- REUTERS - Feb 17, 2021 -
(This February 17 story corrects headline and first paragraph to show the reduction was in the protective antibodies elicited by the vaccine, not the protection of the vaccine overall)
(Reuters) - A laboratory study suggests that the South African variant of the coronavirus may reduce protective antibodies elicited by the Pfizer Inc/BioNTech SE vaccine by two-thirds, and it is not clear if the shot will be effective against the mutation, the companies said on Wednesday.
The study found the vaccine was still able to neutralize the virus and there is not yet evidence from trials in people that the variant reduces vaccine protection, the companies said.
Still, they are making investments and talking to regulators about developing an updated version of their mRNA vaccine or a booster shot, if needed.
For the study, scientists from the companies and the University of Texas Medical Branch (UTMB) developed an engineered virus that contained the same mutations carried on the spike portion of the highly contagious coronavirus variant first discovered in South Africa, known as B.1.351. The spike, used by the virus to enter human cells, is the primary target of many COVID-19 vaccines.
Researchers tested the engineered virus against blood taken from people who had been given the vaccine, and found a two- thirds reduction in the level of neutralizing antibodies compared with its effect on the most common version of the virus prevalent in U.S. trials.