Pharmacovigilance study for the identification of mogamulizumab-induced immune-related adverse events using a real-world database

Background: Mogamulizumab is a humanized anti-CCR4 monoclonal antibody used for relapsed/refractory adult T-cell leukemia, cutaneous T-cell lymphoma, and/or Sézary syndrome. Reports of immune-related adverse events (irAEs) in these patients are increasing, and the association between irAEs and mogamulizumab remains to be elucidated. This study aimed to evaluate the association between mogamulizumab and immune-related adverse events (irAEs), as well as to characterize the irAEs associated with mogamulizumab using data from a large-scale spontaneous reporting system.
Methods: We performed an exploratory hypothesis-generating analysis of patients from 1967 to September 2023 using VigiBase, a World Health Organization spontaneous adverse event reporting system database. We performed a disproportionality analysis and determined the reporting odds ratios and information components between the drugs of interest and each irAE.
Results: Mogamulizumab was associated with some irAEs, including myocarditis, severe cutaneous adverse reactions, hepatitis, and myositis. Mogamulizumab exhibited significantly higher reporting rates of these 4 irAEs compared to the anticancer agents other than mogamulizumab. Conversely, the reporting rate of other irAEs, including endocrine autoimmune diseases induced by immune checkpoint inhibitors, was not significant in patients who received mogamulizumab.
Conclusions: Mogamulizumab is associated with irAEs, including myocarditis, severe cutaneous adverse reactions, hepatitis, and myositis.