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

Abstract

Background Clinical trials of atezolizumab for locally advanced or metastatic urothelial bladder cancer (mUBC) report controversial efficacy data. Moreover, real-world evidence regarding this use is limited. Aim We aimed to evaluate the effectiveness of atezolizumab in a real-world population with mUBC, to explore the effectiveness in relation to certain 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. Methods This multicenter, retrospective real-world study included previously treated mUBC patients who received atezolizumab. The primary endpoint was overall survival (OS). Furthermore, progression-free survival (PFS), the best response reached, and safety data were analyzed. A descriptive analysis was performed, while OS and PFS were estimated using the Kaplan-Meier method. Results 185 patients (84.9% men, median age 69 years) were included. Median PFS was 4.8 months [95% confidence interval (CI) 3.6-6.0], and median OS was 20.0 months (95% CI 11.8–28.5), with an objective response rate of 28.1%. OS was higher for patients with ECOG 0–1 [24.5 months (95% CI 14.5–34.6) vs 5.2 (95% CI 4.4-6.0), p = 0.004]; and for patients without liver metastases [25.4 months (95% CI 16.2–34.6) vs 6.4 months (95% CI 4.0-8.1), p = 0.006]. Regarding hemoglobin levels, no survival differences were detected. Adverse events were reported in 55.1% of patients. Conclusion In a real-world population with previously treated mUBC, atezolizumab appears to provide a clinically relevant benefit, which is even greater for patients with ECOG 0–1 and those without liver metastases, maintaining an acceptable safety profile.