Real-world efficacy and sequential therapy patterns after avelumab maintenance in metastatic urothelial carcinoma: a Brazilian multicenter retrospective cohort study

Introduction

Avelumab is approved as maintenance therapy after platinum-based chemotherapy in metastatic urothelial carcinoma (mUC). Real-world evidence is needed to validate outcomes and define its role in the era of newly approved agents. Patients and methods: This retrospective study included patients with mUC from a Brazilian multicenter oncology network (2021–2026) who received ≥1 cycle of avelumab following chemotherapy. The primary endpoint was overall survival (OS), defined as the time from avelumab initiation to death from any cause. Secondary endpoints included progression-free survival (PFS), treatment-related toxicity, and subsequent therapies after progression. Survival outcomes were estimated using the Kaplan–Meier method.