Pfizer and BioNTech said their FDA request is based on results of a study, conducted by the two companies, which has not been published or peer-reviewed.By Megan Redshaw
Pfizer and BioNTech on Tuesday asked the U.S. Food and Drug Administration (FDA) to authorize a third dose of their COVID vaccine for all people 18 and older, even though advisory panels to the FDA and Centers for Disease Control and Prevention (CDC) in September overwhelmingly rejected a similar request.
The companies said the study of more than 10,000 volunteers showed vaccine efficacy against symptomatic infection of 95% or greater for people receiving the booster.
According to the Associated Press, a median of 11 months after receiving their last Pfizer vaccine dose, trial participants were given either a third booster dose or a placebo shot. Researchers tracked any infections that occurred at least a week later.
So far, five cases of symptomatic COVID occurred among booster recipients compared to 109 cases in the placebo group.
Pfizer did not disclose how many participants experienced asymptomatic infection, or whether the clinical trial included individuals with natural immunity acquired from previous SARS-CoV-2 infection — as did Pfizer’s clinical trial for 5 to 11 years olds.