FDA approves updated COVID-19 vaccines from Moderna, Pfizer/BioNTech

The FDA has approved the updated COVID-19 vaccines Comirnaty, developed by Pfizer and BioNTech, and Spikevax, from Moderna. These vaccines are designed to offer enhanced protection against the Omicron KP.2 strain of the virus. The approval covers mRNA vaccines for individuals aged 12 and older, while emergency-use authorization has been granted for pediatric dosing schedules for children aged 6 months to 11 years.

Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, emphasized that these updated vaccines meet rigorous scientific standards for safety, effectiveness, and manufacturing quality. Marks highlighted the necessity of these retooled vaccines due to the waning immunity observed in the population from previous virus exposure and prior vaccinations.

This regulatory clearance signifies a shift in strategy by US health officials in combating COVID-19. Moving forward, the FDA anticipates that COVID-19 vaccines will need to be evaluated annually, akin to seasonal flu vaccines. This aligns with recent efforts by drugmakers to develop a combined COVID-19/flu vaccine.

Both Pfizer-BioNTech and Moderna are in the late stages of testing their respective combination vaccines. Moderna’s candidate, known as mRNA-1083, appears to have made significant progress. The vaccine includes components from the seasonal flu candidate mRNA-1010 and a next-generation COVID-19 shot. In a Phase III study conducted in June, Moderna's combination vaccine met the primary endpoints, showing a higher immune response compared to the comparator shots used in the trial.

In contrast, Pfizer and BioNTech's combination vaccine, which pairs Comirnaty with a trivalent flu vaccine, yielded mixed results in a Phase III study. While the combination jab was comparable to Comirnaty in generating a COVID-19 immune response, it showed only a trend of stronger responses against influenza A compared to the licensed flu shot. However, it appeared less effective against the influenza B strain.

This evolving vaccine strategy aims to provide more robust and comprehensive protection against both COVID-19 and seasonal flu, addressing the ongoing challenges posed by virus mutations and waning immunity.