High Response Rate to Topotecan/Cisplatin in Ovarian Cancer

NEW YORK—Prolonged topotecan (Hycamtin) infusion combined with cisplatin (Platinol) is an effective first-line therapy for ovarian cancer, with almost all patients in a recent study responding.

James Speyer, MD, professor of clinical medicine, New York University Medical Center, presented the results at the 36th Annual Meeting of the American Society of Clinical Oncology. The lead investigator was Howard Hochster, MD, associate professor of clinical medicine.

The subjects were 60 women (median age, 58) with previously untreated epithelial ovarian cancer of stage IC or greater.

The first four patients were treated with cisplatin at 75 mg/m² on day 1 and topotecan continuous infusion at 0.4 mg/m²/day for 21 days. However, all had myelosuppression, and the remaining 56 patients received topo-tecan at 0.3 mg/m²/day for 14 days. Therapy was repeated every 28 days, and the median number of cycles was five.

Response rate was high in the 46 (of 56) patients who were assessable. Three had no evidence of disease. Twenty-one had a complete response, and another 19 had a partial response. Two patients were stable, and one patient progressed.

“The overall response rate for these patients was 93%,” Dr. Speyer said. The mean follow-up time was 22 months, and the median time to progression was 20 months.

Of the 56 patients receiving the lowered dose of topotecan, 18 were unable to complete the study, 12 due to toxicity. “There was significant hematologic toxicity, particularly neutropenia,” Dr. Speyer said. “This resulted in a significant number of delays or dose reductions to the topotecan.”

The major toxicities suffered by the 56 patients were grade 3/4 neutropenia, grade 2/3 anemia, and grade 3/4 thrombocytopenia. Half required blood transfusions, and one-fourth required platelet transfusions. Nonhematologic toxicities (nausea, vomiting, fatigue, and anorexia) were not severe.

 “We do believe that the activity observed in this non–taxane-containing trial warrants further study,” Dr. Speyer concluded. He and his collaborators are currently studying cisplatin plus 14-day continuous exposure to oral topotecan for four cycles followed by paclitaxel plus carboplatin for four cycles as first-line therapy for ovarian cancer.