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). The gene discussed is CD274; the disease is neoplasm.