Role of Farletuzumab in Epithelial Ovarian Carcinoma

Epithelial ovarian cancer (EOC) is the most lethal of the gynecologic malignancies, largely due to the advanced stage at diagnosis in most patients. Standard treatment for EOC is surgical debulking followed by platinum-based chemotherapy. While the majority of ovarian cancer patients will respond to initial chemotherapy, most will ultimately relapse. The major focus of current clinical trials for treatment of recurrent ovarian cancer is the use of targeted biologic agents. Folate receptor alpha (FR alpha) is upregulated in majority of EOC and correlated with tumor stage and grade. It is hypothesized that the presence of overexpressed FR alpha correlates with the propagation rate of the tumors. FR alpha is largely absent from normal tissue, making it an attractive therapeutic target. Farletuzumab (MORAb-003), a humanized monoclonal antibody against FR alpha, has shown antitumor activity in preclinical xenograft models. A Phase 1 dose escalation study did not demonstrate dose-limiting toxicities, or severe adverse effects. A phase 2 efficacy and safety study of farletuzumab with carboplatin and taxane in patients with platinum-sensitive EOC in first relapse, have shown an improved response rate and time to progression compared with historical controls. Recently, preliminary safety data from a phase 1 trial reported that the combination of farletuzumab, carboplatin and PLD has an acceptable safety profile in patients with platinum-sensitive EOC following first or second relapse. Two randomized, double-blind, placebo-controlled Phase 3 studies with farletuzumab plus chemotherapy have been done. A trial of: farletuzumab with weekly paclitaxel in platinum-resistant EOC closed in December 2011 with full report pending. A second trial of farletuzumab with carboplatin and taxane in platinum-sensitive EOC in first relapse is slated to complete accrual in early 2012. Results from these trials will help define the role of farletuzumab in EOC.