Immunotherapy Combinations and Sequences in Urothelial Cancer: Facts and Hopes.

Immune checkpoint inhibitors (ICI) have emerged as a novel therapeutic strategy that achieves significant clinical benefit in several tumor types, including urothelial cancer. Overall, these agents have shown objective response rates of around 20% to 23%, which indicates that a significant proportion of patients do not benefit from immunotherapy when given as monotherapy. Moreover, despite an initial response to therapy and an improvement in the median duration of response compared with chemotherapy, still only half of the patients develop long-term maintained remissions. Active research is ongoing in several fields, aiming to increase the number of patients that benefit from ICI, and this research is largely based on the development of biomarkers for personalized immunotherapy and novel combinations of ICI with other agents. This article will review ongoing efforts to develop combinations of ICI with other therapeutic strategies in patients with urothelial cancer, including chemotherapy, targeted agents, other immunotherapy strategies, and radiotherapy. ©2018 American Association for Cancer Research.