Despite the 95 percent effectiveness at preventing coronavirus infection after two doses of its vaccine, Pfizer is now seeing what a third dose might do.
The company announced [April 15] that a booster dose is being studied among people who received their first doses of the vaccine more than six months ago.
In an interview with NBC News’ Lester Holt, Pfizer CEO Albert Bourla said the hope is that a third dose will boost the immune response even higher, offering better protection against variants.
“We believe that the third dose,” Bourla said, “will raise the antibody response 10- to 20- fold.”
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Indeed, as SARS-CoV-2 changes, the vaccines may have to be tweaked… That’s not unlike how the flu shot changes from year to year, accounting for the strains most likely to infect people.
“Every year, you need to go to get your flu vaccine,” Bourla said. “It’s going to be the same with Covid. In a year, you will have to go and get your annual shot for Covid to be protected.”
Moderna, which makes a similar Covid-19 vaccine, announced [April 14] that it had also started studying the effects of adding a third dose to its regimen and has developed a version of the vaccine designed to target the variant from South Africa.