Pfizer and BioNTech have applied for Emergency Use Authorization (EUA) for a fourth dose of their Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine for children aged six months to four years.

The Omicron-adapted bivalent vaccine is currently authorized for these ages as a third dose in a three-dose primary vaccination series.

If the new application is authorized, the children in this age group would be eligible to receive a fourth dose at least two months after the primary vaccination series.

The submission is supported by study data showing a higher Omicron BA.4/BA.5 neutralizing response from a fourth, bivalent dose compared with three doses of the companies’ original COVID-19 vaccine.