A phase II study of two topotecan regimens evaluated in recurrent platinum-sensitive ovarian, fallopian tube or primary peritoneal cancer: A Gynecologic Oncology Group Study (GOG 146Q)

Objective.To evaluate the efficacy and safety of topotecan in patients with recurrent ovarian, primary peritoneal, and fallopian tube carcinomas.Methods.A randomized phase II analysis of platinum-sensitive patients with measurable disease was performed independently assessing intravenous topotecan 1.25 mg/m2 daily × 5 every 21 days (regimen I) and topotecan 4.0 mg/m2/day on days 1, 8, and 15 of a 28-day cycle (regimen II). All patients were treated until disease progression, unmanageable toxicity, or patient refusal. Insufficient accrual related to regimen I resulted in a redesign of the study as a single arm phase II trial assessing only regimen II. More complete efficacy data is presented for regimen II as enrollment on regimen I was insufficient for some analyses.Results.A total of 81 patients were enrolled. One patient was ineligible. Fifteen patients received regimen I, while 65 patients were treated with regimen II. The response rate on regimen I (daily × 5) was 27% (90% CI: 10–51%) and 12% (90% CI: 6–21%) on regimen II (weekly). The median PFS and OS were 4.8 and 27.8 months, respectively, for regimen II. Grade 3/4 neutropenia rate was 93% with daily × 5 dosing and 28% for weekly treatment. Febrile neutropenia was very low in both groups.Conclusion.The weekly regimen of topotecan appeared less active but resulted in less toxicity than the daily regimen in platinum-sensitive recurrent ovarian cancer patients.

Research highlights
► Weekly topotecan on days 1, 8, and 15 every 28 days appeared to have limited activity.
► Weekly schedule resulted in less toxicity than a daily × 5 every 21 days schedule.
► Based on desired efficacy and toxicity, choice of schedule needs to be individualized.