Phase II evaluation of CKD-602, a camptothecin analog, administered on a 5-day schedule to patients with platinum-sensitive or -resistant ovarian cancer

BackgroundTo evaluate the toxicity and efficacy of a newly developed topoisomerase I inhibitor, CKD-602 in second-line therapy of ovarian cancer.MethodsWe enrolled 24 patients with recurrent ovarian cancer, of median age 54 years (range, 39–64). Eleven patients had measurable lesions on CT scan, and the other 13 had increased serum CA-125 levels. Eighteen patients had platinum-sensitive disease (minimum treatment free interval ≥ 6 months) and 6 had platinum-resistant disease (minimum treatment free interval < 6 months). CKD-602 (0.5 mg/m2/day) was administered intravenously for 5 days every 3 weeks. The median number of courses per patient was 6 (range, 1 to 12). Response was evaluated by the evaluation of the size of the mass by CT scan and CA-125 response.ResultsThe overall response rate was 45.0% (9/20), with 4 patients exhibiting partial responses and 5 patients exhibiting 75% CA-125 responses in 20 evaluable patients. Of the 9 responsive patients, 8 were platinum-sensitive (8/15, 53.3%) and 1 was platinum-resistant (1/5, 20.0%). An additional 5 patients showed stable disease, whereas 6 patients exhibited progressive lesions. Of 24 patients, the most common toxicity was hematological, with grades 3 or 4 neutropenia developing in all 24 patients (100%) and in 94 cycles (71.7%). Grade 3 thrombocytopenia developed in 4 patients (16.7%) and 6 cycles (4.6%). None of the patients experienced grades 3 and 4 gastrointestinal toxicities, including nausea, vomiting, and anorexia.ConclusionsThe newly developed topoisomerase I inhibitor, CKD-602, showed activity against both platinum-sensitive and -resistant ovarian cancer, with acceptable toxicity.