(270) Pfizer-BioNTech COVID-19 Vaccine and The Potential Risk of Hypoesthesia: Analysis of The Global and Local Individual Case Safety Reports

Publication Number: 1315

Background: Hypoesthesia is also known as numbness, which corresponds to the loss of normal feeling or sensation. Several factors are associated with the occurrence of hypoesthesia such as spine/spinal cord disorder, diabetes, anxiety, depression, or neuropathy causing nerve dysfunction, and muscle and vascular diseases. In December 2020, Pfizer-BioNTech vaccine was conditionally authorized by the Saudi Food and Drug Authority (SFDA) to combat coronavirus disease 2019 (COVID-19).

Objectives: To assess the potential risk of hypoesthesia with the use of Pfizer-BioNTech Covid-19 vaccine.

Methods: A descriptive analysis was conducted of all hypoesthesia reported cases associated with the use of Pfizer-BioNTech Covid-19 vaccine. On January 21, 2021, a search was conducted in the World Health Organization (WHO) database (VigiBase) to retrieve all the reported cases between 2019 and 2021 using the terms “Covid-19 vaccine” OR “Comirnaty” OR “COVID 19 mRNA Vaccine BNT162b2” OR “Pfizer BioNTech COVID 19 vaccine” [AND] “Hypoaesthesia” OR “Numbness”. Moreover, a search was conducted in the local adverse reactions database of the National Pharmacovigilance Centre in Saudi Arabia to retrieve the reported cases locally. Then, the causality assessment of the cases was performed using the WHO-Uppsala Monitoring Center causality system.

Results: The search in VigiBase revealed 526 case-reports of hypoesthesia reported with Pfizer-BioNTech Covid-19 vaccine. The top 30 ICSRs with the highest completeness score were included in the analysis. The mean age was 40 years (range 22 – 58) and the majority of the cases were reported with females (80%). In all the cases, Pfizer-BioNTech Covid-19 vaccine was reported as the only suspected agent. The outcome of the majority of the cases was reported as recovered (73%). In addition, 14 cases of hypoesthesia were identified in the local database and were included in the analysis. The mean age was 36.1 years (range 30 – 80) and the majority of the cases were reported with females (64%). In all the cases, Pfizer-BioNTech Covid-19 vaccine was reported as the only suspected agent. The outcome of the majority of the cases was not reported. Overall, all the reported cases had no history nor any risk factors of hypoesthesia. The time to onset in all the included cases ranged between 1 – 2 days after vaccination, which showed a reasonable temporal relationship. The causality assessment showed that all the cases were possibly related to the vaccine except for 2 cases that were unassessable due to insufficient information.

Conclusions: The study shows a possible association between hypoesthesia and Pfizer-BioNTech Covid-19 vaccine. However, further assessment by well-designed pharmacoepidemiological studies is needed to confirm the association.