Here's How Pfizer's Vaccine Fares Against Omicron

Two doses of the Pfizer/BioNTech coronavirus vaccine may be enough to prevent serious illness with the omicron variant, but may not be enough to prevent an infection, the companies said Wednesday. However, "preliminary laboratory studies demonstrate that three doses of the Pfizer-BioNTech COVID-19 vaccine neutralize the omicron variant," according to a press release, which comes on the heels of a preprint study that predicted such results. Indeed, "a third dose provides a similar level of neutralizing antibodies to omicron as is observed after two doses against wild-type and other variants that emerged before omicron."

Samples from people with two doses of the vaccine known as Comirnaty showed a more than 25-fold reduction in neutralization ability against omicron compared to earlier versions of the virus, "indicating that two doses of BNT162b2 may not be sufficient to protect against infection with the omicron variant," the release reads, per CNN. But the data—not yet peer-reviewed or published—indicate a third dose increases neutralization ability against the omicron variant by 25-fold compared to two doses. In other words, "a third dose could still offer a sufficient level of protection from disease of any severity caused by the omicron variant," said BioNTech CEO Dr. Ugur Sahin.

"Ensuring as many people as possible are fully vaccinated with the first two dose series and a booster remains the best course of action to prevent the spread of COVID-19," added Pfizer CEO Albert Bourla. Still, the companies continue to develop an omicron-specific vaccine just in case. CNN reports it will be available in March. With the news, shares of Pfizer climbed 1% in premarket trading Wednesday, per Reuters. "This is really the first positive news in terms of the potential effectiveness of existing vaccines," Rick Meckler of New Jersey's Cherry Lane Investments told the outlet. Meanwhile, the World Health Organization said hospitalizations were likely to rise due to the spread of omicron, now reported in 57 countries. (More Comirnaty stories.)