Phase Ii Clinical Studies Of Utd1, An Epothilone Analog, In Metastatic Breast Cancer

1040 Background: UTD1, a genetically engineered epothilone analog, is a microtubule stabilizing agent that showed promising activities in phase I trials. In this report, two open-label, multicenter phase II studies of UTD1 alone or UTD1 plus capecitabine (CAP) were carried out to evaluate its efficacy and safety in metastatic breast cancer (MBC) patients (pts). Methods: In both studies, MBC patient who was pretreated with taxanes, anthracyclines and/or CAP received UTD1 at a dose of 40mg/m2/d intravenously on day 1 to day 5 or at 30mg/m2/d (d1-d5) in combination with CAP (2000mg/m2/d, orally) on d1-d14, every 21 days until disease progression or unacceptable toxicity occurred for a maximum of 6 cycles. The primary endpoint was objective response rate (ORR) and the secondary endpoints were toxicity and progression-free survival (PFS) for the combination. Results: 25 pts received a total of 128 cycles in the combination with a median of 6 cycles (range 1-6 cycles) per patient. Among 24 pts who were evaluabl...