A Multicenter, Single-Arm, Prospective Trial to Evaluate Efficacy and Safety of Dose-Dense Methotrexate, Vinblastine, Doxorubicin, and Carboplatin (DD-MVACarbo) Chemotherapy for Cisplatin-Ineligible Patients with Advanced Urothelial Cancer: Study Protocol of the CARBUNCLE Trial.

Unresectable, metastatic, advanced urothelial carcinoma (aUC) is an aggressive disease and is treated with platinum-containing first-line chemotherapy, followed by immune checkpoint inhibitors and antibody-drug conjugates. Response to first-line chemotherapy is a vital priority in sequential treatment strategies because a better response to first-line chemotherapy is associated with a better response to subsequent therapies. Gemcitabine plus carboplatin chemotherapy is conventionally recommended for cisplatin-ineligible patients. This multicenter, single-arm prospective trial will investigate whether dose-dense methotrexate, vinblastine, doxorubicin, and carboplatin (DD-MVACarbo) chemotherapy is superior to gemcitabine plus carboplatin chemotherapy in terms of efficacy in platinum-naïve, cisplatin-ineligible patients with aUC. After screening and registration, a total of 46 patients will be treated with this novel chemotherapy regimen. The primary endpoint is the objective response rate. The secondary endpoints include disease control rate, patient-reported outcomes, and adverse events. No evidence of this novel intervention is available as of July 2024. The results are expected to change the standard of care and improve the management of patients with aUC.