Genta Incorporated announced results from its Phase 2 clinical trial using tesetaxel as initial, single-agent chemotherapy in women with advanced breast cancer. Tesetaxel is an oral taxane in clinical development. The trial is lead by Memorial Sloan-Kettering Cancer Center, New York, NY, in collaboration with three other US centers.
Women were eligible if they had not received chemotherapy for locally advanced or metastatic HER2-negative breast cancer. Prior adjuvant chemotherapy was allowed if the recurrence was at least 12 months from the last dose. Forty-six patients were accrued to the trial, and 44 are currently evaluable for response. 70% of patients had received adjuvant chemotherapy; more than 80% of those regimens had included an injectable taxane. More than 50% of patients had received local radiotherapy, and approximately two-thirds had progressed on one more hormonal therapies.
Major objective responses were observed in 20 of 44 patients (45%), including one complete response and nineteen partial responses. Seven of the major responders cleared more than 75% of their measurable disease. The disease-control/clinical-benefit rate, which includes major responders and patients with stable disease, was 82%.
Exploratory analyses showed that 17 of 35 patients (49%) whose disease was estrogen receptor positive (ER+) had major responses. Median progression-free survival in the ER+ population was 7.3 months. In women with "triple-negative" disease, which is relatively insensitive to chemotherapy, 3 of 9 patients responded 33%.
Tesetaxel was generally well-tolerated. Neutropenia was the most common Grade 3-4 adverse event. The incidence of Grade 4 neutropenia was sharply reduced (from 32% to 11%) after dose escalation (from the starting level of 27 mg/m2 to 35 mg/m2) was discontinued a change that has now been incorporated into all protocols. Consistent with prior studies, no hypersensitivity reactions were observed.
"These data confirm results from our prior study, both of which show substantial activity for tesetaxel in patients with advanced, HER2-negative breast cancer", said Dr. Loretta M. Itri, Genta's President, Pharmaceutical Development, and Chief Medical Officer.
"Genta is also exploring an alternate dosing schedule in this population using weekly treatment. Based on this favorable experience, and after conferring with regulatory authorities in the U.S. and EU, Genta plans to proceed with a new randomized trial of tesetaxel as initial, single-agent chemotherapy for patients with recurrent breast cancer."
Ref : http://www.genta.com/Products_and_Pipeline/Tesetaxel/Tesetaxel.html