The Pfizer-BioNTech bivalent Covid-19 vaccine single booster dose is authorised for children as young as six months to four years and is also authorised as the third dose of the three-dose-primary series in this age group


Pfizer-BioNTech’s bivalent Covid-19 vaccine authorised in US. as booster dose in children below five years (Credit: Mika Baumeister on Unsplash)

The US Food and Drug Administration (FDA) has granted emergency use authorisation (EUA) for Pfizer and BioNTech’s Omicron BA.4/BA.5-adapted bivalent Covid-19 vaccine as a booster dose in children below five years.

The bivalent vaccine is authorised for administration as a single booster dose in children as young as six months to four years, at least two months after three-dose primary vaccination.

It is also authorised as the third dose of the three-dose-primary series in this age group.

Comirnaty is the companies’ mRNA vaccine indicated for active immunisation to prevent Covid-19 in individuals aged 12 years of age and above.

It was also granted emergency use authorisation as a third primary series dose to individuals 12 years of age and older with certain kinds of immunocompromise.

FDA Centre for Biologics Evaluation and Research director Peter Marks said: “Today’s authorisation provides parents and caregivers of children six months through four years of age who received the three-dose primary series with the monovalent Pfizer-BioNTech Covid-19 vaccine an opportunity to update their children’s protection by receiving a booster dose with the Pfizer-BioNTech Covid-19 Vaccine, Bivalent.

“Currently available data show that vaccination remains the best defence against severe disease, hospitalisation and death caused by Covid-19 across all age groups, and we encourage all eligible individuals to make sure that their vaccinations are up to date with a bivalent Covid-19 vaccine.”

The FDA EUA is based on data from sub-studies within the Phase 1/2/3 study evaluating a fourth dose of the bivalent vaccine in children aged six months through four years.

In the study, the booster dose of the Omicron BA.4/BA.5-adapted bivalent vaccine elicited improved neutralising antibody responses compared to three doses of the original vaccine.

The bivalent vaccine showed a similar safety and tolerability profile to that of the original vaccine.

According to the latest real-world evidence, Omicron BA.4/BA.5-adapted bivalent vaccines showed superior protection against symptomatic Covid-19 disease.

Also, mRNA-based bivalent booster showed better vaccine effectiveness against Covid-19 hospitalisation in older adults, compared to the original wild-type vaccine.

Furthermore, Pfizer and BioNTech have submitted an application to the European Medicines Agency (EMA) to extend the bivalent vaccine marketing authorisation in this age group.

At present, the bivalent vaccine is approved in the EU as a booster dose for ages five years and older.