Would you use maintenance avelumab for a patient with metastatic urothelial carcinoma who progressed on first-line pembrolizumab, then had stable disease after at least four cycles of second-line carboplatin plus gemcitabine?  

Great question. I would suggest that if the patient progressed on prior PD-1/PD-L1 inhibition, the standard would be observation (as challenging as that may be in clinical practice!). At progression, would probably not offer checkpoint inhibitor and would instead favor novel therapies like enfortuma...