A study published today in the journal Nature Medicine shows that the COVID-19 vaccine developed by Pfizer with BioNTech was able to neutralize, in the laboratory, three variants of the coronavirus that appeared in the UK and South Africa – even more transmissible than the original and pointed out as major obstacles to the control of the pandemic.
The immunizer was tested against mutations N501Y (found in both countries), D614G (only in the United Kingdom) and E484K (only in South Africa) located on the spike protein, the part of the virus that connects with human cells. These variants were combined by the researchers and tested against a serological panel of 20 people who had participated in the clinical trials of the vaccine.
The study looked at antibodies acquired two or four weeks after immunization with two doses of the vaccine, over a three-week interval. It was tested both for the original strain of SARS-CoV-2, against which the immunizer had already shown 95% efficacy, and for mutant viruses.
Scientists reported that, in the end, the Pfizer / BioNTech vaccine managed to neutralize the three variants of the virus, with a small difference: the action against the E484K mutation, identified in South Africa, was slightly less than the neutralization against the mutation N501Y, also verified in the United Kingdom.
The preliminary results of the study, led by Pei-Yong Shi, from the University of Texas, and Philip Dormitzer, by Pfizer, had already been released last month, but only now have they been reviewed by other scientists and confirmed in a traditional publication.
The continued evolution of SARS-CoV-2 requires continuous monitoring of the significance of these changes for vaccine efficacy. This surveillance must be accompanied by preparations for the possibility that future mutations may require changes in vaccines,” wrote the authors.
They also recalled that changes of this type worked well for the influenza vaccine – a virus that changes every year. For COVID-19, they said, the flexibility of messenger RNA-based vaccine technology, such as Pfizer / BioNTech and Moderna, can facilitate updates.