Avelumab first-line (1L) maintenance plus best supportive care (BSC) versus BSC alone for advanced urothelial carcinoma (UC): Analysis of time to end of next-line therapy in JAVELIN Bladder 100.

Abstract

4525 Background: Avelumab 1L maintenance is approved in various countries for patients (pts) with advanced UC that has not progressed with 1L platinum-based chemotherapy based on significantly prolonged overall survival (OS) seen with avelumab + BSC vs BSC alone in the phase 3 JAVELIN Bladder 100 trial. OS was prolonged despite the more frequent use of subsequent anticancer therapy in the BSC alone arm (42.3% in the avelumab + BSC arm vs 61.7% in the BSC alone arm), most commonly with immune checkpoint inhibitors (6.3% vs 43.7%, respectively). To further characterize the efficacy benefits of avelumab 1L maintenance, we report a post hoc analysis of the time to end of next-line therapy (for any reason) in the randomized trial population. Methods: In JAVELIN Bladder 100 (NCT02603432), eligible pts had unresectable locally advanced or metastatic UC without disease progression with 4 to 6 cycles of 1L gemcitabine + either cisplatin or carboplatin. The primary endpoint was OS from randomization, assessed in 2 populations: all pts and pts with PD-L1+ tumors (Ventana SP263). In this exploratory analysis, time from randomization until end of next-line treatment received after first progression (due to death or discontinuation) was assessed. Results: A total of 700 pts were randomized 1:1 to avelumab 1L maintenance + BSC or BSC alone. Among all randomized pts, time to end of next-line therapy was prolonged in the avelumab + BSC arm vs the BSC alone arm (Table). Time to end of next-line therapy was also longer in the avelumab + BSC arm vs the BSC alone arm in pts with PD-L1+ tumors (n = 358) or PD-L1− tumors (n = 270). Conclusions: Pts who received avelumab 1L maintenance + BSC had prolonged time to end of next-line treatment compared with those who received BSC alone, irrespective of PD-L1 status. These data provide further evidence of the efficacy of a maintenance approach with avelumab in pts with advanced UC that has not progressed with 1L platinum-based chemotherapy. Clinical trial information: NCT02603432. [Table: see text]