Pfizer says it is about to seek U.S. authorization for a third dose of its COVID-19 vaccine.
The company said Thursday that another shot could dramatically boost immunity and maybe help ward off the latest worrisome coronavirus mutant.
Research from multiple countries shows the widely used COVID-19 vaccines offer strong protection against the highly contagious delta variant.
Two doses of most vaccines are critical to developing high levels of virus-fighting antibodies.
But those antibodies naturally wane.
So studies also are underway to tell if and when boosters might be needed.
Pfizer says early data from a company trial suggests people's antibody levels jump after they get a third dose.
In an interview with the Associated Press, Pfizer’s Dr. Mikael Dolsten said the level of antibodies in people jumped "five- to 10-fold after a third dose."
According to the AP, Pfizer plans to ask the Food and Drug Administration in August for a third dose emergency authorization.
Dolsten said that data from Britain and Israel showed the Pfizer vaccine neutralizing "the delta variant very well," the AP reported.
In a joint statement, which was released Thursday evening, the Food and Drug Administration and the U.S. Centers for Disease Control and Prevention said that booster shots were not needed at this time.
"Americans who have been fully vaccinated do not need a booster shot at this time. FDA, CDC, and NIH are engaged in a science-based, rigorous process to consider whether or when a booster might be necessary," the statement read, which was obtained by Axios and CNN. "This process takes into account laboratory data, clinical trial data, and cohort data – which can include data from specific pharmaceutical companies but does not rely on those data exclusively. We continue to review any new data as it becomes available and will keep the public informed. We are prepared for booster doses if and when the science demonstrates that they are needed."