Q&A: ACAAI releases guidance about Pfizer's COVID-19 vaccine in patients with allergies

The American College of Allergy, Asthma and Immunology’s COVID-19 Task Force released guidance on allergic reaction risk from the Pfizer-BioNTech COVID-19 vaccine.

Shortly before the FDA finalized an emergency use authorization for the vaccine last week, health authorities in the United Kingdom advised against giving it to patients who had a history of allergic reaction after two health care workers who received the vaccine experienced allergic symptoms.

In the guidance, the American College of Allergy, Asthma and Immunology (ACAAI) recommended discussing the benefits vs. the risks with patients who have common allergies, and recommended against vaccinating those with a history of severe allergies to polyethylene glycol.

The ACAAI also recommended that the vaccine be administered in settings where anaphylaxis can be treated, and that patients be monitored for adverse reactions after injection.

Healio Primary Care spoke with Niraj Patel, MD, chair of the ACAAI’s COVID-19 Task Force and professor of pediatric infectious disease and immunology at Levine Children’s Hospital in Charlotte, N.C., to learn more about the guidance.

Q: Why is this guidance needed?

A: Allergic reactions to vaccines, in general, are rare, with the incidence of anaphylaxis estimated at 1.31 in 1 million doses given. With the emergency use authorization of the Pfizer-BioNTech COVID-19 vaccine by the FDA on Dec. 11, it is important that guidance be available to physicians and other providers related to risk of an allergic reaction on vaccination. The recommendations are based on best knowledge to date but could change at any time, pending new information and further guidance from the FDA or CDC.

Q: What should primary care physicians tell patients with common food and medication allergies and those who are immunocompromised about the vaccine?

Individuals with common allergies to medications, foods, inhalants and insects are no more likely than the general public to have an allergic reaction to the Pfizer-BioNTech COVID-19 vaccine. Those patients should be informed of the benefits of the vaccine versus its risks. The Pfizer-BioNTech COVID-19 vaccine is not a live vaccine and can be administered to immunocompromised patients.

Physicians and other providers should inform such immunocompromised patients of the possibility of a diminished immune response to the vaccine.

Q: How should physicians monitor for anaphylaxis after vaccination?

A: The Pfizer-BioNTech COVID-19 vaccine should be administered in a health care setting where anaphylaxis can be treated. All individuals must be observed for at least 20 to 30 minutes after injection to monitor for any adverse reaction. All anaphylactic reactions should be managed immediately with IM epinephrine as the first-line treatment.

Q: Which patients should not receive the Pfizer-BioNTech COVID-19 vaccine due to concerns of allergic reaction?

A: The Pfizer-BioNTech COVID-19 vaccine should not be administered to individuals with a known history of a severe allergic reaction to polyethylene glycol as it is a component of this vaccine known to cause anaphylaxis. Data related to risk in individuals with a history of allergic reactions to previous vaccinations and/or mast cell activation syndrome/idiopathic anaphylaxis is very limited and evolving. A clinical decision to administer the Pfizer-BioNTech COVID-19 vaccine should be undertaken by the physician or other provider administering the vaccine using their professional judgment and in consultation with the patient, balancing the benefits and risks associated with taking the vaccine.

Q: Are mRNA vaccines more likely to induce allergic reactions than other vaccines?

A: It does not appear at this time that mRNA vaccines are more likely to induce allergic reactions compared to other vaccines. In the Pfizer-BioNTech COVID-19 vaccine clinical trial, no allergic reactions or serious adverse events were reported in over 40,000 participants.

Q: Health authorities in the U.K. advised against giving the Pfizer-BioNTech vaccine to patients with a history of allergic reaction. Should authorities in the U.S. do the same? Why or why not?

There is limited information regarding the two subjects in the U.K. who had an allergic reaction following administration of the vaccine. It is likely that there were subjects in the Pfizer-BioNTech COVID-19 vaccine trial who had common allergies to food or medications who tolerated the vaccine, although it is not clear if this data was collected or if it will be available. The Pfizer-BioNTech COVID-19 vaccine should not be administered to anyone with a history of an allergic reaction to any of the vaccine components, but in particular polyethylene glycol as it is a component known to cause anaphylaxis. Again, individuals with common allergies to medications, foods, inhalants and insects are no more likely than the general public to have an allergic reaction to the Pfizer-BioNTech COVID-19 vaccine. Those patients should be informed of the benefits of the vaccine versus its risks.

References:

ACAAI. American College of Allergy, Asthma, and Immunology Releases Guidance on Risk of Allergic Reactions to the Pfizer-BioNTech COVID-19 Vaccine. https://acaai.org/news/american-college-allergy-asthma-and-immunology-releases-guidance-risk-allergic-reactions-pfizer. Accessed December 16, 2020.