Avelumab First-Line Maintenance for Locally Advanced or Metastatic Urothelial Carcinoma: Results From the Real-World US PATRIOT-II Study

Abstract

INTRODUCTION: In JAVELIN Bladder 100, avelumab first-line maintenance (1LM) improved overall survival (OS) and progression-free survival (PFS) in patients with locally advanced/metastatic urothelial carcinoma (la/mUC) without progression following 1L platinum-based chemotherapy (PBC) versus best supportive care. PATRIOT-II describes real-world outcomes with avelumab 1LM. PATIENTS AND METHODS: This observational, retrospective study of avelumab 1LM in US community/academic centers used medical record data collected from avelumab initiation for ≥12 months to assess survival, safety, and healthcare resource utilization; analyses are descriptive. RESULTS: The study included 160 patients from 37 centers (median age, 70 years; 77% male). Avelumab 1LM was initiated at a median of 4 weeks (IQR 3-6) after PBC completion. Median follow-up from avelumab 1LM was 16 months (IQR 11-21). At study end, 19.4% of patients continued avelumab; 73.7% had discontinued due to progression, adverse events (AEs), or performance status deterioration. Median PFS and OS from avelumab initiation were 5.4 months (95% CI, 3.8-6.9) and 24.4 months (95% CI, 20.4-28.4), respectively. Grade ≥3 treatment-related AEs (TRAEs) occurred in 15 patients (9.4%); 35 (21.9%) had any-grade immune-related AEs, and 23 (14.3%) received high-dose systemic corticosteroids for AEs. Forty-four patients (27.5%) were hospitalized during the avelumab treatment period, of whom 13 (8.1%) were hospitalized due to TRAEs. Limitations of this study include a small sample size, potential selection bias, and missing/unknown data. CONCLUSION: These results align with the JAVELIN Bladder 100 clinical trial and other real-world studies, supporting avelumab 1LM use in patients with la/mUC without progression following 1L PBC.