For the study, researchers from Pfizer and the University of Texas Medical Branch genetically engineered versions of the virus to carry some of the mutations found in B.1.351. They tested it on blood samples taken from 15 people who received two doses of Pfizer / BioNTech vaccine as part of a clinical trial.
While the blood serum samples produced less neutralizing antibody activity, it was still enough to neutralize the virus, they write in a letter to the journal. This is in line with other studies. And it’s good inside what’s seen with other viruses, one of the researchers said.
“Although we do not yet know exactly what level of neutralization is required for protection against COVID-19 disease or infection, our experience with other vaccines suggests that the Pfizer vaccine is likely to provide relatively good protection against this new variant,” he said. Scott said. Weaver, director of the Institute of Human Infections and Immunity at the University of Texas Medical Branch and an author of the study, told CNN.
“The reduction in neutralization levels compared to the South African variant of about 2/3 is quite small compared to the variations in neutralization levels generated by vaccines against other viruses whose protein sequences are even more variable than SARS-CoV-2,” Weaver added.
Pfizer said there is no real-life evidence that the variant escapes the protection offered by the vaccine. Nevertheless, Pfizer and BioNTech are taking the necessary steps, making the right investments, and engaging in appropriate discussions with regulators to be able to develop authorization and search for an updated mRNA vaccine or booster as soon as it is a strain which significantly reduces the protection of the vaccine, ”Pfizer said in a statement.
Separately, a team from the National Institutes of Health and Moderna published a letter in the same journal outlining the findings from an experiment they reported last month. They also showed a reduction in the antibody response to genetically engineered viruses to look like the B.1.351 variant – but this is not enough to make the vaccine work less effectively.
“Despite this reduction, the neutralization of titer levels remains with (the variant discovered in South Africa) above the levels that are expected to be protective,” the company said in a statement.
They found no reduction in efficacy compared to a variant first seen in the UK and known as B.1.1.7.