Researchers presented preliminary safety and efficacy data for E7389 in the treatment of advanced, refractory breast cancer.

E7389 is a synthetic analog of halichondrin B ( HB ), which is a natural product shown in preclinical studies to have highly potent anti-cancer activity in vitro and in vivo.
Halichondrin B was originally isolated from a type of marine sponge.

This study was designed to evaluate E7389 as a monotherapy in patients with refractory breast cancer.

The primary endpoint of this trial was response rate, measured using the RECIST ( Response Evaluation Criteria In Solid Tumors ) criteria – a group of standards used to measure responses to treatment in solid tumors.

Of the 65 evaluable patients, 10 partial responses were confirmed at the 4th cycle assessment. Twenty-one patients had stable disease. In treatment-refractory patients with advanced breast cancer this preliminary response rate ( 15% ) appears promising.

Based on the preliminary results of this study, the predominant serious side effect related to E7389 was neutropenia.
Other side effects were considered mild to moderate and included nausea, fatigue, dehydration, arthralgias, dyspnea and neuropathy.
None of the patients discontinued the study due to hematological toxicity.

" The results from this study with E7389 appear promising, and clinical research on E7389 as a treatment for breast cancer is continuing," said Sandra Silberman, at Eisai Medical Research.

Seventy-one women were enrolled in the 28-day cycle patient group.
Preliminary efficacy data for 65 patients and safety data on 48 patients are available.
The 65 patients considered evaluable for response had completed at least their 2nd cycle of treatment and had a tumor assessment, which could be compared to their baseline.
This study is ongoing, and final results may change from the initial analysis.

Pre-clinical studies demonstrate that E7389 suppresses the growth of cellular microtubules, which are essential for cell division. By doing so, E7389 appears to stop the production of new cancer cells and ultimately results in the programmed death of the existing cancer cells, a process known as apoptosis.

Source: San Antonio Breast Cancer Symposium, 2005


XagenaMedicine2005