A vial of the Pfizer/BioNTech COVID-19 vaccine is seen ahead of being administered at the Royal Victoria Hospital in Belfast, Northern Ireland Dec. 8, 2020.POOL/Reuters
There were no cases of severe allergic reactions to Pfizer Inc and partner BioNTech SE’s COVID-19 vaccine candidate during clinical trials, a Pfizer executive said at a regulatory conference on Friday.
A late-stage trial testing the potential vaccine excluded participants who had a prior history of severe allergic reactions to any vaccine or to the constituents of Pfizer/BioNTech vaccine, said Dr. William Gruber, Pfizer’s senior vice president of vaccine clinical research and development.
“We’ve not had any anaphylactic episodes related to the vaccine,” Gruber said during a panel meeting of independent advisers to the U.S. Centers for Disease Control and Prevention.
The trial included about 6,000 participants respectively in both the vaccine and placebo groups with a history of a range of allergic conditions like pollen allergy, food allergy, all the way up to anaphylaxis, Pfizer executive Susan Mather said.
Anaphylaxis is an overreaction by the body’s immune system that could sometimes be life-threatening.
The comments follow British medicine regulator’s advice that people with a history of significant allergic reactions do not get the Pfizer-BioNTech’s vaccine after two people reported adverse effects.
The U.S. Food and Drug Administration is expected to issue an emergency use authorization for the two-dose vaccine as soon as Friday, according to the New York Times.
Once authorized, the first Americans could be immunized as soon as Monday or Tuesday, with health care workers expected to be among the first in line.
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