Pfizer CEO Albert Bourla speaks at a press conference after a visit to oversee the production of the Pfizer-BioNtech COVID-19 vaccine at the plant of US pharmaceutical company Pfizer in Puurs, Belgium, on April 23, 2021.
Jean Thys | Swimming pool | Reuters
Pfizer CEO Albert Bourla said on Monday that two doses of the company’s vaccine may not offer strong protection against infection with the omicron Covid variant, and that the original injections have also lost some of their effectiveness for prevent hospitalization.
Bourla, in an interview with the JP Morgan Healthcare Conference, stressed the importance of a third blow to strengthen people’s protection against omicron.
“The two doses, they are not enough for omicron,” Bourla said. “The third dose of the current vaccine offers fairly good protection against death and decent protection against hospitalizations.”
Bourla said the omicron is a more difficult target than previous variants. Omicron, which has dozens of mutations, may escape some of the protection offered by Pfizer’s original two injections.
“We saw very clearly with a second dose that the first thing we lost was protection against infection,” Bourla said. “But two months later, what was once very strong in hospitalization has also gone down. And I think that’s what everyone worries about.”
Real data from the UK has shown that two doses of the vaccine are 52% effective in preventing hospitalization 25 weeks after receiving the second injection, according to data from the UK Health Security Agency.
According to UK data, two doses of Pfizer or Moderna vaccines are only about 10% effective in preventing omicron infection 20 weeks after the second dose.
A booster dose, on the other hand, is up to 75% effective in preventing symptomatic infection and 88% effective in preventing hospitalization, according to the data.
However, Bourla said it is not clear how long a booster dose will provide protection against Covid. The UK Health Security Agency has also found that the boosters are only 40-50% effective against infection 10 weeks after receiving the vaccine.
“The question mark is how long this protection lasts with the third dose,” Bourla said.
The United States Centers for Disease Control and Prevention now recommends that some people with weakened immune systems receive four injections, three primary doses and a booster. Israel has rolled out the fourth doses of Pfizer for people over 60. Israel found that the fourth doses increased the protective antibodies by a factor of five.
Bourla told CNBC earlier Monday that Pfizer would have a vaccine that specifically targets omicron ready in March, although he said it was not clear whether or not it would be needed.
Bourla also told CNBC that more testing needed to be done to determine whether or not a fourth dose was needed.