Eribulin mesylate for the treatment of late-stage breast cancer.

INTRODUCTION: Chemotherapy agents, particularly anthracycline and taxane, have demonstrated their significance in metastatic breast cancer. However, improving overall survival in late-stage breast cancer remains a challenge. Eribulin mesylate, a new chemotherapy agent, has a proven significance in this setting. Eribulin mesylate is a synthetic analog of a macrolide isolated from a marine sponge. It inhibits microtubule polymerization, inducing mitosis arrest and apoptosis, and aggregates soluble tubulin in nonproductive form. In Phase II studies, this drug has shown a partial and stable response. The Phase III EMBRACE study showed that eribulin mesylate improved overall survival, compared with the physician's choice of treatment, in women who had received two to five prior chemotherapy regimens, including anthracycline and taxane for advanced breast cancer (median overall survival: 13.1 versus 10.6 months HR 0.81, p = 0.041). This compound is well tolerated. The most common adverse event is neutropenia. AREAS COVERED: This paper provides an introduction to the drug, eribulin mesylate, along with an overview of the current drug market for late-stage breast cancer; it also reviews its pharmacodynamics, pharmacokinetics and clinical efficacy. EXPERT OPINION: Currently, eribulin mesylate is only the third single-agent chemotherapy that has improved overall survival (after anthracycline and taxane) in advanced breast cancer. These results, particularly in heavily pretreated breast cancer, suggest that this drug could become a new standard in the treatment of metastatic breast cancer, and should, therefore, be further developed in its earlier stages.