Pfizer/BioNTech Vaccine Works Against Covid-19 Variants: Study

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The Covid-19 vaccine developed by Pfizer and BioNTech is effective against against a Brazilian variant of the virus, according to researchers published by the New England Journal of Medicine.

Its “neutralization” of the variant “was roughly equivalent” to its ability to suppress the main strain in the United States, according to the scientists, who published their findings in a Monday letter to the journal. They said its efficacy against a South African variant was “robust but lower.”

The letter’s signatories included 16 American researchers and two Germans.  “We see high neutralizing activity against all strains tested, including P.1 that is spreading so rapidly in Brazil,” University of Washington biology professor Carl Bergstrom noted in a message explaining the letter on Twitter. “While activity is diminished against the B.1.351 strain from South Africa, it is still very impressive.”

The Pfizer/BioNTech vaccine became the first approved for use in the U.S. in December, though without research indicating whether it would be effective against different strains of the virus, which have proven resilient against some vaccines. South Africa halted trials for a vaccine developed by AstraZeneca-Oxford in February after determining it was mostly ineffective, while a vaccine developed by Novavax had a reported efficacy rate of 49 percent against that country’s predominant strain.

One more company, Johnson & Johnson, did conduct testing to account for the new variants of the virus. The company said those trials indicated its vaccine was 72 percent effective in the United States, 66 percent in South America, and 57 percent in South Africa. The Food and Drug Administration approved that company’s vaccine last month.