Exploratory analyses of treatment subgroup interaction by PD-L1 status and according to PD-L1 expression in the JAVELIN Bladder 100 trial

Purpose Post hoc analysis of the JAVELIN Bladder 100 trial of avelumab maintenance in locally advanced/metastatic urothelial carcinoma (la/mUC) to determine the interaction by programmed death ligand 1 (PD-L1) status for overall survival (OS), and additional analyses of survival per a different PD-L1 expression cutoff of ≥ 1% in tumor cells or immune cells (TC/IC). Methods JAVELIN Bladder 100 data were used for the analysis of the interaction by PD-L1 status (per cutoff used in the trial) for OS and, additionally, OS and progression-free survival (PFS) analyses per a different ≥ 1% TC/IC PD-L1 expression cutoff (Ventana SP263 assay). Results No significant interaction between treatment and PD-L1 status was observed for OS. Clinically meaningful and robust survival data were observed in favor of avelumab using the different ≥ 1% TC/IC PD-L1 expression cutoff. Conclusions These results demonstrate the benefit of avelumab maintenance in la/mUC regardless of PD-L1 expression, consistent with approved labels.