A new study suggests that the Pfizer-BioNtech Covid-19 vaccine can protect people against the concerning coronavirus variant first identified in Brazil.

Blood serum samples from people who had received two doses of the Pfizer-BioNtech vaccine “efficiently” neutralized a version of the virus engineered to carry the same mutations as the variant, known as the P.1.

For the study, published by the New England Journal of Medicine on Monday, researchers at Pfizer, BioNTech and the University of Texas Medical Branch genetically engineered the virus to create versions carrying mutations found in a range of coronavirus variants, including P.1.

They tested them against blood samples taken from 15 people 2 or 4 weeks after they had received a second dose of the Pfizer-BioNTech vaccine as part of a clinical trial.

The team found that the blood samples were able to neutralize the Brazil variant “roughly” as well as it could neutralize an earlier strain of the virus from January 2020.

The P.1 variant is suspected of fueling a resurgence of coronavirus cases in Brazil. It was found in 42% of samples in one survey carried out in Manaus and cases have since emerged in countries including the US, the UK and Japan.

The P.1 variant has mutations in common with the variant first identified in South Africa that are thought to make it more contagious and possibly able to evade immunity from vaccines – though this new study suggests the Pfizer-BioNTech vaccine may still be effective.

Pfizer previously reported findings that blood samples also neutralized variant B.1.351, first reported in South Africa. The study found neutralization was still “robust but lower.”

In February, Pfizer said that there is no evidence in real life that the South African variant escapes the protection offered by its vaccine but that they were working on developing a booster shot and an updated vaccine.
“Nevertheless, Pfizer and BioNTech are taking the necessary steps, making the right investments, and engaging in the appropriate conversations with regulators to be in a position to develop and seek authorization for an updated mRNA vaccine or booster once a strain that significantly reduces the protection from the vaccine is identified,” Pfizer said in a statement at the time.