How people could get ‘mix and match’ Covid vaccines: UK scientists will trial giving people multiple types of jab to boost different parts of their immune systems
- Taskforce’s Kate Bingham said ‘you ideally want to have both’ immunity types
- Scientists plan to trial combinations of Pfizer, Oxford and Moderna vaccines
- Small trials lasting only a couple of months are set to happen in the new year
- Some jabs produce strong antibody response while others make T cells
Brits could get ‘mix and match’ coronavirus vaccines to try and stimulate different parts of their immune systems.
Scientists on the country’s Vaccine Taskforce yesterday said they would trial giving people a dose of one type of jab and then a booster with a different type.
All the vaccines that are close to approval – or already over the line – in Britain need two doses each to be most effective at preventing Covid-19.
But, because they work in different ways, getting doses of different jabs could ‘maximise’ the immune response and give better, longer lasting protection.
Chief of the UK Vaccine Taskforce, Kate Bingham, said researchers in the UK would start trials of this method, known as ‘heterologous prime-boost’, next year.
Britain will today become the first country in the world to start vaccinating the public against Covid-19 with a jab made by Pfizer and BioNTech, which was approved by the MHRA regulator after clinical trials suggested it was up to 95 per cent effective.
Two more vaccines – by Oxford University and AstraZeneca, and US pharmaceutical company Moderna – have also had successful clinical trials. Oxford’s is expected to be given out by the NHS before the end of the year.
Kate Bingham, chair of the UK Vaccine Taskforce, is pictured after having a coronavirus vaccine made by the US company Novavax, as part of a clinical trial
Any coronavirus vaccine available from Europe before the end of the year will be able to make it to the UK before Brexit, the manufacturing lead for the UK’s vaccine taskforce has said.
While the UK leaving Europe adds ‘complexity’ to the process, robust plans are in place to mitigate Brexit.
The first doses of the Pfizer/BioNTech vaccine have already arrived from Belgium, and if approved, the initial doses of the Oxford jab are due to be dispatched from Germany to the UK.
Later batches of the Oxford vaccine will be manufactured in the UK.
Ian McCubbin, manufacturing lead for the taskforce, said: ‘All the vaccines that will be available prior to Christmas, and the end of the year, will get to the UK so that we get them into the country while we’re still in Europe
‘In the very very short term we will bring these vaccines into the country before Brexit actually happens.’
Speaking at a press briefing, Steve Bates, chief executive of the BioIndustry Association, added: ‘I think in terms of Brexit it’s a known risk that we’ve been managing in this programme, along with many, many others.
‘Of course, it adds complexity to the process, but there is a robust plan for alternative routes, and mitigation for those, in place.
‘They’ve not being tested yet but we’ve been working on them for some time.’
The UK has secured more than 350 doses of seven different vaccines, including 40 million doses of the Pfizer/BioNTech vaccine, and 100 million doses of the jab developed by Oxford and AstraZeneca.
Ms Bingham and colleagues on the UK’s Vaccine Taskforce revealed their plans for the mix-and-match trial in a briefing on Monday.
They said the idea was ‘not rocket science’ and that it was a long-standing theory that vaccines would work better this way, but it hadn’t been trialled in the real world.
Small trials taking only around two months could be organised, they said, with people only getting vaccines that were proven to be safe and effective on their own.
Only vaccines approved by the Government could be used, said the deputy chair of the Taskforce, medicines discovery expert Dr Clive Dix.
The thinking behind it is different vaccines provoke different parts of the immune system – the main substances being antibodies and T cells.
Ms Bingham said: ‘You’d do a prime with one vaccine, as in your first jab would be with one vaccine format, and then the second – whether it’s 28 days or two months, or whatever the agreed period would be – would be with a different vaccine.
‘The reason to do that is, for example, the viral based vaccines trigger a much greater cellular response than, say, mRNA.
‘Antibodies block the uptake of viruses into cells, and the T cells identify those cells that have been infected and then take them out, so you ideally want to have both.
‘So the idea of trying to mix and match is so that you can maximise the strength of that immune response to protect people against viral infection.’
In the same briefing, members of the Taskforce said:
- The approval of the world’s first mRNA vaccine is ‘the most exciting thing that’s happened in vaccinology for a long time’, said Dr Clive Dix;
- There are already more than four million doses of the Oxford/AstraZeneca vaccine ready to go in the UK, and official approval is expected this month;
- Covid vaccines could become an annual necessity if the virus sticks around for years to come and could be rolled into one with the flu jab, Ms Bingham said;
- People who get coronavirus vaccines will be monitored for years to see whether they develop side effects or whether immunity wears off;
- Brexit will add ‘complexity’ to shipping vaccines from Europe but supplies in 2020 will not be affected, said manufacturing expert Ian McCubbin.
The Pfizer and BioNTech vaccine is one called an mRNA vaccine. It is the first of its kind to ever be approved and works by injecting genetic material from the coronavirus into the body inside a droplet of fat.
This genetic material is then naturally absorbed by cells which it forces to produce the ‘spike’ proteins found on the outside of the virus.
This makes it look like the coronavirus and so triggers an immune response in the same way that being infected with the real thing would.
Moderna’s vaccine works in the same way.
Oxford and AstraZeneca’s, however, is a more traditional type of jab that carries the genetic material in a harmless chimpanzee virus, called an adenovirus, instead of the fat droplet.
Ms Bingham added: ‘Chadox [Oxford’s vaccine], in fact, was developed for that… so there’s nothing hugely rocket science about this it’s just that we have the ability to explore it and we’re going to do that.’
Dr Dix, who works as CEO of medicine discovery firm C4X Discovery, explained that researchers would start by trying combinations of Pfizer’s, Oxford’s and Moderna’s jabs if they are all approved by the MHRA.
‘We can only do it with approved vaccines,’ he said.
‘The idea is that it’s always been thought that heterologous prime-boost will give you a better immune response but no-one’s ever done it live.
‘Since we have safe vaccines available we should do that study because then we have the ability to actually produce better immune responses.’
HOW DO THE OXFORD, MODERNA AND PFIZER/BIONTECH VACCINES COMPARE?
Moderna and Pfizer/BioNTech have both released interim results of the final stage clinical trials of their vaccines, with both suggesting they are extremely effective.
Oxford University has published the findings from its second phase, which show the jab provokes an immune response and is safe to use – it is not yet clear how well it protects against coronavirus in the real world.
Here’s how they compare:
PFIZER (US) & BIONTECH (DE)
OXFORD UNIVERSITY (UK)
How it works:
mRNA vaccine – Genetic material from coronavirus is injected to trick immune system into making ‘spike’ proteins and learning how to attack them.
mRNA vaccine – both Moderna’s and Pfizer and BioNTech’s vaccines work in the same way.
Recombinant viral vector vaccine – a harmless cold virus taken from chimpanzees was edited to produce the ‘spike’ proteins and look like the coronavirus.
How well does it work?
94.5% effective (90 positive in placebo group, 5 positive in vaccine group) .
95% effective (160 positive in placebo group, 8 positive in vaccine group).
62% – 90% effective, depending on dosing.
How much does it cost?
Moderna confirmed it will charge countries placing smaller orders, such as the UK’s five million doses, between £24 and £28 per dose. US has secured 100million doses for $1.525billion (£1.16bn), suggesting it will cost $15.25 (£11.57) per dose.
The US will pay $1.95bn (£1.48bn) for the first 100m doses, a cost of $19.50 (£14.80) per dose.
Expected to cost £2.23 per dose. The UK’s full 100m dose supply could amount to just £223million.
Can we get hold of it?
UK has ordered five million doses which will become available from March 2021. Moderna will produce 20m doses this year, expected to stay in the US.
UK has already ordered 40million doses, of which 10million could be available in 2020. First vaccinations expected in December.
UK has already ordered 100million doses and is expected to be first in line to get it once approved.
What side effects does it cause?
Moderna said the vaccine is ‘generally safe and well tolerated’. Most side effects were mild or moderate but included pain, fatigue and headache, which were ‘generally’ short-lived.
Pfizer and BioNTech did not produce a breakdown of side effects but said the Data Monitoring Committee ‘has not reported any serious safety concerns’.
Oxford said there have been no serious safety concerns. Mild side effects have been relatively common in small trials, with many participants reporting that their arm hurt after the jab and they later suffered a headache, exhaustion or muscle pain. More data is being collected.
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