The European Medicines Agency said on Tuesday (Dec 6) its emergency task force has concluded that messenger RNA bivalent COVID-19 vaccines, targeting the original strain and the Omicron BA.4-5 subvariants, may be used in previously unvaccinated children and adults.
The recommendation is based on data which shows that primary vaccination with the adapted bivalent vaccines should give rise to a broad immune response in people who have not yet been exposed to or vaccinated against COVID-19, the agency added.
The EMA said it also studied the immune response in unvaccinated people after natural infection with Omicron BA.4/5 strains of the virus.
The safety profile of the adapted vaccines when used as boosters is comparable to that of the original messenger RNA vaccines.
The US Food and Drug Authority (FDA), which did not immediately respond to a Reuters request for comment, is yet to recommend the bivalent shots for initial vaccination against the virus.
The use of the so-called bilavent shots by Pfizer and BioNTech, as well as rival Moderna , is recommended as a booster in the European Union and in United States.