Pfizer-BioNTech Omicron Bivalent Booster Receives FDA Emergency Use Authorization for Children Under 5

Today, the COVID-19 vaccine manufacturing partners, Pfizer Inc. and BioNTech SE, announced the US Food and Drug Administration (FDA) granted emergency use authorization (EUA) to administer their Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine to children 6 months-4 years of age.

With this decision, children under 5 are authorized to receive the bivalent booster at least 2 months after completing a primary vaccine series (3 doses of the Pfizer-BioNTech original vaccine). The bivalent booster is also authorized as the third dose in a 3-dose primary series. Children who go this route are not authorized for a booster fourth dose at this time.

The under 5 age group is the youngest eligible for COVID-19 vaccination, and the last age group to receive EUA for the Pfizer-BioNTech bivalent booster. There was an impetus to fully approve the Omicron BA.4/BA.5-adapted bivalent vaccines to combat new and emerging COVID-19 variants.

Real-world evidence suggests the Omicron BA.4/BA.5-adapted bivalent vaccines are protective against symptomatic COVID-19 disease caused by the BA.4/BA.5 and XBB Omicron subvariants. This updated bivalent booster could provide vital protection, as the latest US Centers for Disease and Control (CDC) surveillance data estimates the XBB.1.5 strain is responsible for 89.5% of new COVID-19 infections.

The EUA was granted based on study data evaluating the immunogenicity, safety, and tolerability of the bivalent booster, administered as a fourth dose in children 6 months-4 years of age. In safety and efficacy analyses, the investigators determined a booster dose of the Omicron BA.4/BA.5-adapted bivalent vaccine induced significantly improved Omicron BA.4/BA.5-neutralizing antibody responses. Pfizer-BioNTech noted the safety and tolerability profile of the bivalent booster is similar to that of their original vaccine.

Pfizer-BioNTech originally announced they submitted an EUA application to the FDA on December 5, 2022. The companies asked to administer a 3-µg dose of their bivalent Omicron BA.4/BA.5-adapted bivalent vaccine to children under 5 years of age.

Until this latest approval, all individuals 5 years and older were authorized under EUA to receive an Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine in the US and European Union (EU). Pfizer-BioNTech’s bivalent booster may be administered at least 2 months after completing a primary vaccine series with any approved monovalent COVID-19 vaccine, or at least 2 months after receiving an approved monovalent COVID-19 booster dose.

Pfizer-BioNTech have also applied to the European Medicines Agency (EMA) to extend the marketing authorization of the Omicron BA.4/BA.5-adapted bivalent vaccine for use as both a primary series (all 3 doses) and a booster vaccination (fourth dose) in children 6 months-4 years of age. The companies intend to submit applications to regulatory agencies around the world to administer their Omicron-adapted bivalent vaccine to children under 5 years.