New post-hoc analysis from the phase 3 ARASENS trial reveals that darolutamide's benefits in metastatic hormone-sensitive prostate cancer (mHSPC) extend across all age groups, as presented at the 2025 American Society of Clinical Oncology Genitourinary Cancers Symposium.
Age-Specific Outcomes in ARASENS Trial
The analysis, presented by Dr. Joan Carles of Vall d'Hebron Institute of Oncology, examined 1,305 patients ranging from 41 to 89 years old. The study population comprised 1,086 patients under 75 years (83%) and 219 patients aged 75 or older (17%), with balanced baseline characteristics between age groups.
Treatment completion rates remained high across age groups, with 89% of younger patients and 80% of older patients completing the full six cycles of darolutamide therapy. This demonstrates strong treatment adherence regardless of age.
Survival Benefits Across Age Groups
The data showed remarkable consistency in survival benefits:
- Patients under 75: Hazard ratio of 0.70 (95% CI, 0.58-0.84)
- Patients 75 and older: Hazard ratio of 0.61 (95% CI, 0.41-0.91)
These results align with the overall population's hazard ratio of 0.68 (P < .0001), indicating a significant reduction in mortality risk across all age groups.
Disease Progression and Treatment Sequencing
Time to castration-resistant prostate cancer (CRPC) showed significant improvements:
- Under 75 age group: HR 0.35 (95% CI, 0.30-0.43)
- 75 and older group: HR 0.42 (95% CI, 0.28-0.64)
The time to initiation of subsequent systemic therapy was similarly delayed in both age groups, with hazard ratios of 0.40 and 0.35 for younger and older patients, respectively.
Safety Profile Analysis
Treatment-emergent adverse events (TEAEs) showed comparable patterns between darolutamide and placebo groups, though slightly higher frequencies were observed in patients 75 and older. Key findings include:
- Low discontinuation rates due to TEAEs across both age groups
- Higher incidence of grade 3/4 neutropenia and anemia in older patients
- Similar rates of AR pathway inhibitor-associated adverse events between treatment groups
"Patients with metastatic hormone-sensitive prostate cancer benefited from treatment with darolutamide plus ADT and docetaxel regardless of age," concluded Dr. Carles, emphasizing the treatment's consistent efficacy and safety profile across the age spectrum.
Clinical Implications
These findings are particularly significant given the aging population of prostate cancer patients. The demonstrated efficacy and tolerability in older patients support darolutamide's use across age groups, providing clinicians with valuable data for treatment decisions in both younger and elderly patients with mHSPC.
