The Food and Drug Administration on Monday cleared updated COVID-19 booster shots from Pfizer and Moderna for use in people as young as 6 months old, paving the way for fall and winter vaccination campaigns.
The updated vaccines are designed to better protect against circulating coronavirus strains by targeting a subtype of the omicron variant known scientifically as XBB.1.5. They’re also monovalent, or designed around a single strain, rather than the bivalent shots that were rolled out last year.
An advisory committee of the Centers for Disease Control and Prevention is set to meet Tuesday to give formal recommendations for the reformulated shots’ use. Pfizer and Moderna expect supplies of their respective shots will be available at pharmacies and other healthcare settings in the coming days.
The companies redesigned their messenger RNA-based vaccines in line with FDA guidance for the 2023-2024 season. Agency advisers in June endorsed updating the shots to target the XBB strain, which was then the dominant version of the virus. Immune response data from clinical and preclinical trials showed the shots produce antibodies against that variant, as well as more recently mutated types like BA.2.86, and those known as Eris and Formax.
The FDA’s decision comes as COVID cases have risen in the U.S., bringing both hospitalizations and deaths higher.
“Vaccination remains critical to public health and continued protection against serious consequences of COVID-19, including hospitalization and death,” said Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, in a statement.
The FDA cleared a single dose of either Pfizer’s or Moderna’s new shots for anyone over 5 years old, regardless of prior vaccination status, provided they are at least two months removed from their last COVID vaccine dose.
Vaccinated infants over 6 months and children through 4 years old can receive one or two doses, depending on prior vaccination, while those in that age range who haven’t been vaccinated yet are eligible for either two or three doses.
Moving forward, the agency envisions annual updates for COVID vaccines, similar to those for influenza. This fall, older adults will also have the choice to receive one of two recently approved vaccines for respiratory synctial virus, or RSV.
The newly approved COVID vaccines are largely not being bought in bulk by the federal government, as past iterations were. But the updated shots will be covered by private insurance and Medicare, and the Biden administration has launched the “Bridge Access Program” for people who are uninsured.
The FDA has not yet approved an updated protein-based shot from drugmaker Novavax, which previously lost out to Pfizer and Moderna on the market despite winning approval for its COVID vaccine. The agency is still reviewing the Maryland-based biotechnology company’s application for people aged 12 years or older.