Novel hormonal agents for metastatic Castration-Resistant Prostate Cancer: comparing outcomes. A single-center retrospective study

Abstract

Introduction: Prostate cancer is the most common cancer in men, accounting for 15% of all diagnosed cancers and is the sixth leading cause of cancerrelated deaths amongst men worldwide. Abiraterone and enzalutamide were the first two novel hormonal agents approved for the treatment of metastatic prostate cancer but there is a lack of quality evidence regarding which is associated with better outcomes and who would benefit the most with one or another of these drugs. Objective: To evaluate the clinical outcomes of real-world patients submitted to treatment with novel hormonal agents, enzalutamide and abiraterone, for castration resistant metastatic prostate cancer in an academic center.Patients and methods: We retrospectively reviewed patients treated for castration-resistant prostate cancer with either abiraterone or enzulatamide between January 1, 2016 and December 31, 2019. The primary endpoints were biochemical response, biochemical progression, radiological progression, clinical deterioration (attributed to disease progression) and death. Results: Enzalutamide had a higher biochemical response rate than abiraterone in patients with mCRPC (77.1% vs 58.1%, p = 0.016). Achieving a biochemical response was associated with a lower risk of biochemical progression (OR: 0.248, p = 0.017) and death (OR: 0.302, p = 0.038). Conclusions: Enzalutamide conferred higher biochemical response rate than abiraterone in patients with mCRPC. Despite the trend to better performance of other endpoints in the enzalutamide group, it did not achieve statistical significance. Well-designed prospective studies are needed to elucidate the comparative efficacies of these agents.

Outcomes Following Abiraterone versus Enzalutamide for Prostate Cancer: A Scoping Review

“…Better mCRPC response to ENZ was widely observed, although concomitant survival benefit was only occasionally found. Jarimba et al demonstrated higher response rates with ENZ versus AA (77.1% vs. 58.1%, p = 0.016) and showed that positive response independently reduced risk of both biochemical progression (OR: 0.248, p = 0.017) and death (OR: 0.302, p = 0.038), but still found no significant difference in all-cause time to death (37.5 months ENZ vs. 26 months AA, p = 0.277) [ 2 ]. Higher PSA response with ENZ (61.6% vs. 43.8%, p < 0.004) and greater time to progression (HR 0.66; 95% CI 0.50–0.88, p < 0.01) were recorded by Soleimani et al [ 28 ].…”

“…We reviewed included articles to uncover trends in ADEs and differences in common types of toxicities between AA and ENZ, along with associations with patient co-morbidities. Jarimba et al reported ADEs in 16.1% of AA and 11.4% of ENZ patients, while Chowdhury et al found that 7.1% of AA and 13.5% of ENZ patients discontinued treatment due to toxicity, and death during the treatment period was seen in 7.2% of AA and 11.1% of ENZ patients [ 2 , 38 ].…”

“…Central nervous system (CNS) toxicities including amnesia, cognitive disorders, confusion, and memory impairment; fatigue; and hot flashes were more common in patients treated with ENZ [ 2 , 15 , 41 ]. Specifically, one study identified more frequent fatigue in ENZ versus AA (18% vs. 4%, p = 0.04) [ 42 ], and another demonstrated that fatigue was the most common reason for ENZ dose reductions (30.4%) or discontinuation (5.6%) [ 28 ].…”

“…Prostate cancer (PCa) is the most commonly diagnosed non-skin cancer in men, accounting for over 20% of new cancer cases [ 1 , 2 , 3 , 4 ]. Abiraterone acetate (AA), an androgen biosynthesis inhibitor, and enzalutamide (ENZ), an androgen receptor signaling inhibitor, are novel hormonal therapies (NHTs) that are mainstay additions to androgen deprivation therapy in PCa, particularly in metastatic disease [ 5 , 6 , 7 , 8 , 9 , 10 ].…”

“…By understanding real-world outcomes based on disease-specific measures, drug-associated toxicities, patient comorbidities, and broader systemic factors, clinicians can perform an informed risk assessment to guide treatment choice and optimize the patient experience. Notably, AA and ENZ have primarily been compared in small, retrospective cohorts, which are limited in interpretation but offer real-world data, the compilation of which may offer great clinical insight [ 2 ].…”