Antiviral influenza treatments and hemorrhage‐related adverse events in the United States Food and Drug Administration Adverse Event Reporting System (FAERS) database

STUDY OBJECTIVE: To determine whether there is a signal for gastrointestinal (GI) or intracranial (IC) hemorrhage associated with the use of antiviral medications for influenza in the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database. DESIGN: Disproportionality analysis. DATA SOURCE: The FAERS database was searched using OpenVigil 2.1 to identify GI and IC hemorrhage events reported between 2004 and 2022. MEASUREMENTS: Antiviral medications for influenza included the following: oseltamivir, zanamivir, peramivir, and baloxavir marboxil. Hemorrhage events were identified using Standardized Medical Dictionary for Regulatory Activities (MedDRA) Queries for GI and IC hemorrhages. Reporting odds ratios (RORs) were calculated to compare the occurrence of GI and IC hemorrhage events between antiviral drugs for influenza and (i) all other medications and (ii) antibiotics. RORs were also calculated for each of the individual antiviral medications. MAIN RESULTS: A total of 245 cases of GI hemorrhage and 23 cases of IC hemorrhage were identified in association with four antivirals. In comparison with all other drugs, the RORs of GI hemorrhage for oseltamivir, zanamivir, peramivir, baloxavir, and all antivirals combined were 1.17, 0.62, 4.44, 2.53, and 1.22, respectively, indicating potential variations in GI hemorrhage risk among the antivirals. In contrast, in comparison with all other drugs, the RORs of IC hemorrhage for oseltamivir (0.44), zanamivir (0.16), baloxavir (0.44), and all antivirals combined (0.41) were less than 1.0 which is consistent with no elevated risk of IC hemorrhage. CONCLUSION: In this study, some signals for GI hemorrhage were observed, particularly for peramivir and baloxavir marboxil. Further investigation is warranted to better understand and evaluate the potential risks of GI hemorrhage associated with antiviral treatments for influenza.