With the COVID jab being given to more than 10 million people in the UK, scientists are now trying to determine whether different vaccines can safely be used for the first and second doses.
The programme, which has received £7m in funding from the government’s vaccine taskforce, aims to establish whether a mixed-dose vaccine regimen is better than, or a good alternative to, using two doses of the same COVID-19 jab.
The launch comes after England’s chief medical officer professor Chris Whitty warned the pace of the vaccine rollout will inevitably slow as more people get their second jab.
Crucially, vaccines minister Nadhim Zahawi said the study would not impact on the current rollout.
He told Sky News: “It will report probably after the summer and of course it will have no impact on the deployment.
“If you have currently had the Pfizer/BioNTech vaccine, you will get your Pfizer/BioNTech vaccine as your second dose, your booster dose.
“And of course if you have the Oxford/AstraZeneca vaccine, you’ll get the Oxford/AstraZeneca vaccine.”
He added: “If we understand more about how we can use vaccines together then we should be in a much stronger position in terms of vaccinating the United Kingdom, but also the rest of the world.”
On Wednesday, Boris Johnson hailed the “colossal” effort by health workers in getting a first jab to more than 10 million people – almost a fifth of the adult population – across the four nations.
England’s deputy chief medical officer professor Jonathan Van-Tam, who is the senior responsible officer for the new study, said that being able to mix vaccines would give them greater flexibility in future.
The study, dubbed Com-Cov, will initially look at mixing doses of the Oxford University/AstraZeneca and Pfizer/BioNTech vaccines, before moving onto other jabs as they come onto the market.
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