The Covid-19 vaccine from Pfizer and BioNTech appears to protect against a mutation in two coronavirus variants that are causing rapid spread across the UK, new research suggests.
The pharmaceutical company and researchers from the University of Texas medical branch carried out lab tests on the variants, one of which was found in the UK while the other originated in South Africa.
Both contain mutations including N501Y, an alteration in the spike protein of the virus, which is a target for vaccines.
In the study, which has not yet been peer-reviewed, blood samples were taken from 20 people who received the Pfizer/BioNTech vaccine.
Laboratory studies found that the samples had neutralising levels of antibodies which appeared to work against N501Y in the new variants. However, one of the mutations in the South Africa one, named E484K, has not yet been studied.
Pfizer said it had now tested 16 different mutations in the strains and none of them have had any significant impact on how the vaccine works.
Further studies are planned on the other mutations.
Earlier this week, the UK’s chief scientific adviser, Sir Patrick Vallance, said it might be that the new strains reduce the efficacy of vaccines but that more studies were needed.
Scientists gave the study a cautious welcome but said further research was needed.
Daniel Altmann, professor of immunology at Imperial College London, said: “This is indeed an important finding to calm any concerns about lack of vaccine coverage for the variants.”
He added that “neutralisation of the variant looks excellent from this study”.
Ravi Gupta, professor of microbiology at the University of Cambridge, said the research was lacking and looked at only one mutation “which was not expected to have significant impact alone”.
Eleanor Riley, professor of immunology and infectious disease at the University of Edinburgh, said: “So far, so good. There will be other new mutants and we will need to monitor the situation carefully by repeating this type of study on new variants as they appear. It may be necessary to tweak the vaccine over time.
“To inject a little optimism into the discussion: there is a limit to the number of mutations the virus can accumulate and still be able to bind to the receptor (which allows the virus to infect people).”
Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said: “This is good news, mainly because it is not bad news.
“Had the opposite result been found, that the vaccine did not seem to have efficacy against the variation of the virus studied, that would have been bad and very concerning.
“So, yes this is good news, but it does not yet give us total confidence that the Pfizer (or other) vaccines will definitely give protection.
“We need to test this in clinical experience and the data on this should be available in the UK within the next few weeks.”
Quick guide How does the Pfizer/BioNTech Covid-19 vaccine work?
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The Pfizer/BioNTech Covid jab is an mRNA vaccine. Essentially, mRNA is a molecule used by living cells to turn the gene sequences in DNA into the proteins that are the building blocks of all their fundamental structures. A segment of DNA gets copied (“transcribed”) into a piece of mRNA, which in turn gets “read” by the cell’s tools for synthesising proteins.
In the case of an mRNA vaccine, the virus’s mRNA is injected into the muscle, and our own cells then read it and synthesise the viral protein. The immune system reacts to these proteins – which can’t by themselves cause disease – just as if they’d been carried in on the whole virus. This generates a protective response that, studies suggest, lasts for some time.
The two first Covid-19 vaccines to announce phase 3 three trial results were mRNA-based. They were first off the blocks because, as soon as the genetic code of Sars-CoV-2 was known – it was published by the Chinese in January 2020 – companies that had been working on this technology were able to start producing the virus’s mRNA. Making conventional vaccines takes much longer.
Adam Finn, professor of paediatrics at the Bristol Children’s Vaccine Centre, University of Bristol
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Dr Alexander Edwards, from the University of Reading, said more studies were needed but the data was “extremely encouraging”. “This is exactly the kind of data that is needed to better understand how any mutation or variant might affect vaccine function.
“The experiment described takes blood serum from volunteers immunised with the Pfizer/BioNTech vaccine and shows that it has equal ability to block one of the important mutations in the two concerning variant virus forms, as it does to block the original virus,” he said.
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