Objective: Second-line treatment with paclitaxel and carboplatin enhances survival of women with platinum-sensitive recurrent ovarian cancer (ROC). However, because of its cumulative neurotoxicity, there is a strong demand for platinum-combinations with better therapeutic index. Because of its pharmacological properties, topotecan is a good adjunct to carboplatin in this setting, but its safety and efficacy remains to be defined.
Methods: Patients with platinum-sensitive ROC were eligible in this multicenter phase I/II study, stratified according to treatment-free interval (TFI). Dose level 0 consisted of topotecan 1 mg/m(2)/d1-3/q21d plus carboplatin AUC5/d3/q21d. DLT was defined as grade > or =3 neutropenia or thrombocytopenia or grade > or =3 non-hematological toxicity excluding alopecia, nausea and vomiting, accompanied by a treatment delay >1 week.
Results: From June 2004 to August 2005, 26 patients were enrolled, receiving a total of 145 cycles of chemotherapy. MTD was reached at topotecan 0.75 mg/m(2) and carboplatin AUC5. We observed a single grade 4 leucopenia. There were 3 (12%), 15 (58%) and 8 (31%) events of grade 3/4 hematological anaemia, leucopenia, and thrombocytopenia. Response rate was 67% (95% CI 43-85), median progression-free survival 9.5 months (95% CI 7.3-12.0), median overall survival 19.4 months (95% CI 12.3-26.9). None of the toxicity or efficacy endpoints were associated with TFI.
Conclusion: Topotecan and carboplatin is a well tolerated novel doublet option for women with platinum sensitive ROC. We encourage further studies on this approach, but to limit the doses of topotecan to 0.75 mg/m(2)/d1-3 and carboplatin AUC 5/d3.