Existing coronavirus vaccines are likely to be less effective against the emerging omicron variant, Moderna CEO Stéphane Bancel predicted on Tuesday.
"There is no world, I think, where [the effectiveness] is the same level ... we had with [the] Delta [variant]," he told the Financial Times, while noting that that the drugmaker is still testing its vaccine on omicron.
"I think it's going to be a material drop," Bancel added. "I just don't know how much because we need to wait for the data. But all the scientists I've talked to . . . are like, 'This is not going to be good.'"
As more cases of Omicron emerge in Asia, Europe and North America, the race is on for drugmakers to produce vaccines capable of fighting the omicron variant. Officials with Moderna, Johnson & Johnson and Pfizer said last week they have started trials of their vaccines against omicron, although results will likely take weeks.
Health authorities say Omicron carries an "unprecedented number" of mutations, even compared to the fast-spreading Delta variant, which currently makes up virtually all U.S. cases. Some of these mutations might make the Omicron variant more transmissible, as well as resistant to vaccines, health authorities say. The World Health Organization, or WHO, designated Omicron a "variant of concern" last week, noting in a statement that early evidence "suggests an increased risk of reinfection."
Although scientists are working as fast as possible, it will take months for Moderna to produce and ship a new vaccine formula for the public, Bancel told CNBC on Monday.
Despite the Moderna executive's warning, epidemiologists caution that it is too early to say how dangerous Omicron could be. To that end, the CEO of another vaccine maker said Tuesday that infections caused by the new variant likely will not cause severe illness for vaccinated people.
"Our message is: Don't freak out, the plan remains the same: Speed up the administration of a third booster shot," BioNTech co-founder Ugur Sahin, who helped invent Pfizer's COVID-19 vaccine, told the Wall Street Journal.
Dutch health authorities announced on Tuesday that they found the Omicron variant in cases dating back as long as 11 days, indicating that it was already spreading in western Europe before the first cases were identified in southern Africa. Since then, cases have been detected in Australia, Belgium, Canada, Israel, Italy, Japan, Sweden and other countries.
No Omicron cases have been confirmed in the U.S. But Dr. Scott Gottlieb, former head of the Food and Drug Administration, said Sunday in an interview with CBS News' "Face the Nation" that the new variant is "almost definitely" already here.
Dr. Anthony Fauci, chief medical adviser to President Joe Biden, on Saturday also said he wouldn't be surprised if Omicron has already arrived in the U.S. Mr. Biden urged Americans this week not to panic about Omicron as researchers seek to learn more about about the new variant.
"Sooner or later, we're going to see cases of this new variant here in the United States," the president said Monday. "We'll have to face this new threat, just as we faced those that have come before it."