Phase II study of a new vinca alkaloid derivative, S12363, in advanced breast cancer.
Raktažodžiai
Santrauka
Vinca alkaloids are widely used in the medical treatment of breast cancer. Our study aimed to evaluate the therapeutic activity of a new vinca alkaloid derivative, S12363 (vinfosiltine), which is 36 and 72 times more cytotoxic in vitro than vincristine and vinblastine, respectively. Because phase I studies did not allow a choice of the best treatment schedule, a randomization was performed between two schedules with the same dose intensity, that is, 0.3 mg/m2 given weekly or 0.6 mg/m2 given every 2 weeks. A total of 16 patients with advanced breast cancer who had failed a first-line treatment without any vinca alkaloid were entered in the study. Additionally, 6 women received the bimonthly regimen as first-line treatment of advanced breast cancer. Altogether, 17 patients received, prior to vinfosiltine, an anthracycline-based regimen given either as adjuvant (n = 4) or as first-line palliative treatment (n = 13). All 22 patients were evaluable for both toxicity and response. Neutropenia was the main toxic event (maximal toxicity per patient) with grade 3 (WHO) toxicity developing in 7/22 patients and grade 4, in 8/22. Other severe toxicities included leukopenia (n = 9), anemia (n = 1), diarrhea (n = 1), constipation (n = 1), and fatigue (n = 1). No patient achieved a complete or partial response. Vinfosiltine does not appear to have significant single-agent activity in advanced breast cancer at the doses and the schedules used in our study.