BRUSSELS - The European Union's drug regulator on Thursday backed two separate Covid-19 vaccine boosters updated to target the Omicron variant and developed by Moderna and the team of Pfizer and BioNTech.

Europe is preparing to roll out shots ahead of an anticipated rise in infections this winter. The new so-called bivalent shots combat the BA.1 version of Omicron and the original virus first detected in China.

The recommendation is to authorise the vaccines for people aged 12 years and above who have received at least primary vaccination against Covid-19, the European Medicines Agency (EMA) said.

The final go-ahead will be subject to European Commission approval, which is expected to come in shortly.

Britain in August became the first country to clear the Moderna bivalent shot. Switzerland and Australia quickly followed suit.

The latest EMA recommendations come as Pfizer's booster retooled to target the currently dominant BA.4/BA.5 variants along with the ancestral coronavirus strain has already been submitted for EU review, while Moderna's submission is imminent.

The EMA is expected to also offer its opinion on BA.4/5 adapted vaccines in the coming weeks, European Commissioner for Health and Food Safety Stella Kyriakides said in a statement on Thursday.

EU officials signalled in recent months they were open to initially using shots targeting the older BA.1 variant, given those specifically targeting newer Omicron offshoots BA.4/5 are further behind in development.

Given BA.1 emerged first, data from human trials testing the adapted vaccines from sets of developers has been submitted to EU regulators.

US and Canada approvals

Europe's move comes as advisers to the US Centres for Disease Control and Prevention (CDC) on Thursday voted to recommend the use of Covid-19 booster shots redesigned to target the BA.4 and BA.5 Omicron subvariants of the coronavirus for people aged 12 years and older.

The CDC’s Advisory Committee for Immunisation Practices voted 13-to-1 in favour of the updated boosters by Pfizer-BioNTech and Moderna.

The vote is one of the last steps before millions of the retooled shots roll out by the end of this weekend as part of a nationwide revaccination campaign. The agency’s director Rochelle Walensky will make the final call after the meeting. He has been supportive of a booster campaign in recent public statements.

On Wednesday, the US Food and Drug Administration (FDA) authorised the updated shots from Pfizer-BioNTech and Moderna that target the dominant BA.4 and BA.5 Omicron subvariants as well as the original virus. They are often called bivalent shots.

FDA officials on Wednesday said they believe the updated shots should be available to a broader population than the previous boosters as they may help younger people avoid long-Covid, which can leave them suffering debilitating symptoms for months.

The FDA authorised the Pfizer-BioNTech shots for people age 12 and older and the Moderna booster for those 18 and over, if they have received a primary vaccine series or a booster at least two months prior. The previously authorised monovalent vaccine will no longer be available as a booster shot in those age groups.

Pfizer said on Thursday it hopes to ask the FDA for authorisation in five- to 11-year-olds in early October.

CDC and FDA officials have said they believe the shots will boost immunity against the virus ahead of the winter season, when infections tend to rise as people spend more time indoors where the virus is more easily transmitted.

Currently, a second booster is restricted largely to people over age 50 and those who are immunocompromised or at high risk.

During the meeting, CDC officials suggested people who have had Covid-19 should wait at least until they have completed their isolation to receive a booster and may consider waiting three months.

Vaccine makers have yet to complete human trials for the newly authorised boosters, and some members of the CDC's Advisory Committee for Immunisation Practices raised reservations over the lack of data. Most of the available data on the redesigned boosters comes from lab and animal studies.

Canada on Thursday also authorised Moderna's bivalent Covid-19 shots for adults, adding the first Omicron-adapted vaccine to its arsenal just as falling temperatures are poised to force people indoors where the risk of infection is higher.

Regulator Health Canada said in a statement that Moderna’s bivalent Spikevax booster was safe and effective, while also generating a good immune response against the Omicron BA.4 and BA.5 sub-variants.

Canada has secured 12 million doses of the new vaccine booster, and Moderna will start delivering them from Friday. REUTERS