Avelumab first-line (1L) maintenance treatment in patients with locally advanced or metastatic urothelial carcinoma (la/mUC) in the Czech Republic: Updated real-world results from a national reimbursement registry.
Authors: Hana Studentova, Anežka Zemánková, Bohuslav Melichar, Michal Eid, Alexandr Poprach, Jindřich Kopecký, Tomáš Büchler, Darja Šustrová, Šárka Stuhlová, Jan Dvořák, Zuzana Donátová, Pavel Vlček, Kateřina Zycháčková, Jana Katolicka, Tomáš Blažek, David Vrána, Ondřej Fiala, Petra Májková, Adam Čepa
Journal: Journal of Clinical Oncology (2025)

693 Background: Platinum-based chemotherapy followed by avelumab 1L maintenance treatment for patients with nonprogressive disease is a standard of care in la/mUC. In the Czech Republic, following EU approval, there is a requirement to provide real-world data for “highly innovative medicinal products” and obtaining reimbursement requires registry creation for data collection. Interim results from a retrospective analysis of a national reimbursement registry for avelumab 1L maintenance treatment in the Czech Republic were reported previously; here, we report longer-term results. Methods: Registry data were collected by the Health Insurance Bureau for patients with la/mUC receiving avelumab 1L maintenance treatment between Oct 2021 and Jan 2024. The primary endpoint was overall survival (OS) from start of avelumab 1L maintenance (index date); secondary endpoints included progression-free survival (PFS) and safety. Descriptive statistics were used to analyze the data. OS, PFS, and probability of ongoing response were estimated using the Kaplan-Meier method. Results: Overall, 107 patients with la/mUC were treated with avelumab 1L maintenance (77 male/30 female). 1L platinum-based chemotherapy was cisplatin based in 55 patients (51.4%) and carboplatin based in 46 patients (43.0%); 6 patients (5.6%) switched regimens. At the start of avelumab, median age was 72 years (range, 45-92), and 41 patients (38.3%) had visceral metastases. Median follow-up was 8.2 months (range, 0-26.2). Median duration of avelumab treatment was 9.7 months (range, 1.0-29.2). The table shows effectiveness data for avelumab 1L maintenance. Overall, 16 adverse events were reported in 18 patients (16.8%), including 1 patient with a grade 3 infusion reaction and 2 patients with grade 2 diarrhea. At data cutoff (Jan 31, 2024), 88 patients were alive, and 23 had started subsequent treatment. Conclusions: These updated data are generally consistent with results from the JAVELIN Bladder 100 phase 3 trial and other real-world studies, supporting the effectiveness and favorable safety profile of avelumab as 1L maintenance treatment in patients with la/mUC that has not progressed with 1L platinum-based chemotherapy. N=107 Median OS, months Not reached OS rate, % (95% CI) 6 months12 months18 months 93.4 (88.4-98.7)79.3 (69.8-90.2)68.0 (54.6-84.6) Median PFS, months (95% CI) 11.0 (8.6-not estimable) PFS rate, % (95% CI) 6 months12 months18 months 67.8 (58.7-78.2)48.9 (38.8-61.6)39.1 (27.5-55.4) Objective response rate, n (%) Complete response Partial response 29 (27.1)12 (11.2)17 (15.9) Median duration of response, months Not reached Probability of ongoing response, % (95% CI) 6 months12 months18 months 91.1 (80.0-100)80.4 (64.7-99.8)80.4 (64.7-99.8) Median time to response, months 3.4 (1.8-18.2)