Safety differences across androgen receptor inhibitors in nonmetastatic castration-resistant prostate cancer

Approval of apalutamide, enzalutamide and darolutamide has transformed the treatment landscape and guideline recommendations for patients with nonmetastatic castration-resistant prostate cancer but now raises the issue of decision-making regarding treatment selection. In this perspective, we discuss the efficacy and safety of these second-generation androgen receptor inhibitors and propose that for patients with nonmetastatic castration-resistant prostate cancer, safety considerations for these treatments are especially important. We examine these considerations in the context of patient and caregiver preferences as well as patient clinical characteristics. We further posit that consideration of treatments’ safety profiles should include not only the initial direct impacts from potential treatment-emergent adverse events and drug–drug interaction events, but also the full cascade of potentially avoidable healthcare complications. Prostate cancer is one of the most common cancers in men. Because male hormones fuel the growth of prostate cancer cells, initial treatments generally focus on reducing these hormones to very low levels. Although these treatments are usually effective in controlling the cancer in the short term, over time, patients often stop responding to them. These patients need more advanced treatments to control their prostate cancer. For patients whose cancer has not spread to other body parts (‘nonmetastatic castration-resistant prostate cancer’), more advanced treatment options were unavailable until recently, but during 2018–2019, three novel therapies became available. These new therapies have raised the question of how to choose a particular therapy when deciding on a patient’s treatment regimen. Here we contend that patient safety is critical when deciding among these treatments, which are all similarly effective in terms of helping patients to live longer. We review the key differences of each drug’s safety profile among these treatments. We assert that treatment selection should consider patients’ preferences and clinical characteristics, as the latter can influence the potential for serious harm when treatment-related complications arise. Finally, treatment selection should consider the multiple after-effects that can occur following a treatment-related safety event. Key safety differences exist among second-generation androgen receptor inhibitors for nonmetastatic castration-resistant prostate cancer. We discuss these differences a