Eribulin in Cancer Treatment

Halichondrin B is a complex, natural, polyether macrolide derived from marine sponges. Eribulin is a structurally-simplified, synthetic, macrocyclic ketone analogue of Halichondrin B. Eribulin was approved by United States Food and Drug Administration in 2010 as a third-line therapy for metastatic breast cancer patients who have previously been treated with an anthracycline and a taxane. It has a unique microtubule dynamics inhibitory action. Phase III studies have either been completed or are currently ongoing in breast cancer, soft tissue sarcoma, and non-small cell lung cancer. Phase I and II studies in multiple cancers and various combinations are currently ongoing. This article reviews the available information on eribulin with respect to its clinical pharmacology, pharmacokinetics, pharmacodynamics, mechanism of action, metabolism, preclinical studies, and with special focus on clinical trials.

Can eribulin change the treatment algorithm in the management of breast cancer?

SUMMARY The US FDA approved eribulin as a third-line treatment for patients with metastatic breast cancer on 15 November 2010, based on the EMBRACE study. Eribulin has modified the management and enriched therapeutic options for patients with metastatic breast cancer. It has also improved life expectancy without increasing toxicity in this group of patients. In the future, this agent may achieve additional indications for treating malignancies other than breast cancer. This article summarizes data from various eribulin studies.

Survival benefit of eribulin mesylate in heavily pretreated metastatic breast cancer: what next?

Eribulin is a synthetic analog of halichondrin B, a non-taxane microtubule inhibitor extracted from the marine sponge, Halichondria okaida. It presents a novel mechanism of action and is active on cancer cells resistant to other antimicrotubule agents. It was granted approval in the USA and Europe for the treatment of heavily pretreated metastatic breast cancer. Early trials had shown activity in this setting with main toxicities being neutropenia and neuropathy in patients where quality of life is essential. Approvals were granted after a phase 3 trial demonstrated overall survival benefit in metastatic breast cancer previously treated with anthracyclines, taxanes, and capecitabine, in a setting where most treatments are failing to demonstrate a survival benefit. Recent data suggest that this survival benefit is also consistent in the elderly with no excess toxicity. Future strategies of eribulin are being tested in ongoing trials, evaluating this drug in earlier metastatic lines as well as in the adjuvant and the neoadjuvant settings.

Eribulin mesylate for the treatment of breast cancer

IMPORTANCE OF THE FIELD

Breast cancer is the most common cause of cancer-related death among women in the USA, and additional effective and well-tolerated chemotherapeutic agents are urgently needed. Eribulin mesylate (E7389), a synthetic analog of the marine macrolide halichondrin B, is a microtubule inhibitor with a unique tubulin binding site and mechanism of action.

AREAS COVERED IN THIS REVIEW

Based on a review of the literature between 2005 and 2010, we present a summary of eribulin and its clinical activity, specifically in metastatic breast cancer.

WHAT THE READER WILL GAIN

The mechanism of action of eribulin, preclinical data indicating antitumor activity of eribulin and data from Phase I and II clinical trials evaluating the efficacy and tolerability of eribulin are presented.

TAKE HOME MESSAGE

Based on data from Phase I and II clinical trials, we conclude that eribulin seems to have efficacy in metastatic breast cancer, even among women with heavily pretreated and taxane-resistant disease. In addition, eribulin has a manageable side-effect profile, consisting mainly of neutropenia and fatigue, and most notably a low incidence of peripheral neuropathy. With these encouraging results, additional Phase II and III studies are ongoing. Eribulin seems to be a promising new agent for the treatment of metastatic breast cancer.