Is there information on the patients who suffered anaphylaxis after receiving the Pfizer-BioNTech COVID-19 vaccine? Specifically with a focus on their symptoms and time to onset?

Is there information on the patients who suffered anaphylaxis after receiving the Pfizer-BioNTech COVID-19 vaccine? Specifically with a focus on their symptoms and time to onset?

Comment by InpharmD Researcher

Early data suggests the incidence of true anaphylaxis to the Pfizer-BioNTech COVID-19 vaccine is rare (11.1 cases per million vaccine doses). Anaphylaxis is more common in women and persons with a history of allergies, and symptoms typically appear within 30 minutes of injection.

Background

A preliminarily released report of Pfizer/BioNTech's COVID-19 vaccine candidate, BNT162b2, shows that unsolicited adverse events occurred in 577/4,058 (14.2%) patients during phase 2/3 clinical trials. Of all presented data (cutoff date: November 14, 2020), adverse events potentially representing hypersensitivity-related adverse events were more common in the vaccine group (137 [0.63%]) compared with the placebo group (111 [0.51%]). The frequency of immediate adverse events reported in the vaccine group was 0.4% after Dose 1 and <0.3% after Dose 2 and were mainly consistent with solicited reactogenicity events. In both study groups, the most frequently reported immediate AE was injection site pain (BNT162b2 vaccine 0.3%, placebo 0.2%). Severe adverse reactions occurred in 0.0-4.6% of participants, were more frequent after Dose 2 than after Dose 1, and were generally less frequent in older adults (>55 years of age) (<2.8%) as compared to younger participants (≤4.6%). The most common solicited adverse reactions were injection site reactions (84.1%), fatigue (62.9%), headache (55.1%), muscle pain (38.3%), chills (31.9%), joint pain (23.6%), fever (14.2%). [1]

A placebo-controlled, observer-blinded, dose-escalation, phase 1 trial studied the safety of Pfizer/BioNTech's COVID-19 vaccine candidates, BNT162, assessed the safety of three vaccine doses in 332 adults. Of the two candidates studied, BNT162b2 was associated with a lower incidence and severity of systemic reactions than BNT162b1, particularly in older adults. Among the older participants, mild-to-moderate injection-site pain was reported by 92% after the first dose and by 75% after the second dose. Severe systemic events (fatigue, headache, chills, muscle pain, and joint pain) in response to BNT162b2 were milder than those in response to BNT162b1. No events of hypersensitivity or anaphylaxis were reported. [2]

A small, phase 1, dose-escalation, open-label trial of Moderna's COVID-19 vaccine candidate, mRNA-1273, was studied in 40 adults. Solicited adverse events were predominantly mild or moderate in severity and most frequently included fatigue, chills, headache, myalgia, and pain at the injection site. No serious adverse events were reported. [3]

Literature Review

A search of the published medical literature revealed 1 study investigating the researchable question:

Is there information on the patients who suffered anaphylaxis after receiving the Pfizer-BioNTech COVID-19 vaccine? Specifically with a focus on their symptoms and time to onset?

Please see Table 1 for your response.

Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine — United States, December 14–23, 2020
Design	Case series N=21
Objective
Inclusion Criteria	Reported allergic adverse events after receiving the Pfizer-BioNTech COVID-19 vaccine
Exclusion Criteria	Nonallergic adverse events (vasovagal or anxiety-related)
Methods	This is a report of suspected severe allergic reactions and anaphylaxis following vaccination with the Pfizer-BioNTech COVID-19 vaccine captured by the Vaccine Adverse Event Reporting System (VAERS). From December 14 to 23, 2020, 1,893,360 first doses of Pfizer-BioNTech COVID-19 vaccine were reported. Of these, 21 case reports met the Brighton Collaboration definition for anaphylaxis (11.1 cases per million doses administered).
Baseline Characteristics		Anaphylaxis (n=21)		Nonanaphylaxis allergic reactions (n=83)
	Age, years (range)	40 (27-60)		43 (18-65)
	Female	19 (90%)		75 (90%)
	Minutes to onset (range)	13 (2-150)		12 (<1-1,200)
Results	Age/sex	Past history		Time to onset (minutes)	Signs and symptoms	Outcome
	Age/sex	Allergies	Previous anaphylaxis	Time to onset (minutes)	Signs and symptoms	Outcome
	27/F	Tropical fruit	None	2	Diffuse erythematous rash, sensation of throat closure	Recovered at time of report
	35/M	None	None	5	Diffuse erythematous rash, swollen tongue	Discharged home
	55/F	Rabies vaccine	Rabies vaccine	5	Generalized urticaria, wheezing	Discharged home
	52/F	Sulfa drugs	Sulfa drugs	7	Wheezing, stridor, nausea	Discharged home
	30/F	Bee sting	None	8	Generalized urticaria, wheezing	Recovered at time of report
	32/F	None	None	10	Diffuse erythematous rash, difficulty breathing	Discharged home
	60/F	Dairy, sulfa drugs	Jellyfish sting	10	Diffuse erythematous rash, hoarseness	Recovered at time of report
	29/F	Shellfish, eggs	None	10	Generalized urticaria, swollen lips and tongue	Discharged home
	52/F	Metoprolol, clarithromycin	None	10	Generalized urticaria, stridor, wheezing	Recovered at time of report
	49/F	Iodinated contrast media	None	13	Generalized urticaria, swollen throat	Recovered at time of report
	36/F	None	None	13	Generalized urticaria, nausea	Recovered at time of report
	40/F	Sulfa drugs, walnuts	Walnuts	14	Generalized urticaria, nausea	Discharged home
	33/F	Wasp sting	None	15	Diffuse erythematous rash, swollen lip	Recovered at time of report
	41/F	Prochlorperazine	Prochlorperazine	15	Diffuse erythematous rash, persistent dry cough	Discharged home
	57/F	Penicillin, azithromycin	Unspecified	15	Diffuse pruritic rash, hoarseness	Recovered at time of report
	45/M	None	None	23	Generalized urticaria, swollen airway	Discharged home
	46/F	Hydrocodone, nuts	None	25	Diffuse erythematous rash, difficulty swallowing	Discharged home
	30/F	Cats, dogs	None	30	Generalized pruritis, wheezing	Discharged home
	44/F	Influenza vaccine	Influenza vaccine	34	Generalized urticaria, swollen lips	Discharged home
	29/F	Sulfa drugs	None	54	Generalized urticaria, persistent cough	Recovered at time of report
	29/F	Steroids	None	150	Diffuse pruritic rash, swollen lip	Discharged home
Study Author Conclusions	Early safety monitoring of the Pfizer-BioNTech COVID-19 vaccine has detected 21 cases of anaphylaxis after reported administration of 1,893,360 first doses of Pfizer-BioNTech COVID-19 vaccine (11.1 cases per million vaccine doses administered) as well as cases of less severe nonanaphylaxis allergic reactions, based on U.S. data for December 14–23, 2020. Most (86%) anaphylaxis cases had symptom onset within 30 minutes of vaccination, and most persons with anaphylaxis (81%) had a history of allergies or allergic reactions, including some with previous anaphylaxis events; up to 30% of persons in the general population might have some type of allergy or history of allergic reactions. Most (90%) reported anaphylaxis cases after receipt of Pfizer-BioNTech COVID-19 vaccine occurred in women, although 64% of the vaccine doses administered with sex of recipient recorded were given in women.
InpharmD Researcher Critique	This is data reported from the first week of immunizations of the Pfizer-BioNTech COVID-19 vaccine. Nonreported data is not included, and the time-frame is relatively short. Still, this data suggest the incidence of true anaphylaxis to the mRNA COVID-19 vaccines is rare (11.1 cases per million vaccine doses).

References:

Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine — United States, December 14–23, 2020. MMWR Morb Mortal Wkly Rep 2021;70:46–51. DOI: http://dx.doi.org/10.15585/mmwr.mm7002e1

Shimabukuro T, Nair N. Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine. JAMA. 2021;325(8):780–781. doi:10.1001/jama.2021.0600