Sequencing of PD-1/L1 Inhibitors and Carboplatin-Based Chemotherapy for Cisplatin-Ineligible Metastatic Urothelial Carcinoma

Bladder Cancer
16/09/2020

J Urol. 2020 Sep 16:101097JU0000000000001371. doi: 10.1097/JU.0000000000001371. Online ahead of print.

ABSTRACT

PURPOSE: Current first-line treatment options in patients with metastatic urothelial carcinoma (mUC) unfit to receive cisplatin-containing chemotherapy include PD-1/L1 inhibitors and carboplatin-containing chemotherapy. However, the optimal sequencing of these therapies remains unclear.

MATERIAL AND METHODS: We conducted a multicenter retrospective analysis. Consecutive cisplatin-ineligible patients with mUC treated with first-line carboplatin-containing chemotherapy followed sequentially by second-line PD-1/L1 inhibitor, or the reverse order, were included. Patient demographics, objective response, time to treatment failure for first-line (TTF1) and second-line (TTF2) therapy, interval between end of first-line and initiation of second-line treatment (Interval1L-2L), and overall survival (OS) were collected. Multivariate analysis was conducted to examine the association of sequencing on OS.

RESULTS: In this multicenter retrospective study, we identified 146 cisplatin-ineligible patients with mUC treated with first-line (1L) PD-1/L1 inhibitor therapy followed by second-line (2L) carboplatin-containing chemotherapy (Group 1, n=43) or the reverse sequence (Group 2, n=103). In the overall cohort, median age was 72, 76% were men, and 18% had liver metastasis. In both groups, objective response rates were higher with carboplatin-containing chemotherapy (45.6% 1L, 44.2% 2L) compared to PD-1/L1 inhibitors (9.3% 1L, 21.3% 2L). On multivariate analysis, treatment sequence was not associated with overall survival (HR 1.05, p=0.85). Site of metastasis was the only factor significantly associated with overall survival (p=0.002).

CONCLUSIONS: In this biomarker-unselected cohort of cisplatin-ineligible patients with mUC, PD-1/L1 inhibitor followed by carboplatin-containing chemotherapy and the reverse sequence had comparable OS.