Pfizer-BioNTech COVID-19 Vaccine Effectively Neutralizes Highly Transmissible SARS-CoV-2 Mutations, Finds New Study

An in vitro study has shown that the antibodies from people who have received the COVID-19 vaccine from Pfizer Inc. (New York, NY, USA) and Biopharmaceutical New Technologies (BioNTech Mainz, Germany) effectively neutralize SARS-CoV-2 with a key mutation that is also found in two highly transmissible strains.

The rapidly spreading variants of SARS-CoV-2 which have been reported initially in the UK and South Africa have multiple mutations in their spike or S glycoproteins, which are key targets of virus neutralizing antibodies. Though these two rapidly spreading viruses are different, they share the N501Y mutation, which is located in the receptor binding site of the spike protein and results in the virus’s spike protein binding more tightly to its receptor. It has been shown to infect mice more efficiently.


An in vitro study was conducted by Pfizer and the University of Texas Medical Branch (UTMB; Galveston, TX, USA) to determine if sera of people who had received the Pfizer-BioNTech COVID-19 vaccine could neutralize SARS-CoV-2 with the N501Y mutation. A virus with this substitution was generated in UTMB’s laboratory. The sera of 20 participants from the previously reported Phase 3 trial neutralized the virus with the mutation as well as without the mutation.

While the virus tested in this experiment did not include the full set of spike mutations found on the rapidly spreading strains in the UK or South Africa, neutralization of virus with the N501Y mutation by the Pfizer- BioNTech vaccine-elicited human sera is consistent with preserved neutralization of a panel of 15 pseudoviruses bearing spikes with other mutations found in circulating SARS-CoV-2 strains. This indicates that the key N501Y mutation, which is found in the emerging UK and South Africa variants, does not create resistance to the Pfizer-BioNTech vaccine induced immune responses.

Pfizer, BioNTech, and UTMB have found these early, in vitro study findings to be encouraging. Further data are needed to monitor the Pfizer-BioNTech COVID-19 vaccine’s effectiveness in preventing COVID-19 caused by new virus variants. If the virus mutates such that an update to the vaccine is required to continue to confer protection against COVID-19, Pfizer believes that the flexibility of BioNTech’s proprietary mRNA vaccine platform is well suited to enable an adjustment to the vaccine.

Related Links:
Pfizer Inc.
Biopharmaceutical New Technologies
University of Texas Medical Branch (UTMB)