The US Food and Drug Administration (FDA) says it’s okay to mix and match COVID-19 vaccines being used for a third booster shot.
The agency also authorized extension of a booster shot to anyone who received the Moderna or Johnson & Johnson vaccine.
Those who are eligible for the booster dose are permitted to use a different brand of vaccine than the one initially received, the FDA said.
The US booster campaign began last month with extra doses of the Pfizer BioNTech vaccine.
Official recommendations for who should receive booster shots, and when, will come after the Centers for Disease Control and Prevention consult an expert panel, set for Thursday.
Federal regulators also plan to meet next month to discuss the safety and effectiveness of low-dose vaccinations for children ages 5 to 11.
A CDC advisory panel is expected to meet on the matter November 2-3.
If approved, pediatric COVID-19 vaccines will be made available to some 28 million children in that age group.