Efficacy and Safety Study of Sorafenib With Topotecan in Patients With Platinum-resistant Recurrent Ovarian Cancer

Ovarian cancer continues to be a leading cause of cancer-related deaths in women and is the leading cause of deaths attributed to gynecologic malignancies. Because ovarian cancer is usually asymptomatic in its early stages, the disease often has spread outside of the pelvic region at the time of diagnosis and requires debulking surgery followed by systemic chemotherapy. First-line chemotherapy involves platinum-based treatments, including the widely adopted regimens of cisplatin/paclitaxel, carboplatin/paclitaxel, and single-agent carboplatin. Although these regimens yield relatively satisfactory tumor response rates, the majority of patients experience disease recurrence and receive additional treatments. For such patients, a number of antitumor agents with novel mechanisms of action (topotecan, gemcitabine, pegylated liposomal doxorubicin, docetaxel, etoposide) have been applied, in addition to retreatment with platinum, with the goal of re-establishing remission or disease control, minimizing disease-related symptoms, improving quality of life, and extending patient survival. Of these agents, topotecan (Hycamtin®; GlaxoSmithKline) is one of the best-characterized agents in the recurrent setting. Topotecan is an S-phase 1-dependent cytotoxic agent that targets the topoisomerase I enzyme and exhibits broad activity in solid tumors and is approved for the treatment of recurrent ovarian cancer in US and in most western countries. Data from preclinical and clinical studies reported in the last 2 years demonstrate the importance of several proangiogenic factors in the tumorigenesis and prognosis of ovarian cancer, suggesting possible new targets for antiangiogenic therapy. Once-daily oral treatment with Sorafenib produces broad spectrum antitumor efficacy in preclinical tumor models including also xenograft models of ovarian carcinoma. Preliminary antitumor activity has been reported in single ovarian cancer patients in several phase I and phase II studies. Most promising strategy in the therapy of advanced and recurrent ovarian cancer seems to be the combination of cytotoxic agents and targeted therapies. Furthermore an oral therapy to achieve and maintain long term tumor control seems to be very attractive. Therefore Sorafenib and Topotecan would make a rational therapeutic strategy for combination in recurrent ovarian cancer.