Covid booster shots reformulated to target the BA.4 and BA.5 omicron subvariants received clearance from the Centers for Disease Control and Prevention on Thursday.
And the vaccinations could be available as early as this weekend or next week.
An independent committee on vaccines within the agency voted 13 to 1 in favor of the shots. Just a few hours later, CDC Director Rochelle Walensky signed off on the boosters, allowing pharmacies to begin administering the vaccines.
"If you are eligible, there is no bad time to get your Covid-19 booster and I strongly encourage you to receive it," Walensky said in a statement.
At this time, 171 million doses of Pfizer's and Moderna's omicron boosters have been secured by the U.S., and more than 200 million people are eligible for the vaccines, according to the CDC.
Still, CDC official Sara Oliver expressed to the committee on Thursday that there should be enough supply of the vaccines for people who'd like to receive them.
With a possible wave in the fall, the CDC and FDA are hoping the omicron shots will provide great protection against Covid infection, mild illness and severe outcomes.
The new boosters could be available at select locations by Saturday, but at other sites, they may roll in early next week, Claire Hannan, executive director of the Association of Immunization Managers, told STAT.
Pfizer's booster shots with an omicron component were approved for individuals aged 12 and up, and Moderna's omicron boosters received authorization for people aged 18 and older.
Anyone within the respective age groups approved for each vaccine is eligible to receive an omicron-specific booster shot. But people who are eligible should wait at least two months before getting vaccinated with the new booster if they've recently received their primary Covid vaccine series.
This also applies to folks who have recently received an older version of the booster shot that does not have the omicron-specific component.
Pfizer is looking to ask the Food and Drug Administration to also approve the omicron boosters for children between the ages of 5 and 11 in early October, executives of the company told the committee on Thursday.
Approval of the new BA.5 booster shots means the older formula, based on the original vaccines, will no longer be administered to people ages 12 and older.