Efficacy of platinum re-challenge in metastatic urothelial carcinoma (mUC): A retrospective comparison of chemotherapy regimens.

459 Background: First-line platinum-based combination chemotherapy (fPBC) is standard of care for fit patients with mUC. Further lines of therapy include immuno-oncology agents, erdafitinib, and enfortumab vedotin, but patients ineligible for these therapies or who subsequently progress may be considered for further chemotherapy. As the choice of chemotherapy regimen is unclear for these patients, we compared the efficacy of subsequent...