonclinical data to support the change to the new formulas. The updated vaccines will be manufactured using a similar process as previous formulas of the vaccines, which have been administered to hundreds of millions of people in the US.

A key advantage of mRNA technology is that the manufacturing time is significantly shorter compared to traditional vaccine technologies. Novavax, which produces a protein-based COVID-19 vaccine approved in the US, previously stated that it will not be able to make a vaccine against the KP.2 strain in time for the fall, and will instead distribute a vaccine targeting the JN.1 strain.

The FDA stated that it will keep reviewing any additional applications for COVID-19 vaccines on an ongoing basis. The regulatory agency is anticipating that, going forward, the composition of COVID-19 vaccines will need to be assessed annually, similarly to how seasonal influenza vaccines are updated every year.