UK Covid: Mix-and-match vaccines trialled in world first

A group of 800 volunteers are being recruited (Picture: PA)

Downing Street has launched the world’s first trial into whether mixing and matching Covid  vaccines is safe and can enhance protection against the disease.

A group of 800 volunteers are being recruited to try the Oxford and Pfizer vaccine in combination instead of using the same jab for first and second doses.

It is hoped the ‘mix and match’ approach could stimulate different parts of the immune system and give better, longer lasting immunity. 

Scientists will trial other vaccine combinations as more are approved over the course of the year-long research.   

Mixing vaccines could also help the UK deal with supply shortages which has held back the vaccination rollout here and abroad.

The programme, which has received £7 million 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.

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.

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‘Given the inevitable challenges of immunising large numbers of the population against Covid-19 and potential global supply constraints, there are definite advantages to having data that could support a more flexible immunisation programme, if needed and if approved by the medicines regulator,’ he said.

‘It is also even possible that by combining vaccines, the immune response could be enhanced giving even higher antibody levels that last longer; unless this is evaluated in a clinical trial we just won’t know.’

It 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.

10 million Brits – about a fifth of the adult population – had received a first dose as of yesterday, edging the UK closer to its target of vaccinating the four most vulnerable groups by mid-Feb.

Doctor Anil Mehta gives the AstraZeneca vaccine to a homeless person

Doctor Anil Mehta gives the Oxford vaccine to a homeless person at the homeless accommodation YMCA in Romford, east London (Picture: AP)

It was reported this week that all adults could get their first dose by the end of May and the second by the end of August, but at a No 10 news conference on Wednesday Whitty said this was ‘very optimistic’.

Initial results of the ‘mix and match’ study are expected to become available during the summer – in time to inform policy on the use of booster vaccines among younger age groups.

UK regulators have so far only approved giving patients two doses of the same vaccine and the new study will not impact anyone currently being invited for a jab.

Currently the Oxford University/AstraZeneca and Pfizer/BioNTech Covid vaccines are the only two being rolled out in the UK, but the Moderna one has also been approved and is expected to become available by Spring.

Two other vaccines made by Johnson and Johnson and Novavax are on the cusp of being approved and several more candidates are in late stage trials.

Vaccines minister Nadhim Zahawi said: ‘This is a hugely important clinical trial that will provide us with more vital evidence on the safety of these vaccines when used in different ways.’

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