Pfizer Says Its COVID Vaccine Is Still 91% Effective After Six Months
By Bill Galluccio
April 1, 2021
Pfizer and BioNTech announced that their coronavirus vaccine remains more than 91% effective after six months and provides protection against the South African variant of COVID-19.
The two companies said the study involved around 46,000 people. Some of the volunteers were given the vaccine, while others were given a placebo. While 927 of the volunteers developed symptomatic cases of COVID-19, most of them were in the placebo group.
"From the 927 confirmed symptomatic cases of COVID-19 in the trial, 850 cases of COVID-19 were in the placebo group, and 77 cases were in the BNT162b2 group, corresponding to vaccine efficacy of 91.3%," the companies said in a joint statement.
They added that there were 21 cases of severe infection in the study participants, but just one of those cases occurred in somebody who received the vaccine.
"It is an important step to further confirm the strong efficacy and good safety data we have seen so far," said Ugur Sahin, CEO, and co-founder of BioNTech. "These data also provide the first clinical results that a vaccine can effectively protect against currently circulating variants, a critical factor to reach herd immunity and end this pandemic for the global population."
According to the Centers for Disease Control and Prevention, nearly 77 million doses of Pfizer's vaccine have been administered in the U.S. as of March 31.
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