Noninterventional retrospective study of standard-of-care systemic treatment patterns and outcomes in US patients with advanced urothelial carcinoma.

Background: First-line platinum-based chemotherapy (1L PBC) followed by avelumab 1L maintenance (1LM) in patients without disease progression after 1L PBC is a standard-of-care treatment in locally advanced/metastatic urothelial carcinoma (la/mUC). We examined real-world treatment patterns and outcomes in patients with la/mUC treated in the US and characterized early adoption of avelumab 1LM following US Food and Drug Administration approval in June 2020.

Materials And Methods: This retrospective cohort study identified patients ≥ 18 years diagnosed with la/mUC between January 2015 and July 2021 using electronic health records from the Flatiron Health database. Treatment patterns and baseline characteristics were described by type of 1L treatment. Real-world progression-free survival (rwPFS) and real-world overall survival (rwOS) were determined using the Kaplan-Meier method.

Results: A total of 4387 patients were included, with 3706 (84.5%) receiving systemic treatment. The most common 1L therapy was cisplatin-based therapy (33.3%), followed by carboplatin-based (30.9%) and immuno-oncology (IO) therapies (28.0%). Patients treated with 1L cisplatin-based therapy had longer median rwPFS and rwOS from 1L initiation (8.0 and 18.3 months, respectively) vs patients treated with 1L carboplatin-based therapy (6.4 and 13.2 months), or IO therapies (6.1 and 14.2 months). Among eligible patients, early use of avelumab 1LM was 29%. Approximately half (51.7%) of treated patients received second-line (2L) treatment, 16.8% received no 2L treatment, and 31.5% remained on 1L at end of study.

Conclusion: Our findings contribute to our understanding of optimal treatment sequencing options based on individual patient characteristics in a rapidly evolving treatment landscape.