Predictors of abemaciclib discontinuation in patients with breast cancer: a multicenter retrospective cohort study

This study explored the predictors of abemaciclib discontinuation, a cyclin-dependent kinase 4 and 6 inhibitor, in patients with breast cancer. Between November 2018 and March 2023, 147 patients with breast cancer treated with abemaciclib at Osaka Medical and Pharmaceutical University Hospital and Kindai University Nara Hospital were included. The exclusion criteria were as follows: lack of blood testing within 2 weeks prior to starting abemaciclib therapy, transfer to another facility after the commencement of abemaciclib therapy, and discontinuation of abemaciclib therapy due to the diagnosis of another cancer. The duration from the initiation of abemaciclib to discontinuation for any reason and to temporary suspension or dose reduction due to adverse events were analyzed as outcome variables using multivariate Cox regression analysis. Baseline weight