A real-world pharmacovigilance study of efgartigimod alfa in the FDA Adverse Event Reporting System database

Yunlin Yang ¹ Jinfeng Liu ² Wei Wei ^2*

• ¹ Department of Clinical Pharmacy, Shifang People's Hospital, Shifang, China
• ² Department of Pharmacy, People's Hospital of Zhongjiang County, Deyang, China

Objective: Efgartigimod alfa, approved for the treatment of generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive, has limited long-term safety data in large populations. This study aimed to analyze adverse events (AEs) associated with efgartigimod alfa using data from the FDA Adverse Event Reporting System (FAERS).Methods: Data collection and analysis were conducted on efgartigimod alfa-related reports from the FAERS database, spanning from the first quarter of 2022 to the second quarter of 2024. Disproportionality analysis was employed in data mining to quantify adverse event (AE) signals associated with efgartigimod alfa.Results: The analysis based on the FAERS database yielded 3,040 reports with efgartigimod alfa as the primary suspect, encompassing 12,487 adverse events (AEs). Hospitalization was the most frequently reported serious outcome (53.22%), with fatalities occurring in 270 cases (8.88%). Disproportionality analysis identified 137 AE signals, predominantly in nervous system disorders (22.69%), general disorders and administration site conditions (16.90%), and infections and infestations (14.05%). Notably, this study uncovered unexpected signals beyond the infection-related AEs identified in clinical trials, including inappropriate schedule of product administration reporting odds ratio (ROR) 2.60, proportional reporting ratio (PRR) 2.53, information component (IC) 1.34, empirical Bayes geometric mean (EBGM) 2.53 and nephrolithiasis (ROR 8.13, PRR 7.99, IC 2.99, EBGM 7.95). The median onset time for AEs was 81.0 days.Conclusion: This study offers a thorough evaluation of efgartigimod alfa's post-marketing safety profile, emphasizing the necessity for ongoing monitoring of infection-related adverse events. Furthermore, the identification of improper product administration schedules underlines the critical need for enhanced training and increased pharmacist involvement in medication management. Additional research is necessary to investigate the potential link between efgartigimod alfa and nephrolithiasis.