Efficacy and Safety of Enzalutamide and Abiraterone Plus Prednisolone in Elder Castration-Resistant Prostate Cancer

Takehiko Okamura1, Kouji Izumi2, Satoshi Kurokawa1

  • 1Department of Urology, Anjo Kosei Hospital, Anjo, Aichi, Japan.

The Prostate
|April 4, 2025
PubMed
Abstract

Insights

Second-generation androgen receptor signaling inhibitors (ARSIs) show similar efficacy and safety in older and younger patients with castration-resistant prostate cancer. Enzalutamide may be a better choice for elderly individuals.

Area of Science:

  • Oncology
  • Urology
  • Clinical Pharmacology

Background:

  • Limited clinical trial data exists for elderly patients with castration-resistant prostate cancer (CRPC).
  • Outcomes of second-generation androgen receptor signaling inhibitors (ARSIs) in older CRPC patients are not well-documented.

Purpose of the Study:

  • To compare the efficacy and safety of enzalutamide (ENZ) and abiraterone plus prednisolone (ABI) in older versus younger patients with CRPC.
  • To analyze treatment outcomes within older and younger cohorts separately for ENZ and ABI.

Main Methods:

  • Sub-analysis of the multicenter, randomized controlled ENABLE study conducted in Japan.
  • Patients were stratified into two groups: aged ≥75 years (older) and <75 years (younger).
  • Efficacy endpoints included time to prostate-specific antigen (PSA) progression (TTPP) and overall survival (OS); safety was assessed via adverse events.

Main Results:

  • No significant differences in survival endpoints (TTPP, OS) were observed between younger and older patients.
  • Among older patients, enzalutamide showed a trend towards longer TTPP (21.2 vs. 10.1 months) and OS (37.8 vs. 44.7 months) compared to abiraterone, though not statistically significant.
  • Adverse event rates were similar between younger and older patients, and between treatment arms.

Conclusions:

  • Androgen receptor signaling inhibitors (ARSIs) exhibit comparable efficacy and safety profiles in both younger and older patients with CRPC.
  • Enzalutamide (ENZ) may represent a more favorable treatment option for elderly CRPC patients, potentially due to higher PSA response rates.