745P Patient-reported outcomes (PROs) from JAVELIN Bladder 100: Avelumab first-line (1L) maintenance + best supportive care (BSC) vs BSC alone for advanced urothelial carcinoma (UC)

Abstract

In the phase III JAVELIN Bladder 100 trial (NCT02603432), avelumab (anti–PD-L1) 1L maintenance + BSC significantly prolonged overall survival (primary endpoint) vs BSC alone in patients (pts) with advanced UC without disease progression with 1L induction chemotherapy. Here we report PRO findings. In JAVELIN Bladder 100, PROs were a secondary endpoint. Pts were assessed at baseline, on day 1 of each 4-week cycle, at the end of treatment/withdrawal visit, and at short-term follow-up visits (up to 90 days post treatment). Two PRO instruments were employed: National Comprehensive Cancer Network – Functional Assessment of Cancer Therapy Bladder Cancer Symptom Index-18 (FBlSI-18) and EuroQol 5 Dimensions 5 Levels (EQ-5D-5L). Descriptive, mixed-model, and time-to-deterioration (TTD; ≥3-point decrease from baseline in the FBlSI disease-related symptoms–physical subscale for 2 consecutive assessments using the Kaplan-Meier method) analyses were conducted in both primary populations: all randomized pts and pts with PD-L1+ tumors. Among all randomized pts in the avelumab + BSC (n=350) and BSC alone (n=350) arms, completion rates for both PRO instruments were >90% for the majority of the treatment period. Results from the descriptive analysis and mixed models over the treatment period in FBlSI-18 and EQ-5D-5L were similar between arms. The hazard ratio for TTD was 1.26 (95% CI, 0.90, 1.77; 1-sided p=0.91); median TTD was not reached (95% CI, 13.9 months, not estimable) with avelumab + BSC and was 13.8 months (95% CI, 12.9 months, not estimable) with BSC alone. However, the TTD results should be interpreted with caution given that death and progression were not included in the event definition, and starting from cycle 2 substantially fewer patients were eligible to complete PROs with BSC alone (n=155) than with avelumab + BSC (n=206). PRO results were consistent in the PD-L1+ population. Adding avelumab 1L maintenance therapy to BSC in pts with advanced UC whose disease had not progressed with 1L platinum-based chemotherapy had no detrimental effect on clinically relevant PROs.