The COVID-19 vaccine from American drugmaker Pfizer and its German partner BioNTech appeared to lose only a small bit of effectiveness against an engineered virus similar to the new variant found in South Africa, according to a laboratory study.
The study by Pfizer and scientists from the University of Texas Medical Branch (UTMB), showed a less than two-fold reduction in antibody concentration levels, indicating the vaccine would likely still be effective in neutralizing a virus with the so-called E484K and N501Y mutations found in the South African variant.
The study was conducted on blood taken from people who had been given the vaccine. Its findings are limited, because it does not look at the full set of mutations found in the new South African variant.
The scientists are currently engineering a virus with the full set of mutations and expect to have results from that in around two weeks, according to Pei-Yong Shi, an author of the study and a professor at UTMB.
The results are more encouraging than another non-peer reviewed study from scientists at Columbia University published earlier which used a slightly different method and showed antibodies generated by the shots were significantly less effective against the South Africa variant.
One possible reason for the difference could be that the Pfizer findings are based on an engineered coronavirus, and the Columbia study used a different type of virus, Mr. Shi said.
The study also showed even better results against several key mutations from the highly transmissible UK variant of the virus. Mr. Shi said they were also working on an engineered virus with the full set of mutations from that variant as well.