Real-world data of atezolizumab in patients with previously treated locally advanced or metastatic urothelial bladder cancer.

Abstract

Clinical trials of atezolizumab for locally advanced or metastatic urothelial bladder cancer (mUBC) report controversial efficacy data. Furthermore, real-world evidence about this use is limited. We aimed to evaluate the effectiveness of atezolizumab in a real-world population with mUBC, to explore effectiveness withregard to selected poor prognostic criteria such as performance status by Eastern Oncology Cooperative Group (ECOG), hemoglobin levels and liver metastases, and to determine the safety profile of atezolizumab. Multicenter, retrospective real-world study including previously treated mUBC patients who received atezolizumab. The primary endpoint was overall survival (OS). Additionally, progression-free survival (PFS), best response reached and safety data were analyzed. A descriptive analysis was performed, while OS and PFS were estimated by Kaplan-Meier method. A total of 185 patients (84.9% men, median age 69years) were included. Median PFS was 4.8months [95% confidence interval (CI) 3.6-6.0], and median OS was 20.0months (95% CI 11.8-28.5), with an objective response rate of 28.1%. OS was higher for patients with ECOG 0-1 versus 2-3 [24.5months (95% CI 14.5-34.6) vs. 5.2 (95% CI 4.4-6.0), p = 0.004]; and for patients without liver metastases [25.4months (95% CI 16.2-34.6) vs. 6.4months (95% CI 4.0-8.1), p = 0.006]. Regarding hemoglobin levels, no survival differences were detected. Adverse events were registered in 55.1% of patients. In a real-world population with previously treated mUBC, atezolizumab seems to provide clinically relevant benefit, which is even higher for patients with ECOG 0-1 and without liver metastases, with an acceptable safety profile.