Even with the relief brought by the conditional approval of two coronavirus vaccines, a more virulent and contagious variant of the virus in the U.K. has emerged. 

Pfizer Inc. (NYSE:PFE), with its German partner BioNTech SE – ADR (NASDAQ:BNTX), and Moderna Inc (NASDAQ:MRNA) are the two companies that have received approval for emergency use of their respective investigational vaccines. 

Now the question is whether their vaccines would work against the new strain in the U.K. 

BioNTech Says It Could Tweak In 6 Weeks: BioNTech expressed confidence that it could produce a vaccine to take on new variants of SARS-CoV-2 within six weeks, the German company's CEO Ugur Sahin reportedly told the Financial Times.

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It would take two weeks to prove in a lab whether BNT162b2 – Pfizer-BioNTech's vaccine candidate would work effectively on the new strain, Sahin reportedly said.

Even if it doesn't, messenger RNA technology can be used to engineer a vaccine that completely mimics the new mutation, and a new vaccine could be made available within six weeks, Sahin was quoted as saying.

Pfizer reportedly told CNN that it is now generating data on whether blood samples from people vaccinated with BNT162b2 can neutralize the new strain from the U.K.

Moderna To Test Efficacy Against New Strain: The immunity provided by Moderna's investigational mRNA-1273 vaccine would offer protection against the new strain given the data generated to date, the CNN report said, citing a company statement.

"We will be performing additional tests in the coming weeks to confirm this expectation," the company said.

At last check, Pfizer shares were sliding 1.16% to $36.96, BioNTech shares were declining 4.67% to $101.49 and Moderna was plunging 7.96% to $127.29. 

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