Five new PD-1/PD-L1 checkpoint inhibitors have been approved for the treatment 
of metastatic urothelial carcinoma (UC): pembrolizumab, atezolizumab, 
durvalumab, nivolumab, and avelumab. Although cisplatin-based chemotherapy 
remains the recommended frontline option for cisplatin-eligible patients with 
metastatic UC, immunotherapy is now an available option in the second-line 
setting as well as the frontline setting for selected cisplatin-ineligible 
patients who are either unable to tolerate chemotherapy or PD-L1-positive. This 
review describes the updated clinical efficacy of these checkpoint inhibitors in 
the treatment of advanced UC and suggests how they can be sequenced in the 
context of available chemotherapeutic options.