Approval has been granted for Moderna’s new Omicron-specific booster Covid vaccine, making the UK the first country to do so.

The Medicines and Healthcare products Regulatory Agency (MHRA) today announced that it has granted approval for Moderna’s adapted Covid vaccine, which targets both the original virus from 2020 and the Omicron variant.

It said that the bivalent vaccine has been ‘approved for adult booster doses’ after it ‘was found to meet the UK regulator’s standards of safety, quality and effectiveness’.

The Joint Committee on Vaccination and Immunisation (JCVI) will now ‘advise on how this vaccine should be offered as part of the deployment programme’, the MHRA added.

It said: ‘The decision to grant approval for this booster vaccine in the UK was endorsed by the Government’s independent expert scientific advisory body, the Commission on Human Medicines, after carefully reviewing the evidence.’

It added that its decision is ‘based on data from a clinical trial which showed that a booster with the bivalent Moderna vaccine triggers a strong immune response against both Omicron (BA.1) and the original 2020 strain’.

Half of each vaccine dose (25 micrograms) targets the original 2020 virus strain and the other half (25 micrograms) targets the Omicron variant in the new booster.

Side effects observed in safety monitoring were the same as those seen for the original Moderna booster dose and were ‘typically mild and self-resolving’ with ‘no serious safety concerns’ identified, the MHRA said.

MHRA chief executive Dr June Raine said: ‘I am pleased to announce the approval of the Moderna bivalent booster vaccine, which was found in the clinical trial to provide a strong immune response against the Omicron BA.1 variant as well as the original 2020 strain.

‘The first generation of Covid-19 vaccines being used in the UK continue to provide important protection against the disease and save lives. What this bivalent vaccine gives us is a sharpened tool in our armoury to help protect us against this disease as the virus continues to evolve.’

Professor of pharmacoepidemiology at the London School of Hygiene and Tropical Medicine Professor Stephen Evans said: ‘Whether this will be used in the UK booster programme will depend on other factors, including cost and what estimates of clinical efficacy are derived from analysis of the antibody response.’

He added that the ‘similarity’ of the new component targeting the Omicron variant to the original Moderna vaccine ‘has allowed the MHRA to authorise the vaccine based on its antibody response rather than demonstrating it prevents infections’.

He said: ‘We now know from many studies that this antibody response (neutralising antibodies) is to a degree predictive of the clinical effect in prevention of infection and hence admission to hospital or death.

‘It would take very much larger trials to show such effects conclusively, but we can be confident it is likely to show better clinical efficacy against the Omicron variants than the original vaccine alone.’

Moderna announced last month that it had ‘completed regulatory submissions’ for its new Omicron Covid vaccine and said that it could be used for autumn boosters in the UK if approved by the MHRA.

It followed clinical trials showing that the company’s updated Covid vaccine generates a strong immune response against the Omicron BA.4 and BA.5 variants.

Covid booster vaccines will be extended to people aged 50 and over this autumn alongside other at-risk groups, following a final recommendation from the JCVI last month.

A version of this article appeared in Pulse