BSACI update on the Reactions to the Pfizer COVID-19 Vaccination 15.12.2020

Following BSACI statement on 09.12.2020 (see here) relating to the reports of allergic reactions to the Pfizer COVID-19 vaccination. It has become clear that there were at least two serious allergic reactions which occurred rapidly after vaccination, although the exact cause is as yet unclear. As a result, the MHRA issued updated guidance, advising against using the vaccine in any patient with a history of anaphylaxis to either a drug, vaccine or food. The BSACI remains wholeheartedly supportive of the vaccination programme and pending full evaluation of the suspected cases, we acknowledge the position of the regulator, whilst noting that this will present very real challenges to vaccination centres and our members who are likely to be consulted for advice.

A lot of press coverage has focussed on the possibility of Polyethylene Glycol (PEG), a recognised but rare cause of severe reactions, being the cause. The BSACI flagged this to the Chief Medical Officer in the days preceding the campaign and whilst this does seem a very real possibility, we need to consider the potential for other possible causes.  With the central coordination of the NHS, the patients suspected of severe reactions will be referred to a Specialist Drug Allergy clinic to undergo detailed evaluation. This will help us better understand how the current advice from the MHRA will need to evolve to mitigate against the risk of severe reactions in vaccine recipients, while minimising unnecessary restriction of vaccination. This is especially important for those at greatest risk from COVID-19. It is worth noting that the supply of the Pfizer vaccine is limited and will most likely only form a small part of the overall vaccine programme, with the majority anticipated to come from the Oxford/Astra Zeneca vaccine which is a wholly different preparation and does not contain PEG.

Regulators including those in the United States and Canada have approved the Pfizer vaccine but not placed the same restrictions with regards to patients with a history of anaphylaxis. BSACI will of course be watching closely to see the outcome of the early stages of these vaccination programmes. The BSACI has been active around this issue beyond the work of those members who have also been working directly with the regulatory agencies. In conjunction with the Resuscitation Council UK, the RCGP and Public Health England, we have produced a short document summarising the management of anaphylaxis in the vaccination setting, which can be found here, and will be circulated to all vaccination centres.

We have worked closely with Allergy UK and the Anaphylaxis Campaign to support them in the developments of FAQs for the large number of patients who have contacted their helplines. This helps ensure consistency and accuracy of the advice given to patients. We plan to continue to support them in this way and look forward to working closely together with them.

We have established a working group of clinicians with specific expertise in vaccine and drug allergy, who will be supporting the decision making by the BSACI, and provide input to the MHRA. The group will be chaired by Dr Shuaib Nasser (Addenbrookes, Cambridge). We have been actively liaising with senior members of our sister societies around the world who are understandably keen to hear about our findings. BSACI are planning a webinar that will bring together everything we know about the current issue, along with a range of UK drug allergy experts to ensure that members are as well informed as possible. Further information will be posted on the website in due course. We have also collated a list of adult drug allergy clinics that can be accessed from the website here, in anticipation of increased referrals following a likely range of adverse reactions to the vaccine.

BSACI will continue to work closely with the MHRA as the situation evolves and will of course keep you updated accordingly. I would like to personally thank all those colleagues who have directly supported the society’s response,

Prof Adam Fox, BSACI President on behalf of the BSACI council