A phase II study of single agent abraxane as second-line therapy in patients with advanced urothelial carcinoma

e16058 Background: Metastatic urothelial cancer progressing on or after first-line platinum-based chemotherapy is incurable and has a very poor prognosis. There is no standard second-line therapy, but the taxanes including paclitaxel, have previously shown activity. Abraxane (ABI-007) is a novel well tolerated albumin-bound nanoparticle formulation of paclitaxel. The goal of this study was to determine the efficacy and tolerability of single agent Abraxane in the second-line metastatic urothelial cancer setting. Methods: Patients with measureable metastatic urothelial cancer, who progressed on or after first-line cisplatin based chemotherapy were enrolled onto this phase II, two-stage multicenter trial. Patients received Abraxane 260 mg/m 2 intravenously every 3 weeks. Clinical evaluation, CBC and blood chemistries were performed every cycle and restaging CT scans every 2 cycles. Results: Fourteen patients have been enrolled to date. Patient demographics: M: F 12:2; mean age 64 (range 45–80); ECOG 0:1:2 4:5:5. A total of 57 cycles, avg 4 cycles/ patient (range 1–9) have been administered. There were three dose delays due to neuropathy, pain, and low neutrophil count respectively. There were two dose reductions due to fatigue and neuropathy. Most frequent adverse events (AE) were fatigue, alopecia, anorexia, cough and joint pain; the most frequent grade 3+ AE were fatigue, joint pain, hypertension, joint stiffness and back pain. Fourteen patients are currently evaluable for best response using RECIST criteria. There have been 5 partial responses (PR), 5 stable disease (SD) and 4 progressive disease (PD). Conclusions: Single agent Abraxane was well tolerated in the 2 nd line, cisplatin refractory/resistant metastatic urothelial cancer setting. Preliminary efficacy results are encouraging with a clinical benefit rate of 71% (10 out of 14 evaluable pts having either SD or PR). Stage 1 response criteria have been met and accrual is ongoing to a total of 48 patients. No significant financial relationships to disclose.