Pfizer vaccine only slightly less effective against major mutations in South Africa – study

NEW YORK (Reuters) – The COVID-19 vaccine from Pfizer Inc and BioNTech has lost only a little effectiveness against a virus modified with three major mutations of the new coronavirus variant found in South Africa, according to a laboratory study conducted by the US pharmacist.

The study by Pfizer and scientists at the University of Texas Medical Branch (UTMB), which has not yet been peer-reviewed, showed a less than two-fold reduction in antibody titer levels, indicating that the vaccine would likely be effective in neutralizing a virus with the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 here was conducted with blood drawn from people who received the vaccine. His findings are limited because he does not examine the full set of mutations found in the new South African variant.

While these findings do not indicate the need for a new vaccine to deal with emerging variants, Pfizer and BioNTech are prepared to answer whether a variant of SARS-CoV-2 shows evidence of escape from immunity by the COVID-19 vaccine, said companies .

Scientists are currently developing a virus with the full set of mutations and hope to have results in about two weeks, according to Pei-Yong Shi, study author and professor at UTMB.

The results are more encouraging than another study not reviewed by Columbia University scientists on 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 may be that Pfizer’s findings are based on a modified coronavirus, and the Columbia study used a pseudovirus based on the vesicular stomatitis virus, a different type of virus, said UTMB’s Shi. He said he believed the pseudovirus discovery should be validated using the real virus.

The study also showed even better results against several major mutations of the highly transmissible British variant of the virus. Shi said they were also working on a modified virus with the full set of mutations for that variant.