A third dose of Pfizer’s COVID-19 vaccine neutralizes the Omicron variant of the coronavirus that’s caused global alarm over the past two weeks, the drugmaker said Wednesday.
Pfizer and its German partner BioNTech said that preliminary results of a laboratory study show a booster dose of the vaccine “provides a similar level of neutralizing antibodies to Omicron as is observed after two doses against” the original virus “and other variants that emerged before Omicron.”
The companies did not release the full preliminary data that led to their findings, opting instead to only issue a press release. That means the data has not been reviewed by any impartial third-party scientists and it’s unclear when more complete data will be available.
“Our preliminary, first dataset indicate that a third dose could still offer a sufficient level of protection from disease of any severity caused by the Omicron variant,” Dr. Ugur Sahin, CEO and co-founder of BioNTech, said in a statement.
“Broad vaccination and booster campaigns around the world could help us to better protect people everywhere and to get through the winter season,” he added.
Among those who had received just two doses of the shot, the companies said they observed a “more than a 25-fold reduction in neutralization titers against the Omicron variant compared to” the original strain, referred to as the “wild-type.”
Pfizer said this finding suggests “that two doses of [Pfizer’s vaccine] may not be sufficient to protect against infection with the Omicron variant.”
“However, as the vast majority of epitopes targeted by vaccine-induced T cells are not affected by the mutations in Omicron, the companies believe that vaccinated individuals may still be protected against severe forms of the disease and are closely monitoring real world effectiveness against Omicron, globally,” the companies added.
“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine,” Pfizer CEO Albert Bourla said in a statement.
“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.”
Pfizer and BioNTech started to develop an Omicron-specific COVID-19 vaccine on Nov. 25, the companies said, and will continue to develop it in case it’s needed. First batches could be delivered within 100 days, the companies said, pending regulatory approval.
“The companies have high confidence that if needed they can deliver an Omicron-based vaccine in March 2022,” Pfizer and BioNTech said.
BioNTech’s Sahin said in a statement that they believe an Omicron-specific vaccine would provide “prolonged protection compared to the current vaccine.”
Shares of Pfizer rose less than 1 percent in premarket trading to about $52 per share.