Pfizer/BioNTech’s Vaccine Holds Up Against UK, South African Coronavirus Variants in In Vitro Studies

Researchers from Pfizer and the University of Texas Medical Branch have found that the Pfizer/BioNTech COVID-19 vaccine was still able to effectively neutralize key mutations in the highly contagious UK and South African coronavirus strains, offering hope that the prominent vaccine won’t need to be readjusted at this point.

The scientists engineered a trio of viruses — one with UK variant mutations, another with the South African mutations and the last with mutations common to both — and pitted them against a panel of human sera taken from 20 vaccinated participants who were in Pfizer’s late-stage trial.

The results from their in vitro neutralization studies showed that the three key mutations in the South African strain did have a small impact on the vaccine, but not enough to worry the drugmaker, who said the findings suggested that it would not need to revamp its vaccine for the variant.

“Neutralization against the virus with the three key mutations present in the South African variant was slightly lower when compared to neutralization of virus containing the other mutations that were evaluated. However, [we] believe the small differences in viral neutralization observed in these studies are unlikely to lead to a significant reduction in the effectiveness of the vaccine,” Pfizer said.

The study findings, which have not yet been peer-reviewed, were posted on the preprint server bioRxiv. The new research took a broader look at viral mutations than a previous study the drugmaker and the University of Texas Medical Branch reported earlier in the month, which was limited to a single mutation shared between the two variants (DID, Jan. 11).

Pfizer and BioNTech are currently evaluating the impact of the full set of mutations in the South African variant’s spike protein on their vaccine and said they are ready to make adjustments if a variant does prove capable of thwarting it.

Read the study findings here: bit.ly/3qYWAyh. — James Miessler