Pfizer, Moderna urge calm as they launch tests of vaccines against mutated COVID-19

After a mutated, fast-spreading variant of COVID-19 in the U.K. disrupted global travel over the weekend, a troubling question emerged: Will the new vaccines from Pfizer and Moderna work against this scary new strain of the virus?

Now the two companies, along with Pfizer’s COVID-19 partner BioNTech, are rushing to calm a nervous public. They’re launching new studies designed to prove their mRNA-based shots will fend off the new coronavirus strain, while simultaneously expressing confidence this new vaccine technology is ideal for protecting against rapidly mutating viruses.

Pfizer and BioNTech have tested their vaccine “for its ability to neutralize multiple mutant strains. To date, we have found consistent coverage of all the strains tested,” they said in a statement. The companies are now collecting data from people who have received the shot to determine how well they “may be able to neutralize the new strain from the U.K.,” Pfizer added.

Moderna did not immediately respond to a request for comment but said in a statement provided to other media outlets that it expects “that the Moderna vaccine-induced immunity would be protective against the variants recently described in the U.K.,” and that it “will be performing additional tests in the coming weeks to confirm this expectation.”

Pfizer pointed out that when SARS-CoV-2, the virus that causes COVID-19, first emerged a year ago, it was clear there was more than one strain of it, and that it was mutating as it spread. SARS-CoV-2 is an RNA virus, and as such, it has “exceptionally high [mutation] rates” because the enzymes it uses for replication are “prone to errors when making new virus copies,” the company said.

“One of the reasons Pfizer and BioNTech chose to utilize a mRNA platform is because of the potential for the flexibility of the technology in comparison to traditional vaccine technologies,” including the ability to change the RNA sequence in the vaccine, should a strain emerge that’s not covered by the current shot,” Pfizer added.

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The concern about the aggressive new coronavirus strain is the latest headache facing Pfizer during what has been anything but a smooth rollout of its COVID-19 vaccine. Last week, Health and Human Services Secretary Alex Azar said during a press conference that Pfizer was facing “various challenges” in manufacturing the vaccine. CEO Albert Bourla said in a TV interview that the company’s vaccine manufacturing sites were “running at critical supply limitations.”  

Pfizer issued a long statement in response, saying it was “not having any production issues,” and that “no shipments containing the vaccine are on hold or delayed.” It added that it has “millions more doses sitting in our warehouse but, as of now, we have not received any shipment instructions for additional doses.”

On Saturday, Operation Warp Speed co-leader Gen. Gustave Perna apologized for logistical hiccups that resulted in 14 states getting fewer doses than expected of Pfizer’s vaccine.

Meanwhile, Moderna won emergency use authorization for its COVID-19 vaccine Friday night and said it expected to deliver 20 million doses in the U.S. by the end of the year.

RELATED: With Pfizer shot spoken for, U.S. snaps up 100M more Moderna COVID-19 vaccine doses

Earlier this month, the U.S. government exercised its option to buy additional doses of the Moderna vaccine, laying out $1.68 billion to double its order to 200 million doses. The additional shots will be delivered in the second quarter of 2021. The government paid $1.525 billion to Moderna for the first 100 million doses it ordered.

Pfizer’s $1.95 billion deal with the U.S. covered 100 million doses, plus an option for more. Pfizer is negotiating with the government to supply more of the vaccine, but an expansion of the original deal has yet to be announced.