Phase II study of LU 103793 (dolastatin analogue) in patients with metastatic breast cancer.

LU 103793 is a synthetic analogue of Dolastatin 15 that inhibits tubulin polymerisation. The aim of this study was to evaluate the efficacy and tolerability of LU 103793 in patients with metastatic breast cancer who had been previously treated with two lines of chemotherapy for advanced disease. Patients received LU 103793 at a dose of 2.5 mg/m(2)/day over 5 min for 5 consecutive days every 3 weeks. Thirty-four patients were enrolled and 23 patients were eligible for the evaluation of efficacy. Eleven patients experienced grade 4 neutropenia. Other related grade 3/4 adverse events included asthenia (three patients), stomatitis (1), myalgia (1) and increase of serum bilirubin (2). The main toxicity was hypertension occurring in seven out of 34 patients. There were no objective responses, 7 patients had stable disease. These results do not support the further evaluation of LU 103793 in metastatic breast cancer patients using this dose and schedule.