February 8, 2021

expert reaction to study on neutralisation of mutations present in the spike protein of SARS-CoV-2 variants by the Pfizer vaccine

A study published in Nature Medicine looks at neutralisation of SARS-CoV-2 variants with key spike protein mutations by Pfizer/BioNTech COVID-19 vaccine-elicited sera.

Prof Lawrence Young, Virologist and Professor of Molecular Oncology, University of Warwick, said:

“The blocking effect of antibodies induced by vaccination with the Pfizer/BioNTech vaccine is preserved against both the UK and South African variants.

“This study shows that SARS-CoV-2 viruses engineered  to carry the key mutations found in the UK and South African variants are effectively neutralised by sera from

individuals vaccinated with BNT162b2. It confirms previous studies indicating that this vaccine is very likely to be effective against the UK variant. It shows that the mutations found in the South African variant reduced the efficiency of virus neutralisation by 50% but only in six out of the 20 sera examined. There is no explanation for the variability observed in the blocking effect of sera from different individuals. The study used engineered viruses which did not contain the full range of spike mutations found in the UK or South African variants. A previous study found more significant reductions in the ability of convalescent sera from COVID-19 patients to neutralise the South African variant.

“A major issue with these different studies is the difficulty in comparing results from the different virus blocking assays employed and the associated lack of a serological correlate of protection against COVID-19.”

Prof Jonathan Ball, Professor of Molecular Virology, University of Nottingham, said:

“This is important work and provides reassurance that the antibody response generated by the Pfizer vaccine is able to neutralise Sars2 coronavirus genetically engineered to carry some of the mutations seen in the variants of concern first identified in the UK and South Africa.

“However, we suspect that the effects of these mutations can be influenced by mutations occurring in other parts of the spike protein, so it will be important to validate these promising findings using viruses engineered to carry all of the mutations found in each variant.”

‘Neutralization of SARS-CoV-2 spike 69/70 deletion, E484K and N501Y variants by BNT162b2 vaccine-elicited sera’ by Xuping Xie et al was published in Nature Medicine on Monday 8 February

All our previous output on this subject can be seen at this weblink:

www.sciencemediacentre.org/tag/covid-19

Declared interests

Prof Jonathan Ball: “Receives UKRI funding to develop DNA-based Covid vaccines.”

None others received.