The Phase III THOR study (NCT03390504) is investigating erdafitinib compared with vinflunine or docetaxel or pembrolizumab in patients with metastatic or surgically unresectable urothelial carcinoma and selected FGFR gene alterations. We spoke to Arlene Siefker-Radtke, MD of the University of Texas MD Anderson Cancer Center, Houston, TX, about this study and its progress. This interview took place at the 2019 Genitourinary Cancers Symposium, held in San Francisco, CA.