5139 Background: Topotecan (Hycamtin), a topoisomerase-I-inhibitor is established in the therapy of relapsed OC. Ganem et al (ASCO 1998, abstr.1371) reported good tolerability and a remission rate of 22% for a topotecan/etoposide (T/E) combination in 80 heavily pretreated patients (pts). Gemcitabine has also demonstrated activity in resistant OC. In our recent published study (Ann Onc 2003) we describe a highly active combination of topotecan/gemcitabine (T/G) with a median TTP of 9.8 months for relapsed OC pts. Based on promising phase II results, a phase III study has been conducted to compare topotecan monotherapy (T) with T/E and T/G. The primary endpoint is median survival. Safety results from the planned interim analysis are reported for the first time. Methods: Pts with relapsed ovarian cancer after primary therapy have been stratified according to treatment-free interval of less or more than 12 months respectively. Arm A consisted of T 1.25mg/m2/d, d1–5; arm B of T 1.0mg/m2/d, d1–5 and E 50mg/d or...