(UroToday.com) Avelumab first-line maintenance is approved in various countries for patients with advanced urothelial carcinoma that has not progressed with first-line platinum-based chemotherapy based on significantly prolonged overall survival (OS) seen with avelumab + best supportive care versus best supportive care alone in the phase 3 JAVELIN Bladder 100 trial (HR 0.69, 95% CI 0.56 to 0.86; 1-sided p = 0.0005).1 In the trial, OS was prolonged despite the more frequent use of subsequent anticancer therapy in the best supportive care alone arm (42.3% in the avelumab + best supportive care arm vs 61.7% in the best supportive care alone arm), most commonly with immune checkpoint inhibitors (6.3% vs 43.7%, respectively). To further characterize the efficacy benefits of avelumab first-line maintenance, at the 2021 ASCO annual meeting Dr. Petros Grivas and colleagues reported results of a post hoc analysis of time to end of next-line therapy (for any reason) in the randomized trial population.