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

Background: To evaluate the toxicity and efficacy of a newly developed topoisomerase I inhibitor, CKD-602 in second-line therapy of ovarian cancer.

Methods: We 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 > or =6 months) and 6 had platinum-resistant disease (minimum treatment free interval <6 months). CKD-602 (0.5 mg/m(2)/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.

Results: The 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.

Conclusions: The newly developed topoisomerase I inhibitor, CKD-602, showed activity against both platinum-sensitive and -resistant ovarian cancer, with acceptable toxicity.