Abiraterone is associated with higher odds of cardiac complications compared to enzalutamide
Cone EB, Modonutti D, Reese S, Marchese M, Nabi J, Abdollah F, Kilbridge K, and Trinh QD. Abiraterone is associated with higher odds of cardiac complications compared to enzalutamide. European Urology Open Science 2020; 19:e880.
European Urology Open Science
Introduction & Objectives: The standard of care for advanced prostate cancer is androgen deprivation therapy (ADT). The novel second generation agents abiraterone and enzalutamide were initially approved in castration resistant disease, but are now being used in the hormone sensitive setting. The FDA issued a 2010 warning about cardiovascular risks associated with ADT, but the risk of novel agents is less well understood, especially in comparison to each other. We sought to define the comparative cardiac risk profile of enzalutamide and abiraterone.
Materials & Methods: We used VigiBase, the World Health Organization database of individual case safety reports, which collects data from more than 130 countries to identify drug associated adverse events (AE). Using Medical Dictionary for Regulatory Activities terminology, we identified cardiac AEs related to abiraterone or enzalutamide therapy for prostate cancer. To explore a possible relationship we used the reporting odds ratio (ROR), a surrogate measure of association using all other reactions as non-cases. A lower bound of a 95% confidence interval of ROR >1 reflects a disproportional signal that more AEs are observed than expected due to chance.
Results: Vigibase contained 8203 AEs for abiraterone and 26024 for enzalutamide; 808 (9.9%) were cardiac-related for abiraterone, and 1000 for enzalutamide (3.8%). We found no disproportional signal for cardiac events or any sub type for enzalutamide, but identified significantly higher odds of overall cardiac events (ROR 1.64, 95% CI 1.53—1.76), myocardial infarction (1.34, 1.17—1.58), arrythmia (2.09, 1.87—2.34), and heart failure (3.35, 2.92—3.85) for patients taking abiraterone.
Conclusions: Using validated pharmacovigilance methodology, we found significantly increased odds of cardiac events for abiraterone but not for enzalutamide. Clinicians may need to consider these findings in the context of their patients’ comorbidities when prescribing ADT.