Post-marketing safety of anti-IL-5 monoclonal antibodies (mAbs): an analysis of the FDA Adverse Event Reporting System (FAERS)

BACKGROUND: Anti-IL-5 monoclonal antibodies (mAbs) targeting IL-5 or IL-5 R α (including mepolizumab, benralizumab, and reslizumab) are widely used for inflammatory diseases such as asthma, eosinophilia, and polyangiitis. However, real-world data regarding its safety in a large sample population are incomplete. So, we evaluated the safety of anti-IL-5 mAbs by pharmacovigilance analyzes based on related adverse events (AEs) from the FDA Adverse Event Reporting System (FAERS). METHODS: In disproportionality analysis, four algorithms were employed to detect the signals of anti-IL-5 mAbs from the FAERS between 2016 and 2022. In addition, we also used MYSQL 8.0, Navicat Premium 15, and Microsoft EXCEL 2019 to analyze the signals of anti-IL-5 mAbs systematically. RESULTS: There are 9,476,351 reports collected from the FAERS database, of which 22,174 reports listed anti-IL-5 mAbs as the 'primary suspected (PS)' drug. A total of 59 (20 new signals, mepolizumab) and 62 (19 new signals, benralizumab) significant disproportionality preferred terms (PTs) conforming to the four algorithms were retained synchronously. Finally, we detected that the anti-IL-5 mAbs-induced AEs occurred in 31 organ systems (mepolizumab) and 30 organ systems (benralizumab). For mepolizumab and reslizumab, unexpected and new significant PTs of AEs were found, such as asthmatic crisis, chronic obstructive pulmonary disease (COPD), pneumonia, COVID-19, pneumothorax, adrenal insufficiency and so on. Notably, the risk signal of asthmatic crisis for mepolizumab was stronger than benralizumab (ROR 108.04 [95%CI, 96.09-121.47] vs 26.83 [95%CI, 18.91-38.06]). Comparing with mepolizumab and benralizumab, we found the proportion of serious adverse events in mepolizumab was both greater than benralizumab in each age group (≤20, 20-65, and ≥ 65). The median onset time of mepolizumab was 280 days (interquartile range [IQR] 1-367 days). CONCLUSION: Analysis of FAERS data identified anti-IL-5 mAbs-associated AEs, and our findings supported continuous clinical monitoring, pharmacovigilance, and further studies of anti-IL-5 mAbs. In addition, clinicians may be more aware of the limitations of use in package inserts of anti-IL-5 mAbs: Not for relief of acute bronchospasm or status asthmaticus. Because of some limitations in the FAERS such as self-reports from patients and other confounding factors, the safety of anti-IL-5 mAbs needed more studies in different dimensions, especially the risk of cancer.