Vaccine partners Pfizer (NYSE:PFE) and BioNTech (NASDAQ:BNTX) released information today that provides new evidence that their COVID-19 vaccine is effective against the B.1.1.7 variant that was initially detected in the United Kingdom and is believed to be more contagious than the original strain of the coronavirus.

Depiction of colorful coronaviruses.

Image source: Getty Images.

Pfizer and BioNTech conducted a laboratory study in which blood serum from trial subjects who had received the companies' BNT162b2 vaccine was exposed to pseudoviruses bearing either the spike protein of the original Wuhan strain or that of the B.1.1.7 variant. Pseudoviruses are synthesized in a laboratory to mimic true viruses but are safer to handle because they can only replicate once.

In the study, investigators tested sera from 16 trial subjects -- eight from adults between 18 and 55 years old and eight from older subjects. The test showed no biologically significant difference in the neutralization of the variant compared with the original strain. The authors of the study concluded that the observed neutralization "makes it very unlikely that the UK variant viruses will escape BNT162b2-mediated protection."

The issue won't be completely settled until there is more data from vaccinated patients exposed to the real virus variant. But BioNTech stock has been under pressure over worry about the U.K. variant, so the data released today is good news for investors in two healthcare companies in the forefront of the fight against COVID-19.

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