337MO - Efficacy and safety of rezvilutamide (Rez) plus androgen-deprivation therapy (ADT) in patients with high-volume, metastatic, hormone-sensitive prostate cancer (mHSPC) aged ≤64, 65–74, and ≥75 years: Post-hoc analysis of randomized phase III CHART trial

Background

The CHART trial demonstrated that Rez + ADT significantly improved radiographic PFS (rPFS) and OS compared with bicalutamide (Bic) + ADT in high-volume mHSPC (Gu et al., Lancet Oncol, 2022). This post-hoc analysis evaluated the efficacy and safety of Rez + ADT vs Bic + ADT across different age groups.

Methods

Male patients aged ≥18 years with high-volume mHSPC and no prior chemotherapy or other localized treatment for prostate cancer were randomized 1:1 to receive either Rez (240 mg) + ADT or Bic (50 mg) + ADT orally once daily. The efficacy and safety between Rez + ADT and Bic + ADT groups were then compared in subgroups of patients aged ≤64, 65–74, and ≥75 years old.

Results

The study enrolled 654 patients, with 173, 307, and 174 patients in the ≤64, 65–74, and ≥75 age groups, respectively. Baseline characteristics were generally similar among age groups, except for a lower proportion of patients with ECOG PS of 1 in the ≤64 age group (64.2%) compared to the other two groups (65–74 years, 73.6%; ≥75 years, 83.9%). Rez + ADT was superior to Bic + ADT in all three age groups, as evidenced by improvements in OS, rPFS, time to PSA progression, and PSA undetectable rate (Table). The safety profiles of Rez + ADT and Bic + ADT were generally similar in the three age groups. Even in older patients with poor health status (≥75 years and ECOG PS of 1), Rez + ADT demonstrated significantly longer OS (median NE [95% CI 33.3–NE] vs NE [24.5–NE]; HR 0.77 [0.46–1.29]) and rPFS (median NE [95% CI 25.8–NE] vs 25.1 [14.7–NE]; HR 0.65 [0.37–1.12]) compared to Bic + ADT, with similar incidences of treatment-related adverse events in both groups Table: 337MO

Between-group comparisons in efficacy

*Data are HR (95% CI). HR <1 favors Rez + ADT; HR >1 favors Bic + ADT.#Data are % (95% CI). The between-group difference was calculated as the PSA undetectable rate of Rez+ADT minus Bic+ADT.

Conclusions

Rez + ADT was effective and well-tolerated in patients with mHSPC across all age groups, supporting its use as a treatment option for high-volume mHSPC, regardless of age.

Clinical trial identification

NCT03520478.

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Jiangsu Hengrui Pharmaceuticals Co., Ltd.

Disclosure

X. Yang, F. Lian, W. Wang: Financial Interests, Personal, Full or part-time Employment: Jiangsu Hengrui Pharmaceuticals Co., Ltd. All other authors have declared no conflicts of interest.