Endocyte has presented data from a phase 2a clinical trial for EC145, currently in development as a potential treatment for advanced ovarian cancer. Results were presented at the European Society of Gynaecologic Oncology meeting in Belgrade, Serbia. Reportedly, in 49 women with advanced-stage ovarian cancer, EC145 was shown to have anti-tumor activity in a significant percentage of trial participants.
Participants had disease that was highly resistant to standard chemotherapy. Participants had a median of four prior exposures to chemotherapy (with a range of 1 to 14), and 88% were diagnosed with ‘bulky disease’ defined as having a tumor volume of greater than five centimeters in diameter. In spite of this, the overall disease control rate, defined as stable disease, partial or complete response to therapy, was 40.8% (20 of 49), claims the company.
The company said that prior to the start of treatment with EC145, participants were scanned with 99mTc-EC20, a molecular imaging agent that binds to folate receptors (FR) and is being developed by Endocyte as a companion diagnostic tool to identify patients whose tumors express FR, the molecular target for the EC145 therapy.
When scanned with EC20, 76% of patients were found to be folate-receptor ‘positive.’ In the subgroup of patients, who were EC20 ‘positive’ and who had failed four or fewer prior therapies, the disease control rate was 75% (9 of 12), and two patients exhibited a RECIST partial response.
Richard Messmann, vice president for medical affairs at Endocyte, said: “These preliminary results provide significant additional support for Endocyte’s technology platform and for the important role that Endocyte’s co-development of targeted therapeutics and companion diagnostics can play in cancer drug discovery. Based upon these promising results, EC145 is now being evaluated in our Phase 2b PRECEDENT study, an international randomized study of EC145 in combination with Doxil/Caelyx versus Doxil/Caelyx alone in women with platinum-resistant ovarian cancer.”