First-line PD-1/PD-L1 inhibitor followed by carboplatin (carbo)-based chemotherapy (chemo) or the reverse sequence in cisplatin-ineligible metastatic urothelial cancer (mUC) patients (pts)

e16517Background: PD-1/PD-L1 inhibitors or carbo-based chemo are both reasonable therapeutic options in the first-line setting for cisplatin-ineligible mUC pts. However, optimal first-line therapy and sequencing of these regimens is unclear. Methods: We conducted a multicenter retrospective analysis of cisplatin-ineligible mUC pts treated with first-line PD-1/PD-L1 monotherapy followed by carbo-based chemo (P- > C) or the reverse order (C- > P). Perioperative cisplatin-based chemo was allowed if the interval between its completion and starting first-line mUC therapy was > 1 year. A multivariate analysis (MVA) examined the association of sequence of therapy with overall survival (OS) adjusted for baseline Hb ( C n = 33, C- > P n = 82) with median age 71, 74% men, and 85% ECOG PS 0-1 were included. Most pts (94.8%) had not received prior perioperative cisplatin-based chemo,...