(CNN) – The companies said in a statement Wednesday that preliminary laboratory studies show that two doses of the Pfizer/BioNTech vaccine may not provide adequate protection against the omicron variant of the coronavirus, but that three doses may neutralize it.
Initial laboratory studies used serum from people who received two to three doses of the Pfizer/BioNTech vaccine against COVID-19. Sera were collected from subjects three weeks after the second dose, or a month after the third dose.
Samples of subjects who received two doses of the covid-19 vaccine experienced, on average, a more than 25-fold decrease in neutralizing ability against the omicron variant compared to the previous virus, “suggesting that two doses of BNT162b2 may not be sufficient protection against infection with the omicron variant” .
The companies said two doses could provide protection against serious disease.
“Although two doses of the vaccine still provide protection against severe disease caused by the omicron variant, it is clear from these preliminary data that protection is improved with a third dose of our vaccine,” said Pfizer President and CEO Albert Borla. in the current situation.
“Ensuring that as many people as possible are fully vaccinated with the first two series of doses and booster doses is the best course of action to prevent the spread of COVID-19,” Burla added.
Pfizer and BioNTech are continuing to develop a variant vaccine for Omicron and say it will be available in March, if needed.
The data released on Wednesday has not been reviewed or published.
South African researchers on Tuesday released a preliminary study showing that the Omicron type of coronavirus partially escapes the protection offered by the Pfizer vaccine, but people who were previously infected and then vaccinated are likely to be well protected.
Alex Segal of the Africa Health Research Institute in Durban, who led the study, told CNN that reinforcers may also protect people.
“My impression is that if you get a booster dose, you’re protected, especially from serious diseases,” Segal said.