Pfizer Covid-19 vaccine works against mutations found in UK and South Africa, lab study finds

Researchers have rushed to assess whether Covid-19 vaccines and drugs will still work against new variants, as governments roll out injections they hope will allow schools, businesses and other facilities to reopen .

Pfizer’s results are consistent with other preliminary results reported in recent weeks by several research groups examining the effectiveness of available vaccines against the new variants.

The research is however still preliminary. Pfizer’s study was conducted in a lab and only tested a subset of mutations found in the variants, but not the variants themselves. In addition, the researchers did not assess whether their results were statistically significant.

Still, these and other results suggest that the impact of variants on injections will be “relatively modest, which is good news for vaccines,” said Jason McLellan, a structural biologist at the University of Texas at Austin who studied how coronavirus proteins interact with antibodies and was not involved in the Pfizer study.

Pfizer said that “the results do not indicate the need for a new vaccine to treat emerging variants.” However, the company said that it and its partner BioNTech SE BNTX -0.30%

were ready to respond to a vaccine-resistant version of the virus.

The Pfizer-BioNTech vaccine uses a new technology called messenger RNA, named after molecular couriers of genetic instructions, that allows developers to make changes to their vaccines faster than more traditional techniques. The other vaccine authorized in the United States, derived from Moderna biotechnology Inc.,

also uses mRNA technology.

A recent preliminary study by Moderna, in collaboration with scientists from the National Institutes of Health in the United States, showed that the antibodies generated by its vaccine were less effective at binding the mutated spike proteins of the South African variant. The researchers did not find a difference for the peak proteins of the British variant. The coronavirus uses its advanced proteins, which stud its surface, to penetrate and infect cells. Proteins are key targets for antibodies.

As a precaution, the company said it was developing a recall for the South African variant.

The new Pfizer study found that the antibodies generated by its vaccine were slightly better at binding to versions of the virus that had some of the mutations found in the UK variant.

This could be because scientists tested their variant-type viruses in the UK against a variant that did not have an older but key mutation that increases transmissibility, but makes the virus more susceptible to antibodies, the virus said. Dr McLellan.

The gold standard would test antibodies against the variants themselves, he and others have said, to understand how their unique constellation of mutations might affect a vaccine’s natural immunity or protection.

These studies are ongoing in laboratories around the world.

Pfizer researchers, who worked with scientists in the University of Texas medical branch, did not perform statistical significance tests, a key way for scientists to assess whether their results were due to chance and have real-world importance, another significant limitation, scientists not involved in the study said.

Rafael Casellas, a molecular immunologist at NIH, said it was important to continue monitoring the progress of the coronavirus to assess whether vaccines and other therapies will need to be updated or whether booster injections will be needed. “We cannot take this virus lightly,” he says. “We just don’t have enough information, so we have to be careful.”

Write to Daniela Hernandez at [email protected]