Received Sep 26, 2025
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| COVID19 | COVID19 (COVID19 (PFIZER-BIONTECH)) | PFIZER\BIONTECH | 1 | — | — |
Mast Cell Activation Syndrome; Known allergies; This is a spontaneous report received from an Other HCP from a sales representative. A female patient (not pregnant) received BNT162b2 omicron (lp.8.1) (COMIRNATY (2025-2026 FORMULA)), as dose 1, single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Bnt162b2 (DOSE 1, SINGLE), for Covid-19 Immunization; Bnt162b2 (DOSE 2, SINGLE), for Covid-19 Immunization; Bnt162b2 (DOSE 3 (BOOSTER), SINGLE), for Covid-19 Immunization. The following information was reported: MAST CELL ACTIVATION SYNDROME (disability), outcome "not recovered"; HYPERSENSITIVITY (non-serious), outcome "unknown", described as "Known allergies". Clinical course: Patient believes she acquired Mast Cell Activation Syndrome as a result of the 4 separate Comirnity vaccines she received during the COVID 19 Pandemic. The event result in Disability or permanent damage. The patient had known allergies and she believes this started as a result of the Comirnity vaccination she received during (as reported). Therapeutic measures were taken as a result of mast cell activation syndrome, hypersensitivity included took multiple medications and supplements to keep her condition under control. The information on the batch/lot number for BNT162b2 omicron (lp.8.1) will be requested and submitted if and when received.; Sender's Comments: As there is limited information in the case provided, the causal association between the event mast cell activation syndrome and the suspect drug BNT162B2 OMICRON (LP.8.1) cannot be excluded. The case will be reassessed once new information is available. The impact of this report on the benefit-risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, ethics committees and investigators, as appropriate.