Abstract
Introduction: Facial paralysis is a loss of facial movement due to nerve damage. Common causes of facial paralysis include infection or inflammation of the facial nerve, head trauma, head or neck tumor, or stroke (1). Pembrolizumab is an antineoplastic agent. It is a humanized monoclonal antibody that binds to the programmed cell death-1 (PD-1) receptor. A signal of Pembrolizumab and facial paralysis was found in the medical literature. Saudi Food and Drug Authority (SFDA) has conducted this safety review based on that. Objective: The purpose of this review is to evaluate the risk of facial paralysis in association with Pembrolizumab use Methods: SFDA performed a search of the national ADRs database, World Health Organization (WHO) global ADRs database, and literature screening in order to review all related information to investigate the causality of drug-event combination Results: Local Cases: The search in the National Pharmacovigilance Center (NPC) database resulted in zero cases. Global Cases: A search in the World Health Organization (WHO) database (Vigibase) was conducted to retrieve all reported cases between 2015 and 2021 via signal detection tool (Vigilyze). The search resulted in 28 Individualized Case Safety Reports (ICSRs). The author applied the WHO causality assessment, resulting in one case with probable association, six cases with the possible association, and five cases with unlikely association. Sixteen cases were unassessable due to a lack of information. Data mining: Information Component (IC) value was measured using the method for disproportionality analysis developed by Uppsala Monitoring Center (UMC). Zero value for spontaneous reporting suggests that the reported cases of facial paralysis have been observed equally with Pembrolizumab when compared to other medications in the WHO database. Literature: Upon conducting a literature search, two relevant studies were found. This signal was detected from a phase 3 double-blind trial entitled (Adjuvant Pembrolizumab after Nephrectomy in Renal-Cell Carcinoma). Facial paralysis was one of the identified serious adverse events (4). A case report of a 44-year-old male patient was diagnosed with extensivestage small-cell lung cancer (ES-SCLC). 6 months after receiving pembrolizumab, he developed facial paralysis and facial numbness. Pembrolizumab was stopped (5). Conclusion: The weighted cumulative evidence identified from the causality assessment of the reported cases, and literature are sufficient to support a causal association between Pembrolizumab and the risk of facial paralysis. Health regulators and health care professionals must be aware of this potential risk and it is advisable to monitor any signs or symptoms in treated patients