Detection of Signal and Analysis of Adverse Event of Pirfenidone Using World Health Organization VigiBase

Objective: Pirfenidone, an antifibrotic for Idiopathic Pulmonary Fibrosis (IPF), is associated with adverse events (AEs), including gastrointestinal and dermatological side effects.AE characteristics vary across regions due to genetic and environmental factors, necessitating global database analysis.This study aimed to detect pirfenidone-related signals via World Health Organization (WHO) VigiBase and compare findings with approved labels from Korea, the United States, and Japan.Methods: Using VigiBase data (2014-2024), we identified pirfenidone-related AEs based on the WHO Anatomical Therapeutic Chemical (ATC) classification system (L04AX05) and extracted data using substance names recorded in VigiBase.Nintedanib (ATC code: L01EX09) was selected as a comparator.AEs were coded using the Medical Dictionary for Regulatory Activities (MedDRA) Preferred Terms (PTs) and mapped to System Organ Classes (SOCs).Signal detection was conducted using disproportionality analysis, employing the Reporting Odds Ratio (ROR) and Bayesian Confidence Propagation Neural Network (BCPNN) methods.Significant signals were defined as ROR 2 with chi-squared 4 and an IC lower bound 0 at a 95% confidence interval.Detected signals were compared with approved labels.Results: Among 101,480 pirfenidone-related AEs, notable regional differences were identified.While known AEs such as skin and general disorders were observed, neurological and psychiatric disorders also emerged.Seven signals absent in Korea's label were critically analyzed.Conclusion: This study highlights regional differences in pirfenidone-related AEs and identifies new signals, emphasizing the need for enhanced regulatory measures, further research, and proactive monitoring to ensure safe antifibrotic use.(PeRM 2025;