A phase III, randomized, open-label, multicenter, global study of first-line (1L) durvalumab in combination with standard of care (SoC) chemotherapy and durvalumab in combination with tremelimumab and soc chemotherapy versus soc chemotherapy alone in patients with unresectable locally advanced or metastatic urothelial cancer (UC).

TPS499Background: Despite high response rates to 1L SoC for locally advanced or metastatic UC chemotherapy (gemcitabine +cisplatin or gemcitabine + carboplatin for patients who are cisplatin-ineligible [poor performance status, impaired renal function, comorbidities]), most patients experience disease progression. Novel strategies like combining chemotherapy and immunotherapy offer hope for improving clinical outcomes. Durvalumab is a selective, high affinity, engineered human IgG1 mAb that blocks PD-L1 binding to PD-1 and CD80. Tremelimumab is a human IgG2 mAb directed against CTLA-4. The mechanisms of action of PD-1 and CTLA-4 are nonredundant, so targeting both checkpoint pathways may have additive or synergistic efficacy compared to monotherapy. Studies in other tumor types of platinum-based chemotherapy combined with checkpoint blockade have yielded improved efficacy with acceptable safety and support exploration of this approach for 1L locally advanced or metastatic UC. Methods: NILE is a randomized...