|Articles|January 8, 2021

Pfizer COVID-19 Vaccine Shows Efficacy Versus New Variants

In vitro data suggest the more transmissible mutations of the virus are nonetheless prevented by the mRNA vaccine.

Yet-to-be reviewed in vitro data from Pfizer and the University of Texas Medical Branch indicate coronavirus 2019 (COVID-19) vaccine BNT162b2 is effective in preventing the pandemic virus’ highly transmissible mutated variants currently spreading globally.

In a promising report from early Friday morning, the vaccine developers and Texas investigators stated their pending study of the mRNA vaccine versus the N501Y spike protein mutation of SARS-CoV-2, initially observed in Britain and Africa, would alleviate worry surrounding the more infectious form of the virus at a time when global vaccination has already begun.

The assessment, per Reuters, involved the analysis of vaccinated persons’ blood against 16 different SARS-CoV-2 mutations currently in circulation around the world.

Though it is a promising start to clinical review for one of the first COVID-19 vaccines being distributed, as one Pfizer expert put it, there’s no guarantee “the 17th” mutation won’t best the prophylaxis.

Similar tests are being planned to establish vaccine efficacy against other mutations observed in the British and South African variants, with results pending in the coming weeks. At the same time, other vaccine developers including Moderna, AstraZeneca, and CureVac have stated intent to test their products versus the variants.

The companies have similarly expressed hope their vaccines will remain efficacious. Particularly regarding mRNA vaccines—from both Pfizer and Moderna—developers have the capability to quickly adjust the synthetic messenger RNA technology to respond to new mutations.

Last week, the World Health Organization (WHO) shared a risk assessment and guidance report on a quartet of circulating SARS-CoV-2 variants, including the N501Y mutation.

Though early assessment implies the UK and South African variants do not cause change in clinical presentation or severity, their potential for higher case incidence could lead to increased COVID-19 related hospitalizations, and therefore, deaths. As such, WHO warned more intensive public health response may be necessary to control variant transmission, pending research.

WHO also advised countries increase routine systematic sequencing of SARS-CoV-2 viruses, when possible, to better monitor variant emergence.

“While mutations of SARS-CoV-2 are expected, it is important to continue to monitor the public health implications of new virus variants,” they wrote. “Any increased in transmissibility associated with SARS-CoV-2 variants could make control more difficult.”


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