A multicenter phase II study of cisplatin (C), gemcitabine (G), and bevacizumab (B) as first-line chemotherapy for metastatic urothelial carcinoma (UC): Hoosier Oncology Group GU-0475.

5018 Background: Despite CG therapy, most metastatic UC patients die from their disease. Novel approaches are needed. Combining anti-angiogenic therapy with chemotherapy has improved outcomes in other malignancies, offering hope for similar improvements in UC patients. METHODS Metastatic or unresectable chemonaive UC patients (pts) with an ECOG performance status of 0-1 received C 70 mg/m2 iv d1, G 1,000-1,250 mg/m2 iv d1, 8, and B 15 mg/kg iv d1 on a q21d cycle for up to 8 cycles. Gemcitabine was reduced to 1,000 mg/m2 iv d1, 8 for all subsequent pts after 7 thromboembolic events were noted in the first 17 pts. The primary endpoint was progression free survival (PFS). The trial was designed to detect a 33% improvement in PFS from 7.5 months with traditional CG therapy to 11.25 months with CGB. RESULTS By December 2008, 45 pts were enrolled, with 43 evaluable for toxicity, 36 for response. Demographics include: 33 (77%) male, 10 (23%) female; median age 66 (Range: 41 - 78); 26 (60%) and 17 (40%) ECOG 0/1; 19 (44%) and 24 (56%) lymph node only / visceral metastases. PFS will be evaluated in May 2009 when all pts will have more than 6 month follow-up data. 14 (33%) and 6 (14%) pts experienced grade 3 or 4 hematologic toxicity (4 pts - thrombocytopenia, 2 pts - neutropenic fever). Grade 3 or 4 nonhematologic toxicity was observed in 24 (56%) and 9 (21%) pts (DVT/PE - 9 pts, CNS hemorrhage/proteinuria/hypertension - 1 pt each) Best RECIST response was: complete response 6 pts (17%, 95% CI 6-33%), partial response 18 pts (50%, 95% CI 33-67%); with overall response rate of 67% (95% CI 51-82%). Stable disease lasting at least 12 weeks was observed in 10 pts (28%, 95% CI 14-45%) and progressive disease in 2 pts (5%, 95% CI 1-19%). CONCLUSIONS CGB demonstrates significant clinical activity in the first-line treatment of metastatic UC patients at the expense of considerable toxicity. The durability of disease control will be determined by assessment of PFS. A phase III trial to further define the toxicity risk vs. clinical benefit of bevacizumab addition to platinum-based doublets is planned in this population. [Table: see text].