Pfizer and BioNTech have requested authorization from the Food and Drug Administration to give booster doses of their COVID-19 vaccine to children ages 5 to 11, the companies jointly announced on Tuesday.

The announcement comes about two weeks after the companies reported a third shot sparked a strong immune response in children in that age group. The phase 2/3 clinical trial found that the booster raised antibodies against the omicron variant thirty-sixfold compared to levels seen after two shots.