FOI release

Freedom of Information request about adverse drug reactions (ADR) to COVID-19 vaccines (FOI-21-115)

Published 28 April 2021

Thank you for your recent correspondence dated on 4th February 2021, where you asked for information on the following:

1. “Number of cases to date of allergic anaphylactic reactions for each of the licenced Covid-19 vaccines”
2. “If the number of cases to date of allergic anaphylactic reactions will also be published on the website?”

Two COVID-19 vaccines, Pfizer/BioNTech and Oxford University/AstraZeneca vaccines, are currently being used in the UK. Both have been authorised for supply by the Medicines and Healthcare products Regulatory Agency (MHRA) following a thorough review of safety, quality and efficacy information from clinical trials. All vaccines and medicines have some side effects. These side effects need to be continuously balanced against the expected benefits in preventing illness.

The MHRA’s role is also to continually monitor safety during widespread use of a vaccine. Any member of the public or health professional can submit suspected side effects through the Yellow Card scheme. The nature of Yellow Card reporting means that reported events are not always proven side effects. Some events may have happened anyway, regardless of vaccination. This is particularly the case when millions of people are vaccinated, and especially when most vaccines are being given to the most elderly people and people who have underlying illness.

I can confirm that data on reported suspected side effects to the approved Covid-19 vaccines is currently published on the MHRA website and this information will be updated on a weekly basis (https://www.gov.uk/government/publications/coronavirus-covid-19-vaccine-adverse-reactions/coronavirus-vaccine-summary-of-yellow-card-reporting).

From this report you can see that the MHRA has received 168 UK spontaneous adverse reactions associated with anaphylaxis or anaphylactoid reactions with the Pfizer/BioNTech vaccination up to 14 February 2021. All patients have recovered from the anaphylaxis episode. 105 reports of anaphylaxis have been received for the COVID-19 Oxford University/AstraZeneca vaccine up to 14th February 2021.

On 9 December 2020, following receipt of two reports, the MHRA took immediate precautionary action and issued advice that people with a history of anaphylaxis to any medicine, vaccine or food should not receive the Pfizer/BioNTech vaccine. However, following review of further data by the Commission on Human Medicines (CHM), updated guidance was issued on 30 December 2020 stating that only those with a previous history of allergic reactions to the ingredients of the vaccine should not receive it. This advice was added to the information for healthcare professionals and UK recipients about the Pfizer/BioNTech vaccine. Widespread use of the vaccine now suggests that severe allergic reactions to the Pfizer/BioNTech vaccine are very rare, reported at a rate between 1 and 2 cases per 100,000 doses administered. Please be assured that all these reports are continuously being monitored.

I hope the information provided is helpful, but if you are dissatisfied with the handling of your request, you have the right to ask for an internal review. Internal review requests should be submitted within two months of the date of this response; and can be addressed to this email address.

Yours sincerely,

FOI Team, Vigilance and Risk Management of Medicines Division