Eisai Co., Ltd. has reported preliminary results of its global phase III study (Study FAR 131, MORAb-003-004) of farletuzumab (MORAb-003), an investigational compound under development at its US subsidiary, Morphotek, Inc., in patients with platinum-sensitive epithelial ovarian cancer in first relapse.

The phase III study was a multi-centre, randomized, double-blind, placebo-controlled, parallel-group comparative study of 1,100 patients with platinum-sensitive epithelial ovarian cancer in first relapse. The patients received standard-of-care therapy (carboplatin and a taxane) in combination with doses of either 1.25 mg/kg of farletuzumab, 2.5 mg/kg of farletuzumab, or placebo.

Preliminary results showed that the trial did not meet the pre-specified statistical criteria for significant progression-free survival (PFS), the study’s primary endpoint. The post hoc exploratory analysis showed, however, a trend toward improved PFS in some patient subsets and further analysis is ongoing. The preliminary safety analysis indicated that the most commonly reported adverse events were those known to be associated with the study chemotherapy agents. Additionally, some immune-mediated events were observed with farletuzumab. After further analysis of these clinical results, the company will determine a new development strategy based on discussion with external experts and the relevant health authorities.

Eisai remains committed to understanding the potential clinical benefits of farletuzumab in order to further contribute to patients with cancer, including patients with recurrent ovarian cancer, and their families.

Farletuzumab is a humanized, IgG1 monoclonal antibody that binds to the folate receptor-alpha (FRA), a folate-binding protein that is expressed on ovarian and several other epithelial cancer cells. Monoclonal antibodies are a type of immunotherapy used to treat cancer that are manmade versions of immune system proteins and can be designed to attack a specific part of a cancer cell. Immunotherapy drugs offer a method of treatment separate from chemotherapy.

Approximately 90 per cent of ovarian cancer tumours are epithelial (carcinomas) and often not diagnosed until the advanced stages of the disease. Although clinical complete remissions are obtained in the majority of patients through a combination of cytoreductive surgery and chemotherapy, relapse remains common.

Eisai’s commitment to meaningful progress in oncology research, built on scientific expertise, is supported by a global capability to conduct discovery and preclinical research, and develop small molecules, biologics, chemotherapies and supportive care agents for cancer across multiple indications.