Pfizer vaccine is only slightly less effective against major South African mutations: study

Pfizer Inc and BioNTech’s COVID-19 vaccine appeared to lose only a small amount of effectiveness against a virus made with three key mutations of the novel coronavirus variant found in South Africa, according to a laboratory study conducted by the US maker of drugs.

The study by Pfizer and scientists at the University of Texas Medical Branch (UTMB), which has not yet been peer reviewed, showed less than twice a reduction in levels of antibody titer, indicating that the vaccine would likely be effective in neutralizing a virus. with the so-called E484K and N501Y mutations found in the South African variant.

The study was carried out on blood taken from people who had received the vaccine. Its results are limited because it does not look at the full set of mutations found in the new South African variant.

Although these results do not indicate the need for a new vaccine to treat emerging variants, Pfizer and BioNTech are ready to respond if a variant of SARS-CoV-2 shows evidence of evading immunity by the vaccine. COVID-19, the companies said. .

According to Pei-Yong Shi, author of the study and professor at UTMB, scientists are currently designing a virus with the full set of mutations and expect to have results in about two weeks.

The results are more encouraging than another unpaired study conducted by scientists at Columbia University earlier Wednesday, which used a slightly different method and showed that the antibodies generated by the injections were significantly less effective against the South African variant.

One possible reason for the difference could be that Pfizer’s results are based on a modified coronavirus, and the Columbia study used a pseudovirus based on vesicular stomatitis virus, a different type of virus, said Shi of the ‘UTMB. He said he believed the pseudovirus discovery should be validated using the real virus.

The study also showed even better results against several key mutations in the highly transmissible British variant of the virus. Shi said they are also working on a virus designed with the full set of mutations in this variant.