results, comes as the company is preparing within days to formally ask U.S. regulators to allow emergency use of the vaccine.Pfizer initially had estimated its vaccine, developed with German partner BioNTech, was more than 90% effective after 94 infections had been counted.
With Wednesday’s announcement, the company now has accumulated 170 infections in the study -- and said only eight of them occurred in volunteers who got the actual vaccine rather than a dummy shot.
One of those eight developed severe disease, the company said. The company has not yet released detailed data on its study, and results have not been analyzed by independent experts.