Analysis of the efficacy and safety of avelumab maintenance therapy in subgroups of patients with metastatic urothelial carcinoma in real-world practice (RAVE-Bladder study)

Objective: To evaluate the efficacy and safety of avelumab maintenance therapy in patients with metastatic urothelial carcinoma (UC) in real-world practice.Methods: This ambispective study included patients with metastatic UC and measurable tumor lesions, without progression during and after first-line platinum-based chemotherapy (CHT), who received avelumab maintenance therapy (800 mg IV every 2 weeks). The primary endpoint of the study was overall survival (OS).Results: The study included 110 patients, with a predominance of men (81 %). The median age of all patients was 65 (range, 36-84) years. With a median follow-up of 11.9 months, the median OS was not reached; the one-year OS was 78.7 %. The median progression-free survival (PFS) was 9.5 months (95 % CI, 7.8-11.2 months). The objective response rate (ORR) to first-line chemotherapy was 48.2 %. Of the 97 patients with an evaluated objective response, 38 (39.2 %) demonstrated additional objective responses to avelumab therapy (16 complete and 22 partial responses). Grade 3 adverse events during avelumab therapy were observed in 11.8 % of patients.Conclusions: The efficacy and safety of avelumab maintenance therapy in real-world practice are comparable to those in the pivotal study.