Comprehensive Analysis of Ixazomib-Induced Adverse Events Using the Japanese Pharmacovigilance Database

Background: Ixazomib is an orally available proteasome inhibitor for multiple myeloma with adverse effects such as gastrointestinal symptoms, skin rashes, and thrombocytopenia reported in clinical trials and post-marketing surveillance, resulting in treatment discontinuation. However, comprehensive adverse event (AE) assessments for ixazomib are lacking. Objectives: Herein, we aimed to determine the frequency and risk of AEs associated with ixazomib in Japanese patients using the Japanese Adverse Event Reporting Database (JADER). Additionally, the time to onset and post hoc outcomes of unique AEs were clarified. Methods: To investigate the association between ixazomib and AEs, we analyzed the JADER database, comprising voluntary AE reports submitted to the Pharmaceuticals and Medical Devices Agency, between April 2004 and June 2021. AEs with ≥10 reports were included in the analysis, and criteria for the presence of AE signals were defined as meeting the requirements of proportional report ratio ≥2 and χ2 ≥ 4. Characteristic AEs were analyzed considering time to onset and onset outcomes. Results: Of 34 extracted AEs, 18 presented AE signals. The 12 post hoc outcomes with fatality rates ≥10% included septic shock (50.0%), infection (41.2%), heart failure (16.7%), pneumonia (14.2%), and tumor necrosis syndrome (13.3%). A median of the time to onset showed that 11 of the 18 AEs occurred from ixazomib initiation to approximately 1 month later. Conclusion: Our results suggest that ixazomib may increase the incidence of 18 AEs, 11 of which occurred within the first month of treatment. Furthermore, 8 AEs were found to have potentially fatal outcomes at a rate of ≥10%. Therefore, monitoring AEs during the first month of treatment appears necessary.