1636P - Health-related quality of life outcomes of androgen receptor pathway inhibitors versus taxanes versus standard of care in metastatic castration-resistant prostate cancer: Results from the ProBio trial

Background

ProBio (NCT03903835) is a biomarker-driven, platform trial in metastatic prostate cancer, evaluating different treatment classes across multiple biomarker signatures against standard-of-care (SOC). Alongside oncological outcomes, health-related quality of life (HRQoL) is a secondary endpoint. Here, we report HRQoL outcomes of androgen receptor pathway inhibitors (ARPI) versus taxanes, SOC in metastatic castration-resistant prostate cancer (mCRPC).

Methods

Patients with mCRPC underwent genomic analysis before randomization to ARPI, taxanes, or SOC (physician’s choice). EORTC QLQ-C30 HRQoL was measured 3-monthly up to 36 months or disease progression. We modeled HRQoL trajectories using Bayesian joint models, considering informative censoring due to progression. For time to deterioration, defined as 10-point decrement, we estimated cause-specific hazard ratios for different HRQoL domains and symptoms based on Bayesian competing risk models.

Results

A total of 134 patients were randomized to ARPI (N=29), taxanes (N=50) and SOC (N=55). Mean (±standard deviation) global health status scores were balanced across groups with scores of 70 (±19), 72 (±23) and 72 (±25), respectively. Until 6 months, the global health improved in the ARPI group and subsequently declined over time. In contrast, immediate decreases in global health were observed in the taxane and SOC groups. Functional domain declines occurred in all groups and, with the exception for cognitive function, were typically more substantial in the taxane group. Role, social, and emotional functioning were better preserved with ARPI compared to taxanes and SOC. Symptom scales were better in ARPI-treated patients, with lower pain levels, especially at time points beyond 12 months. Most symptoms increased over time in all groups. Furthermore, ARPI was associated with a lower deterioration rate in global health status compared to both taxane (HR 0.3, 95% CI: 0.18-0.5) and SOC (HR 0.41, 95% CI: 0.26-0.63).

Conclusions

ARPI-treated mCRPC patients experience an initial improvement in HRQoL and experience overall superior HRQoL compared to those receiving taxanes or SOC.

Clinical trial identification

NCT03903835, EudraCT 2018-002350-78.

Editorial acknowledgement

Legal entity responsible for the study

ProBio Consortium.

Funding

Kom op tegen Kanker, Swedish Research Council, Swedish Cancer Society, Janssen, AstraZeneca.

Disclosure

All authors have declared no conflicts of interest.