Pfizer said on Wednesday that the booster dose of its COVID-19 vaccine may provide important protection for the new omicron variant, although the initial two doses of the vaccine appear to be significantly less effective.

Pfizer and its partner BioNTech said that although the protective effects of two doses of the vaccine may not be enough to prevent infection, laboratory tests have shown that one dose of booster increases people’s antiviral antibody levels by 25 times.

A blood sample collected one month after the booster immunization showed that the level of omicron neutralizing antibodies in people’s bodies was similar to the level of antibodies that proved protective against early mutations after two injections.

Scientists don’t yet know how big the real threat of omicron variants is. Currently, in the United States and other countries, most COVID-19 cases are caused by delta variants that are highly infectious.

However, the omicron variant discovered at the end of last month carries an unusually large number of mutations, and scientists are racing to understand how easily it spreads, whether it will cause more severe or milder disease than other coronavirus types—and to what extent it may be. On evasion protection from previous vaccinations.

The research results announced by Pfizer in the press release are preliminary and have not yet been scientifically reviewed. But they are the first study from a vaccine manufacturer that checks whether the booster doses that health authorities urge people to vaccinate actually have a significant impact.

Scientists speculate that the surge in antibodies from the third dose of the COVID-19 vaccine may be enough to offset any decline in effectiveness.

Pfizer and BioNTech are already working hard to develop an omicron-specific vaccine for emergencies.

Antibody levels can predict the effectiveness of vaccines against coronavirus infections, but they are only a layer of the immune system’s defenses. Pfizer stated that the two doses of the vaccine should still prevent serious diseases, because the omicron mutation does not seem to hinder one of the other defenses, namely T cells that fight the virus after the infection begins.

Pfizer CEO Albert Bourla said in a statement: “Although two doses of the vaccine may still protect against serious diseases caused by the Omicron strain, it is clear from these preliminary data , The third dose of vaccine can maximize protection.”

Pfizer’s statement had a direct impact on the US market. Futures pointing to a lower opening price reversed within a few seconds and turned firmly to positive as the Dow Jones index rose by nearly 200 points.