Pfizer to seek OK for 3rd, booster shot, to extend protection

Pfizer to ask FDA to authorize booster dose of COVID vaccine as Delta variant spreads Pfizer Inc (PFE.N) 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 due to the spread of the highly contagious Delta variant. Michael Erman Reuters

NEW YORK, July 8 (Reuters) - Pfizer Inc (PFE.N) 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 due to the spread of the highly contagious Delta variant.

Pfizer Chief Scientific Officer Mikael Dolsten said the 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. The country's health ministry said vaccine effectiveness in preventing both infection and symptomatic disease fell to 64% in June. read more

"The Pfizer vaccine is highly active against the Delta variant," Dolsten said in an interview. But after six months, he said, "there likely is the risk of reinfection as antibodies, as predicted, wane."

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

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

The vaccine, developed with German partner BioNTech SE , showed 95% efficacy in preventing symptomatic COVID-19 in a clinical trial the companies ran last year.

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. ...