Pfizer says that more interim results from its ongoing coronavirus vaccine study suggest the shots are 95% effective and that the vaccine protects older people most at risk of dying from COVID-19.
Wednesday’s announcement from Pfizer and its German partner BioNTech, just a week after revealing the first promising preliminary results, comes as the team is preparing within days to formally ask U.S. regulators to allow emergency use of the vaccine.
They also have begun “rolling submissions” for the vaccine with regulators in Europe, the U.K. and Canada and soon will add this new data.
Pfizer and BioNTech had initially estimated the vaccine was more than 90% effective after 94 infections had been counted in a study that included 44,000 people. With the new 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.
“This is an extraordinarily strong protection,” Dr. Ugur Sahin, BioNTech’s CEO and co-founder, told The Associated Press.
The companies have not yet released detailed data on its study, and results have not been analyzed by independent experts.
They said the vaccine was more than 94% effective in adults over age 65, though it is not clear exactly how that was determined with only eight infections in the vaccinated group to analyze and no breakdown provided of those people’s ages.
But Sahin said there were enough older adults enrolled in the study and among the placebo recipients who became infected that he is confident “this vaccine appears to work in the higher-risk population.”
Earlier this week Moderna, Inc. announced that its experimental vaccine appears to be 94.5% effective after an interim analysis of its late-stage study.
Pfizer and BioNTech also say now have the required data on the vaccine’s safety needed to seek emergency authorization from the Food and Drug Administration.
The companies didn’t disclose safety details but said no serious vaccine side effects have been reported, with the most common problem being fatigue after the second vaccine dose, affecting about 4% of participants.
The study has enrolled nearly 44,000 people in the U.S. and five other countries. The trial will continue to collect safety and efficacy data on volunteers for two more years.
Pfizer and BioNTech said they expect to produce up to 50 million vaccine doses globally in 2020 and up to 1.3 billion doses in 2021.
U.S. officials have said they hope to have about 20 million vaccine doses each from Moderna and Pfizer available for distribution in late December. The first shots are expected to be offered to vulnerable groups like medical and nursing home workers, and people with serious health conditions.
AP writers Frank Jordans and Lauran Neergaard contributed to this report.