Adverse events associated with oseltamivir and baloxavir marboxil in against influenza virus therapy: A pharmacovigilance study using the FAERS database
Authors: Zhou Yixia , Jin Liuyin , Lai Xiaolong , Li Yang , Sheng Lindan , Xie Guoming , Fang Jianjiang 
Published: November 2024

Background
Influenza virus is a widespread pathogen that poses significant health risks to humans. Oseltamivir and Baloxavir Marboxil are commonly utilized medications for both treating and preventing influenza infections. Despite their widespread use, there remains a need to thoroughly investigate their safety profiles and potential adverse reactions.

Objective
This study aims to comprehensively analyze the adverse events associated with oseltamivir and baloxavir marboxil in real-world clinical settings, with the goal of assessing their safety and potential risks in the management of influenza virus infections.

Methods
We conducted a retrospective analysis utilizing data from the Food and Drug Administration Adverse Event Reporting System (FAERS) database, spanning from the first quarter of 2004 to the third quarter of 2023. The analysis encompassed examination of drug utilization patterns, types of adverse events reported, patient demographics, and other pertinent factors.

Results
From the first quarter of 2004 to the third quarter of 2023, FAERS collected over 17,035,521 adverse event reports (AE reports). Among these reports, there were 38,384 reports associated with oseltamivir, and 3,364 reports associated with baloxavir marboxil. Oseltamivir and Baloxavir Marboxil were primarily used for the treatment of influenza virus infections, accounting for 62.43% and 67.49% of their total usage, respectively. The main adverse reactions reported for oseltamivir were vomiting (case reports = 1402) followed by confusional state (case reports = 353), while for baloxavir marboxil, adverse reactions mainly centered around off-label use (case reports = 378) and intentional product use issues (case reports = 278). In terms of systemic adverse reactions, oseltamivir primarily affected psychiatric disorders (n = 45), whereas baloxavir marboxil mainly impacted the gastrointestinal system (n = 7). Additionally, regarding adverse reactions in pregnant women, the occurrence of normal newborns was a significant signal for oseltamivir, suggesting a certain level of safety during maternal use. Conversely, reports of adverse reactions such as respiratory arrest were documented for baloxavir marboxil, while no such reports were associated with oseltamivir.

Conclusion
This study provides a comprehensive analysis of the adverse reactions observed with the clinical use of oseltamivir and baloxavir marboxil, revealing the safety and risks associated with these two drugs in the treatment and prevention of influenza virus infections. Firstly, although both drugs are used for influenza treatment, they exhibit different types of adverse reactions. Oseltamivir predominantly affects the psychiatric system, while baloxavir marboxil primarily impacts the gastrointestinal system. Additionally, oseltamivir demonstrates a certain level of safety for use in pregnant women, while reports of adverse reactions such as respiratory arrest are associated with baloxavir marboxil. Despite the clinical significance of this study, limitations exist due to the voluntary nature of data reporting, which may lead to reporting biases and incomplete information. Future research could employ more rigorous prospective study designs, integrating clinical trials and epidemiological studies, to more accurately assess the safety risks of oseltamivir and baloxavir marboxil.