PURPOSE A phase II study was conducted to determine the response rate of ixabepilone (BMS-247550, National Cancer Institute (NCI)-supplied agent investigational new drug No. 59,699) in patients with persistent or recurrent endometrial cancer who have progressed despite standard therapy. PATIENTS AND METHODS Eligible patients had recurrent or persistent endometrial cancer and measurable disease. One prior chemotherapeutic regimen, which could have included either paclitaxel or docetaxel, was allowed. Patients received ixabepilone 40 mg/m(2) as a 3-hour infusion on day 1 of a 21-day cycle. Treatment was continued until disease progression or until unacceptable toxicity occurred. Results Fifty-two patients were entered on the study, and 50 of these were eligible. The median age was 64 years (range, 40 to 83 years). Prior treatment included radiation in 21 patients (42%) and hormonal therapy in eight patients (16%). All patients had prior chemotherapy, and 47 (94%) received prior paclitaxel therapy. The overall response rate was 12%; one patient achieved a complete remission (2%), and five achieved partial remission (10%). Stable disease for at least 8 weeks was noted in 30 patients (60%). The median progression-free survival (PFS) was 2.9 months, and the 6-month PFS was 20%. Major grade 3 toxicities were neutropenia (52%), leukopenia (48%), gastrointestinal (24%), neurologic (18%), constitutional (20%), infection (16%), and anemia (14%). CONCLUSION In a cohort of women with advanced or recurrent endometrial cancer who were previously treated with paclitaxel, ixabepilone showed modest activity of limited duration as a second-line agent.