San Francisco Frontiers - EU watchdog approves vaccine targeting Omicron sub-variants

The so-called "bivalent" jab, made by Pfizer/BioNTech, is directed at the highly infectious BA.4 and BA.5 types of the variant and is the first of its kind to be approved within the 27-nation bloc.

"This recommendation will further extend the arsenal of available vaccines to protect people against Covid-19 as the pandemic continues and new waves of infections are anticipated in the cold season," the European Medicines Agency (EMA) said.

The vaccine also targets "the original strain of SARS-CoV-2" and comes 11 days after the Amsterdam-based drug watchdog approved vaccines by Pfizer and Moderna against the Omicron BA.1 variant.

The latest shot is aimed at people over 12 and who have already received at least one primary vaccination against the coronavirus, and it is an adaptive version of Pfizer's original Comirnaty vaccine.

European nations have been keen to rush through the new generation of jabs so they can start booster campaigns ahead of a feared Covid surge in the latter part of this year.

The latest vaccines "better match the circulating variants of SARS-CoV-2 and are expected to provide broader protection against different variants," the EMA said.

"Prompt assessment of the available data on these adapted vaccines will enable their timely deployment in the autumn vaccination campaigns," it added.

The EMA's recommendation -- which will now be sent to the European Commission for a final decision -- was specifically based on clinical data from Pfizer's vaccines aimed at the original virus and the Omicron BA.1 variant.

- New wave feared -

"Apart from containing mRNA matching different, but closely related, Omicron sub-variants, Comirnaty Original/Omicron BA.4-5 and Comirnaty Original/Omicron BA.1 have the same composition," the EMA said.

Pfizer's vaccine works on the principle of tiny molecules carrying instructions for the human body to temporarily produce spike proteins similar to those found on the coronavirus -- and which it uses to enter the body's cells.

The body's immune system recognises the spike protein as foreign and activates natural defences against them.

When a person then comes in contact with the real virus, the body's immune system will also recognise and attack it.

The United States authorised its first anti-Omicron vaccines late last month, approving Pfizer and Moderna jabs for the BA.4 and BA.5 strains.

Britain authorised the Moderna vaccine for the BA.1 type in mid-August.

While the original vaccines, approved nearly two years ago provided some protection against newer coronavirus variants, the race had been on to come out with a newer group of vaccines that also target the milder but more infectious Omicron strains.

While previous "variants of concern" like Alpha and Delta eventually petered out, Omicron and its sub-lineages have dominated throughout 2022.

The BA.4 and BA.5 types have in particular helped to drive a wave of new cases of the disease in Europe and the United States in recent months.

All Omicron variants tend to have a milder disease course as they settle less in the lungs and more in the upper nasal passages, causing symptoms like fever, tiredness and loss of smell.

jhe/rox

M.Powell--SFF