A combination study to assess whether 6 in combination with standard of care therapeutics improvesprogression-freesurvival, in comparison to standard of chemotherapy as a monotherapyin patients with metastatic urothelial cancer. Furthermore, this studyseeks to compare overall survival, tumor response rate, and safetybetween the two study arms. Lastly, to assess the role of p53 in predictingresponse to 6. Here, TP53 is linked to neoplasm.