Pfizer to seek FDA authorization of booster shot

Pfizer Inc plans to ask U.S. regulators to authorize a booster dose of its COVID-19 vaccine within the next month, the drugmaker's top scientist said on Thursday, based on evidence of greater risk of reinfection six months after inoculation and the spread of the highly contagious Delta variant.

Gloria Tso reports.

Pfizer said on Thursday that it will ask U.S. regulators to authorize a third booster shot of its COVID-19 vaccine within the next month, based on evidence of greater risk of reinfection six months after inoculation and the fast-spreading Delta variant.

Pfizer's chief scientific officer, Mikael Dolsten, said a recently reported dip in the vaccine's effectiveness in Israel was mostly due to infections in people who had been vaccinated in January or February.

Pfizer did not release the full set of Israeli data on Thursday, but said it would be published soon.

But Pfizer stressed that data from Israel and Britain suggests that even with waning antibody levels, the vaccine remains around 95% effective against severe disease.

Dolsten said that early data from the company's own studies shows that a third booster dose generates antibody levels that are five to 10-fold higher than after the second dose, suggesting that a third dose will offer promising protection.

He said that multiple countries in Europe and elsewhere have already approached Pfizer to discuss booster doses, and that some may begin administering them before a potential U.S. authorization.

Meanwhile, U.S. regulators said late on Thursday that Americans who have been fully vaccinated do not need a booster COVID-19 shot at this time, writing quote:"We are prepared for booster doses if and when the science demonstrates that they are needed."