UK issues allergy warning on Pfizer Vaccine after adverse reactions
Britain's medicine regulator said anyone with a history of anaphylaxis to a medicine or food should not get the Pfizer-BioNTech COVID-19 vaccine, giving fuller guidance on an earlier allergy warning about the shot.
Starting with the elderly and frontline workers, Britain began mass vaccinating its population on Tuesday, part of a global drive that poses one of the biggest logistical challenges in peacetime history.
The Medicines and Healthcare Products Regulatory Agency (MHRA) said there had been two reports of anaphylaxis and one report of a possible allergic reaction since rollout began.
"Any person with a history of anaphylaxis to a vaccine, medicine or food should not receive the Pfizer BioNTech vaccine," MHRA Chief Executive June Raine said in a statement.
"Most people will not get anaphylaxis and the benefits in protecting people against COVID-19 outweigh the risks... You can be completely confident that this vaccine has met the MHRA's robust standards of safety, quality and effectiveness.
Allergic Reaction
MHRA chief Raine told lawmakers such allergic reactions had not been a feature of the Pfizer's clinical trials.
Pfizer has said people with a history of severe adverse allergic reactions to vaccines or the candidate's ingredients were excluded from their late stage trials, which is reflected in the MHRA's emergency approval protocol.
However, the allergic reactions may have been caused by a component of Pfizer's vaccine called polyethylene glycol, or PEG, which helps stabilise the shot and is not in other types of vaccines.
In the United States, the FDA released documents on Tuesday in preparation for an advisory committee meeting on Thursday, saying the Pfizer vaccine's efficacy and safety data met its expectations for authorization.
The briefing documents said 0.63% of people in the vaccine group and 0.51% in the placebo group reported possible allergic reactions in trials, which Peter Openshaw, professor of experimental medicine at Imperial College London, said was a very small number.
