Proteasome inhibitor associated cardiovascular adverse events: A real-world claims based study

e19534 Background: Cardiovascular adverse events (CVAE) are common in patients with multiple myeloma (MM). Recent evidence suggests higher rates of CVAE occur among patients receiving carfilzomib (CFZ) compared to other MM therapies. We sought to determine the real-world relative incidence of CVAE in patients receiving CFZ and bortezomib (BTZ). Methods: We conducted a retrospective cohort study using the Optum Clinformatics Datamart. Patients with MM were included if they received BTZ or CFZ from 2012 to 2016. Exposure periods were defined as 90 days following infusion of either drug. Cardiac hospitalizations were identified using validated ICD-9 or ICD-10 code algorithms for heart failure, arrhythmia, myocardial infarction, and hypertensive urgency. Incidence rate ratios (IRR) were calculated using Poisson regression. Results: We identified 922 patients receiving CFZ and 4092 patients receiving BTZ (median age 70 and 72; median treatment duration 99 and 107 days; concurrent immunomodulatory drugs received in 28% and 25%, respectively). Unadjusted CVAE rates are summarized below. A multivariable regression model showed age (IRR 1.43, 95% CI 1.33-1.55) and male gender (IRR 1.22, 95% CI 1.07-1.40) were independent risk factors for CVAE while concurrent IMiD prescription was associated with lower risk (IRR 0.70, 95% CI 0.58-0.85). Adjusted CVAE rates were similar for patients treated with CFZ and BTZ (IRR 1.06, 95% CI 0.89-1.27). Conclusions: We found higher rates of CVAE hospitalizations than described in clinical trials. This may reflect differences in real-world treatment, patient selection patterns, or later identification of CVAE. Further study is need to identify patients at high-risk of CVAE and to develop risk reduction strategies. [Table: see text]