The UK Medicines and Healthcare products Regulatory Agency (MHRA) has approved a new version of Moderna's 'bivalent' COVID-19 Spikevax booster, the second bivalent booster vaccine from this manufacturer.
The UK medicines regulator said that 50% of the adapted vaccine dose targets the original SARS-CoV-2 and 50% the Omicron BA.4 and BA.5 sub-variants. The original bivalent Spikevax, containing a 50/50 mix of the original vaccine plus a vaccine candidate targeting Omicron, was given conditional authorisation last August and deployed in the autumn booster campaign last year.
Last year's campaign also featured an adapted bivalent version of the Comirnaty vaccine from Pfizer/BioNTech that targeted both the original virus strain and Omicron BA.1.
The MHRA said that the updated bivalent Spikevax booster had been approved after "a careful review of the evidence" showed that it met the regulator’s "standards of safety, quality, and effectiveness", and based on the advice of the Commission on Human Medicines. It noted that: "The common side effects observed with the new bivalent vaccine were the same as those seen for other versions of the vaccine. These side-effects were typically mild and self-resolving, with no new safety concerns identified."
The new line extension granted by the MHRA is valid in Great Britain only and was authorised via the European Commission (EC) Decision Reliance Route, in which the MHRA considers the marketing authorisation application made by the company together with due consideration of the decision made by the European Medicines Agency's Committee for Medicinal Products for Human Use.
The new bivalent vaccine can be used as a booster in individuals aged 12 years and older who have previously received at least a primary vaccination course against COVID-19. The aim of the boosters was to "help to improve the protection obtained from earlier doses of the vaccine and help give longer-term protection against getting seriously ill from COVID-19", the MHRA said.
Last month, the Joint Committee on Vaccination and Immunisation (JCVI) published interim advice for the 2023 vaccination season. The JCVI said its goals continued to be "the reduction of severe disease across the population, while protecting the NHS".
Most People Now Immune
It noted that there is currently a high level of population immunity from vaccination and/or natural infection, with over 97% of adults in England estimated to have SARS-CoV-2 antibodies by the end of August 2022. In addition, in Great Britain, the same applied to an estimated 93-99% of children aged 12-15 years, and 74-98% of children aged 8-11 years.
"Natural immunity alone provides good levels of protection against severe COVID-19," the JCVI said, while averring that hybrid immunity from both natural and vaccine-induced antibodies was associated with even higher levels of protection.
In the light of recent immunity figures, the UK Health Security Agency (UKHSA) recently revised its estimates of the numbers needed to vaccinate to prevent one COVID-related hospitalisation during the Omicron era to 800 for persons aged 70 years and older; 8000 for 50- to 59-year-olds, and 92,500 for people aged 40-49 years and not in a clinical risk group.
Vaccine Uptake 'has Plateaued'
The announcement also comes in the face of falling vaccine uptake. Uptake of primary course vaccination "has plateaued in recent months across all age groups", the JCVI said. "Since the beginning of 2022, less than 0.01% of eligible individuals per week over the age of 12 years, received a first COVID-19 vaccine dose."
In addition, since April 2022, uptake of initial booster doses has also been less than 0.1% per week in all eligible people under 50 years of age. "Based on the current data, keeping the booster (third dose) offer open to these groups is considered of limited ongoing value and the overall impact on vaccine coverage is negligible."
"Primary course COVID-19 vaccination should move, over the course of 2023, towards a more targeted offer during vaccination campaigns to protect those persons at higher risk of severe COVID-19," the JCVI said. Those groups at higher risk of severe disease "could be offered a booster vaccine dose in preparation for winter 2023 to 2024".