A study led by researchers from the New York University, US, showed that Pfizer's vaccine against Covid-19 can effectively neutralise Beta, Gamma variant of the Coronavirus disease. The study, published in the journal mBio, also found that monoclonal antibody cocktail consisting of casirivamab and imdevimab might be less effective against SARS-CoV-2 variants in laboratory experiments.
The study found that Pfizer BNT162b2 vaccination worked well against the majority of variants as the earlier virus, but the vaccine neutralised the South African variant and the Brazil variant with a 3-fold decrease in titer.
"Our interpretation of the results is that the vaccine antibodies are very powerful, and even if you lose 3-fold of the titer, there is still plenty of antibody there to neutralize the virus. We believe the findings demonstrate that the vaccines will remain protective against the variants that we tested," said Nathaniel "Ned" Landau, Professor in the Department of Microbiology at the NYU Grossman School of Medicine, in New York City.
Lab experiments on Regeneron pharmaceuticalsaÂ¿s REGN-COV2 -- a 2 recombinant monoclonal antibody cocktail -- showed that casirivamab had lost some of its neutralising activity against the South African and Brazilian variants and the cocktail was 9- to 15-fold decreased in titer, the team said. "One of the Regeneron antibodies is affected by the E484K mutation, and as a result the cocktail loses some of its neutralizing activity," said Landau.