Pfizer vaccine neutralizes Brazilian virus variant in new study

The Pfizer vaccine was able to neutralize a coronavirus variant first identified in Brazil in a new lab study, a positive sign for the vaccine’s effectiveness.

Neutralization of the Brazilian variant, known as P.1, was “roughly equivalent” to the original strain of the virus, which the Pfizer vaccine has been shown to be highly effective against, researchers wrote in a letter to The New England Journal of Medicine.

The P.1 variant has provoked some concern given the surge in cases it is fueling in Brazil.

Anthony Fauci, the top U.S. infectious disease expert, said in a presentation last week there are “preliminary reports” the variant is more infectious, and that antibodies produced by vaccines “may be less effective.”

The results published Monday from researchers from Pfizer, its German partner BioNTech, and the University of Texas Medical Branch, however, are reassuring.

The study also found strong neutralization of the B.1.1.7 variant, first identified in the U.K., though that was already expected.

Perhaps a more concerning variant: The B.1.351 variant, first identified in South Africa, has raised concern for its potential ability to weaken the effectiveness of vaccines to some degree. The study found neutralization of that variant was “robust but lower.”