Enlarge / The Food and Drug Administration headquarters in White Oak, Maryland. (credit: Getty | Congressional Quarterly)

The Food and Drug Administration greenlit two updated COVID-19 vaccine booster shots Monday—a day before advisors for the Centers for Disease Control and Prevention are scheduled to meet and vote on recommendations for use of the updated vaccines.

The two shots are the 2023-2024 formulations of mRNA vaccines from Moderna and Pfizer-BioNTech, both of which target the recent omicron subvariant XBB.1.5. The FDA granted full approval of both Pfizer-BioNTech’s updated vaccine (Comirnaty) and Moderna’s updated vaccine (Spikevax) for use in those ages 12 years and up. The agency issued emergency use authorizations for both updated vaccines for use in children ages 6 months to 11 years.

If CDC and its advisors sign off on use of the vaccines Tuesday—which is likely—the shots could become fully available at local pharmacies and doctor’s offices in the coming days. While the FDA timed today’s actions to boost the population ahead of an anticipated winter wave of infection, the regulatory clearance come amid a mild increase of COVID-19 transmission that began in late summer.