FDA Grants Emergency Use Authorization to Pfizer-BioNTech Bivalent COVID-19 Booster in Children Under 5 Years

The BA.4/BA.5-adapted bivalent COVID-19 vaccine from Pfizer and BioNTech has been granted Emergency Use Authorization (EUA) by the FDA in children 6 months through 4 years of age, at least 2 months after completion of primary vaccination with 3 doses of the Pfizer-BioNTech COVID-19 original vaccine.¹

The bivalent booster is also authorized as the third dose of a 3-dose primary series. For children who receive the bivalent booster as a third dose, a fourth booster dose is not authorized at this time.¹

The most recent real-world evidence shows that Omicron BA.4/BA.5-adapted bivalent vaccines appear to be protective against symptomatic COVID-19 in adults caused by both the BA.4/BA.5 and XBB Omicron sublineages, the latter of which currently accounts for more than 85% of COVID-19 cases in the United States, according to a press release.¹

Additional real-world evidence collected between September 2022 and December 2022 shows that among older adults, receiving an mRNA-based bivalent booster provided greater vaccine efficacy against COVID-19 hospitalization compared to receiving 2 or more doses of the original wild-type vaccine administered 2 months earlier. This was observed during a period when different Omicron sublineages were circulating, including XBB.1.5, which began circulating in the second half of December 2022.¹

The EUA is based on data from sub-studies within the companies’ phase 1/2/3 study evaluating this fourth dose in 300 children 6 months through 4 years of age. Safety and immunogenicity were evaluated in a subset of 60 participants, demonstrating that the fourth dose of the bivalent vaccine elicited improved Omicron BA.4/BA.5-neutralizing antibody responses compared to participants who received 3 doses of the original vaccine. The safety and tolerability were similar to the original vaccine.¹

Pfizer and BioNTech also submitted an application to the European Medicines Agency to extend the Omicron BA.4/BA.5-adapted bivalent vaccine’s marketing authorization to include use in children 6 months through 4 years of age as both the primary 3-dose series and a booster vaccine. Currently, the bivalent vaccine is authorized in the European Union as a booster dose for ages 5 years and older.¹

Vaccinating children against respiratory illnesses has been a major focus in recent months, as seasonal respiratory illnesses in young children have strained health systems. Updated COVID-19 vaccines may improve protection against severe illness and hospitalization in this young age group.²

“This authorization offers an opportunity for parents to help better protect their young children against COVID-19, including disease caused by Omicron sublineages,” said Albert Bourla, DVM, PhD, chairman and CEO of Pfizer, in a press release following the FDA authorization of the BA.4/BA.5-adapted bivalent vaccine as a third dose in the primary series. “Nearly 40 million Americans have received a booster dose of an updated vaccine. It is critical that we all continue to do our part to help protect ourselves by staying up to date with COVID-19 vaccinations, as recommended by public health authorities.”²

REFERENCES

1. Pfizer and BioNTech Receive US Emergency Use Authorization of Omicron BA.4/BA.5-Adapted Bivalent COVID-19 Booster in Children Under 5 Years. News release. Pfizer. March 14, 2023. Accessed March 15, 2023. https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-receive-us-emergency-use-authorization
2. Pfizer and BioNTech Receive US FDA Emergency Use Authorization for Omicron BA.4/BA.5-Adapted Bivalent COVID-19 Vaccine in Children Under 5 Years. News release. Pfizer. December 8, 2022. Accessed March 15, 2023. https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-receive-us-fda-emergency-use-2