• Pfizer and BioNTech have released new data on how their vaccine works against Omicron variant.
• They claimed that Omicron antibodies were less effective in two doses than for other variants.
• They said that a third dose of the drug significantly increased the immune response, which is a positive sign.

Pfizer and BioNTech announced Wednesday that their vaccine against coronavirus was effective against Omicron variants under a three-dose regimen, but that only two doses produced a lower response.

In a press release, the companies updated the public about lab tests to evaluate the effectiveness of the vaccine against Omicron (a fast-spreading strain discovered last month).

The results of the tests showed that Omicron protective antibodies were higher after three than two doses. Although it provides some indications of the effectiveness of vaccines against the virus, the early data is not perfect.

Scientists around the globe and companies are working together to understand how Omicron works and what vaccines can be used against it. Because of the large number of mutations, this variant is causing concern.

Albert Bourla, CEO of Pfizer, stated in the news release that even though two doses of vaccine might still provide protection against severe Omicron strain-related disease, preliminary data show that the third dose of the vaccine provides greater protection.

These are the main findings:

• Two doses of Pfizer's vaccine resulted in 25 percent fewer neutralizing antibodies to Omicron than the original coronavirus strain.
• One month later, Omicron antibodies were back at the same levels as after the second dose.
• Other immune cells, such as CD8+ T cells and those that don't depend upon antibodies to kill the virus can still recognize about 80% of Omicron targets.
• After a third dose, the level of CD8+ cells is higher.

Early evidence suggests that the Omicron variant is easier to catch than the Delta variant. However, it could lead to less severe infections.

Pfizer is currently working on an improved vaccine that targets the Omicron variant.