Delineation of the interactions between the chemotherapeutic agent eribulin mesylate (E7389) and human CYP3A4

Effects of Eribulin on the RNA Content of Extracellular Vesicles Released by Metastatic Breast Cancer Cells

Extracellular vesicles (EVs) are small lipid particles secreted by almost all human cells into the extracellular space. They perform the essential function of cell-to-cell communication, and their role in promoting breast cancer progression has been well demonstrated. It is known that EVs released by triple-negative and highly aggressive MDA-MB-231 breast cancer cells treated with paclitaxel, a microtubule-targeting agent (MTA), promoted chemoresistance in EV-recipient cells. Here, we studied the RNA content of EVs produced by the same MDA-MB-231 breast cancer cells treated with another MTA, eribulin mesylate. In particular, we analyzed the expression of different RNA species, including mRNAs, lncRNAs, miRNAs, snoRNAs, piRNAs and tRNA fragments by RNA-seq. Then, we performed differential expression analysis, weighted gene co-expression network analysis (WGCNA), functional enrichment analysis, and miRNA-target identification. Our findings demonstrate the possible involvement of EVs from eribulin-treated cells in the spread of chemoresistance, prompting the design of strategies that selectively target tumor EVs.

Eribulin, Child-Pugh score, and liver-function tests: lessons from pivotal breast cancer studies 301 and 305

Background

The recommended starting dose of eribulin in patients with hepatic impairment is based on the Child-Pugh score, largely informed by a pharmacokinetic study of 18 patients. In the pivotal studies of eribulin in metastatic breast cancer (Study 301 and Study 305 [EMBRACE]), entry criteria and dose modifications were based on liver-function test (LFT) results rather than Child-Pugh score. In populations such as patients with metastatic breast cancer, in which metastatic infiltration is the predominant cause of hepatic impairment, using Child-Pugh score may be problematic; in clinical practice, it has been more common for oncologists to make dosing decisions based on LFTs. To address this, the effects of abnormal baseline LFT results on eribulin efficacy and safety were investigated.

Methods

In this pooled post hoc analysis, 1062 patients who were randomized to receive eribulin in Studies 301 and 305 were divided into 4 groups: (A) no elevated LFT results (no liver impairment); (B) increased levels of aspartate aminotransferase and/or alanine aminotransferase; (C) decreased albumin and/or increased levels of aspartate aminotransferase and/or alanine aminotransferase but not increased bilirubin; and (D) increased bilirubin. Patients were subcategorized by presence of liver metastasis. Drug exposure, dose intensity, and treatment-emergent adverse events (TEAEs) were analyzed.

Results

Eribulin mesylate mean dosage was 0.82 (group A)–0.65 mg/m²/week (group D). Group D had shorter treatment, more dose reductions/delays, more TEAEs leading to dose modifications, and numerically lower objective response rates and clinical benefit rates versus groups A–C. TEAE rates leading to dose modification were similar between group D (45.5%) and groups A–C (range, 43.5–54.9%) in the absence of liver metastases, but higher in group D (91.3%) compared with groups A–C (range, 41.7–54.3%) if liver metastases were present.

Conclusions

Mild elevations in bilirubin levels were associated with increased toxicity and a greater requirement for dose modifications. Based both on these study data and existing recommendations, we propose a novel scheme to guide initial dose selection in patients with metastatic breast cancer and hepatic impairment that is based on LFTs rather than Child-Pugh score.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-021-01407-w.

Eribulin in advanced breast cancer: safety, efficacy and new perspectives

Eribulin is a synthetic analog of halichondrin B belonging to microtubule-targeted agents with a distinct mechanism of inhibition of microtubule dynamics. This molecule has multiple nonmitotic effects on tumor biology, exhibiting effects on epithelial-mesenchimal transition and tumor vasculature. We review here preclinical and clinical studies on eribulin. The mitotic and nonmitotic effects together with its favorable safety profile make eribulin a unique drug with high potential in the treatment of metastatic breast cancer. The new emphasis of eribulin mechanism of action on vascular remodeling, microenvironment modifications and reversal of epithelial-mesenchimal transition paves the way to rethinking the use of the drug in an immunological perspective.

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.

Eribulin for the treatment of metastatic breast cancer: an update on its safety and efficacy

Breast cancer remains a leading cause of cancer-related death internationally. Treatment approaches for metastatic breast cancer have evolved in recent years; however chemotherapy remains a core component for the majority of patients. Agents such as anthracyclines and taxanes have been extensively studied and form standard treatment. Eribulin mesylate is a novel synthetic microtubule-directed chemotherapy, based on a naturally-occurring compound. Through phase I studies, eribulin was found to be tolerable and activity was seen in patients with metastatic breast cancer. Phase II studies in metastatic breast cancer further demonstrated its efficacy, with responses and survival which compare favorably with other studied chemotherapy agents. The phase III EMBRACE study showed superior survival for patients treated with eribulin compared with those who received a physician's choice control. This led to its approval for use in many countries in this setting. Its toxicity profile is well established and manageable for the most part, with the commonest reported toxicities being alopecia, fatigue, neutropenia and peripheral neuropathy. A second reported phase III study comparing eribulin to capecitabine failed to show an improvement in survival in pretreated patients. This article reviews the clinical pharmacology and mechanism of action of eribulin, and summarizes the results of the major preclinical and clinical studies of eribulin in metastatic breast cancer.

Clinical impact of eribulin in the treatment of breast cancer

SUMMARY 

Metastatic breast cancer is considered incurable, with a 5-year survival of approximately 23%. However, sequential chemotherapy regimens produce clinical benefit for patients, including prolonged progression-free and overall survival times. Eribulin is a convenient (<5 min infusion) and novel treatment that has shown activity and efficacy and tolerability in advanced breast cancer patients in Phase II and Phase III trials. Eribulin has also shown encouraging results as first-line treatment, either alone in patients with HER2- disease or in combination with trastuzumab in patients with HER2+ disease, in Phase II 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.

Pharmacokinetics of eribulin mesylate in patients with solid tumours receiving repeated oral rifampicin

AIM

Eribulin mesylate is a non-taxane microtubule dynamics inhibitor that was recently approved for treatment of metastatic breast cancer. The aim of this study was to determine the effect of rifampicin, a CYP3A4 inducer, on the plasma pharmacokinetics of eribulin in patients with solid tumours.

METHODS

An open-label, non-randomized phase I study was carried out. Patients received intravenous 1.4 mg m(-2) eribulin mesylate on days 1 and 15 and oral rifampicin 600 mg on days 9 to 20 of a 28 day cycle. Pharmacokinetic sampling for determination of eribulin plasma concentrations was performed up to 144 h following administration. AUC(0,∞) and C(max) for eribulin exposure without or with co-administration of rifampicin were subjected to an analysis of variance (anova) and corresponding 90% confidence intervals (CI) were calculated. Subsequently, patients were allowed to continue eribulin mesylate treatment with 1.4 mg m(-2) eribulin mesylate on days 1 and 8 of a 21 day cycle. Also the adverse event profile and anti-tumour activity were assessed.

RESULTS

Fourteen patients were included and 11 patients were evaluable for pharmacokinetic analysis. Co-administration of rifampicin had no effect on single dose exposure to eribulin (geometric least square means ratio: AUC(0,∞) = 1.10, 90% CI 0.91, 1.34 and C(max) = 0.97, 90% 0.81, 1.17). The most common treatment-related grade ≥3 adverse events were grade 3 neutropenia (4/14, 29%), leucopenia and fatigue (both 3/14, 21%).

CONCLUSIONS

These results indicate that eribulin mesylate may be safely co-administered with compounds that are CYP3A4 inducers.

Eribulin mesylate in patients with refractory cancers: a Phase I study

Eribulin mesylate (Halaven™, E7389) is a synthetic analog of the marine natural product halichondrin B that acts via a mechanism distinct from conventional tubulin-targeted agents. This Phase I study (clinicaltrials.gov identifier: NCT00326950) was the first to investigate eribulin mesylate in Japanese patients. The study determined the recommended dose, MTD, DLTs, safety, pharmacokinetics, and antitumor activity of eribulin administered on Days 1 and 8 of a 21-day cycle in Japanese patients with advanced solid tumors. Fifteen patients received eribulin mesylate 0.7-2.0 mg/m(2) as a 2- to 10-min intravenous injection. Neutropenia was the principal DLT. DLTs were observed in two of six patients treated at 1.4 mg/m(2), and in all three patients at 2.0 mg/m(2). The recommended dose was 1.4 mg/m(2) and the MTD was 2.0 mg/m(2). Neutropenia (67%), lymphocytopenia (20%), febrile neutropenia (33%), and fatigue (13%) were the most common grade 3 or 4 toxicities. Eribulin exhibited triphasic pharmacokinetics with a long terminal half-life, high volume of distribution, and low urinary clearance. Three patients achieved partial responses (two with NSCLC, one with head and neck cancer) at 1.4 mg/m(2) dose level. Eribulin mesylate, administered on Days 1 and 8 of a 21-day cycle, exhibits manageable tolerability at 1.4 mg/m(2). DLT was neutropenia.

Eribulin mesylate: a novel halichondrin B analogue for the treatment of metastatic breast cancer

PURPOSE

The pharmacology, pharmacokinetics, clinical efficacy, safety, and administration of eribulin in patients with metastatic breast cancer are reviewed.

SUMMARY

Classical chemotherapeutic agents for breast cancer have dominated treatment regimens even in the era of targeted therapy. Disease progression through these agents is often due to the development of resistance or lack of efficacy with these agents. Recently, a new nontaxane agent, eribulin mesylate, was approved for the treatment of metastatic breast cancer in patients who have received at least two prior chemotherapeutic agents. Eribulin is a member of a new class of synthetic cytotoxic agents derived from the Japanese sea sponge Halichondria okadai. Eribulin differs from other antimicrotubule agents in that it can bind to the microtubule cap and inhibit tubulin polymerization, leading to microtubule arrest. In Phase II clinical trials, eribulin demonstrated activity in extensively pretreated patients who had previously received an anthracycline, taxane, and capecitabine and had shown disease progression within the last six months of treatment. In a pivotal Phase III clinical trial of heavily pre-treated patients, patients who received eribulin versus the physician's treatment of choice showed a significant increase in overall and progression-free survival. Eribulin has a manageable adverse-effect profile, consisting mainly of neutropenia and fatigue. Eribulin has been associated with a low incidence of peripheral neuropathy.

CONCLUSION

Eribulin, a novel synthetic antimicrotubule agent that binds to the vinca domain of tubulin and inhibits the polymerization of tubulin, offers a new treatment option for metastatic breast cancer or locally advanced breast cancer.

Eribulin: A Novel Cytotoxic Chemotherapy Agent

OBJECTIVE:

To review the chemistry, pharmacology, pharmacokinetics, safety, and efficacy of eribulin (Halaven).

DATA SOURCES:

A literature search (up to December 2011) using the terms eribulin, Halaven, ER-086526, and E7389 was performed with PubMed, Google Scholar, selected Ovid bibliography searches, and the abstract search tool from the American Society of Clinical Oncology Annual Meetings and the San Antonio Breast Cancer Symposia. Additional references from the bibliographies of these articles were also assessed.

DATA EXTRACTION:

English-language preclinical and clinical studies on the chemistry, pharmacology, pharmacokinetics, safety, and efficacy of eribulin were reviewed.

DATA SYNTHESIS:

Eribulin is a novel microtubule inhibitor with a unique mechanism of action, which involves interaction with a distinct binding site on β-tubulin leading to G2/M phase cell-cycle arrest and apoptosis. Eribulin has been approved by the Food and Drug Administration for the treatment of metastatic breast cancer in patients who have been previously treated with an anthracycline and a taxane. In a pivotal Phase 3 study conducted in patients with metastatic breast cancer, eribulin 1.4 mg/m2, administered over 2-5 minutes as an intravenous infusion on days 1 and 8 of 21-day cycles, was associated with a significantly increased median overall survival of 13.1 months compared to the median overall survival of 10.6 months in the therapy of physician's choice. Eribulin has also shown activity in Phase 2 studies in other types of cancers, such as non–small cell lung cancer, prostate cancer, urothelial cancer, soft tissue sarcomas, and platinum-susceptible ovarian, fallopian tube, or peritoneal cancers. The most severe (grade 3/4) adverse effects associated with eribulin include neutropenia, leukopenia, and peripheral neuropathy. Common toxicities include fatigue, neutropenia, alopecia, anemia, and peripheral neuropathy.

CONCLUSIONS:

Eribulin is a promising new cytotoxic chemotherapy agent due to its ability to treat cancers that are refractory or resistant to other drugs as well as its manageable toxicity profile.

Eribulin -- a review of preclinical and clinical studies

Eribulin mesylate is a non-taxane, structurally simplified, completely synthetic, halichondrin B derivative with an end poisoning, microtubule inhibitory action. Preclinical studies have demonstrated activity in various cancer cell lines and synergistic action with gemcitabine, epirubicin, trastuzumab, cisplatin, docetaxel and vinorelbine. Eribulin has recently been approved by United States Food and Drug Administration as a third line therapy for metastatic breast cancer patients, who have previously been treated with an anthracycline and a taxane. It has also advanced to phase II trials in non-small cell lung cancer, pancreatic, prostate, bladder, head and neck cancers, sarcomas and ovarian and other gynecological tumors. Combination trials with carboplatin, gemcitabine, pemetrexed, cisplatin, and erlotinib are currently ongoing. Eribulin potentially has a low incidence of peripheral neuropathy. The predominant side effects are neutropenia and fatigue, which are manageable. This article reviews the available information on eribulin with respect to its clinical pharmacology, mechanism of action, pharmacokinetics, pharmacodynamics, metabolism, preclinical studies and clinical trials.

Eribulin mesylate in the treatment of metastatic breast cancer

The treatment of metastatic breast cancer (MBC) has become increasingly challenging as the primary goals of therapy include prolonging life without added toxicity. While multiple agents are approved for the therapy of MBC, there is no standard approach for therapy beyond the second-line. Eribulin mesylate, an analog of the marine sponge halichondrin B, is a non-taxane microtubule dynamics inhibitor with a mechanism of action distinct from other tubulin-targeted drugs. Based on a significant extension in overall survival seen in a Phase III clinical trial, eribulin was approved for third-line therapy in MBC patients following anthracycline and taxane failure. Eribulin has a manageable toxicity profile and a low incidence of peripheral neuropathy. In this review, we discuss the natural source of eribulin, pharmacology, mode of action, preclinical and clinical data, and patient-focused perspectives.

Eribulin

Eribulin (eribulin mesylate) is a non-taxane microtubule dynamics inhibitor with tubulin-based antimitotic activity and chemotherapeutic effects. Eribulin is used in the treatment of patients with locally advanced or metastatic breast cancer who have previously been treated with at least two chemotherapeutic regimens, including an anthracycline and a taxane. In in vitro studies, eribulin displayed antiproliferative activity against human breast cancer cell lines. Regression and elimination of breast tumours were observed in human tumour xenograft models. In the randomized, open-label, multinational, phase III EMBRACE trial in patients with locally recurrent or metastatic breast cancer, median overall survival was significantly longer in patients who received intravenous eribulin (n = 508) [13.1 months] compared with that in patients who received a treatment of physician's choice (n = 254) [10.6 months; hazard ratio 0.81; 95% CI 0.66, 0.99; p = 0.041]. Prior to enrolment, study participants had received between two and five chemotherapeutic regimens, including an anthracycline and a taxane. Consistent with the findings of earlier phase I and II trials, eribulin was reported to have a manageable tolerability profile in the EMBRACE trial. Peripheral neuropathy (incidence 5%) was the most common adverse event resulting in the discontinuation of eribulin treatment. The most common grade 3/4 adverse events in the eribulin group were neutropenia, leukopenia and asthenia or fatigue.

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.

Eribulin mesylate as a microtubule inhibitor for treatment of patients with metastatic breast cancer

Metastatic breast cancer (MBC) remains an incurable disease, with the goals of care aimed at maximizing the patient's duration and quality of life. Treatment options for MBC have become more efficacious and numerous. In addition to endocrine and chemotherapy agents, a number of targeted agents, including trastuzumab and bevacizumab, have further enhanced the landscape of therapeutic options. Eribulin mesylate (E7389) is a nontaxane microtubule dynamics inhibitor, and a structurally simplified synthetic analog of the natural marine product, halichondrin B, with a novel mechanism of action that has shown antitumor activity in pretreated MBC. Eribulin has shown a manageable tolerability profile in Phase I-II clinical trials and an improvement in overall survival compared with treatment of physician's choice, without relevant toxicities in a recently published Phase III trial. This review will focus on eribulin as a new active agent for MBC and its role in the management of breast disease.

Mass balance study of [¹⁴C]eribulin in patients with advanced solid tumors

This mass balance study investigated the metabolism and excretion of eribulin, a nontaxane microtubule dynamics inhibitor with a novel mechanism of action, in patients with advanced solid tumors. A single approximately 2 mg (approximately 80 μCi) dose of [¹⁴C]eribulin acetate was administered as a 2 to 5 min bolus injection to six patients on day 1. Blood, urine, and fecal samples were collected at specified time points on days 1 to 8 or until sample radioactivity was ≤1% of the administered dose. Mean plasma eribulin exposure (627 ng · h/ml) was comparable with that of total radioactivity (568 ng Eq · h/ml). Time-matched concentration ratios of eribulin to total radioactivity approached unity in blood and plasma, indicating that unchanged parent compound constituted almost all of the eribulin-derived radioactivity. Only minor metabolites were detected in plasma samples up to 60 min postdose, pooled across patients, each metabolite representing ≤0.6% of eribulin. Elimination half-lives for eribulin (45.6 h) and total radioactivity (42.3 h) were comparable. Eribulin-derived radioactivity excreted in feces was 81.5%, and that of unchanged eribulin was 61.9%. Renal clearance (0.301 l/h) was a minor component of total eribulin clearance (3.93 l/h). Eribulin-derived radioactivity excreted in urine (8.9%) was comparable with that of unchanged eribulin (8.1%), indicating minimal excretion of metabolite(s) in urine. Total recovery of the radioactive dose was 90.4% in urine and feces. Overall, no major metabolites of eribulin were detected in plasma. Eribulin is eliminated primarily unchanged in feces, whereas urine constitutes a minor route of elimination.

Eribulin (Halaven): a new, effective treatment for women with heavily pretreated metastatic breast cancer

Although metastatic breast cancer remains essentially incurable, many patients previously treated with an anthracycline, taxane, and capecitabine are relatively fit and keen to receive further therapy. Several drugs are used in this setting, but with little evidence of clinically relevant benefit, and none have previously shown improved survival. Eribulin (Halaven®) is a nontaxane tubulin-binding agent with a novel mode of action, and was recently approved by the European Medicines Agency and US Food and Drug Agency as a single agent for patients with heavily pretreated metastatic breast cancer. This review provides an overview of the discovery, and preclinical and clinical development of eribulin, culminating in the recently published EMBRACE metastatic breast cancer study.

Eribulin mesylate, a novel microtubule inhibitor in the treatment of breast cancer

BACKGROUND

Microtubule-targeted agents are one of the most common classes of chemotherapeutic drug for the treatment of breast cancer. Limitations of current microtubule-targeted agents such as primary or secondary resistance of cancer cells and side effects like neuropathy prompted the discovery and introduction of newer more effective drugs. This review aims to provide a summary of the novel halichondrin B analog eribulin mesylate (E7389) and illustrate where it is placed in the treatment arena versus other agents that are approved or are currently in various stages of clinical development.

METHODS

Preclinical and clinical trial (phases I-III) data for eribulin were obtained from scientific journals and meeting abstracts, posters, and oral presentations. The use of current and other emerging microtubule inhibiting agents in breast cancer was also surveyed and briefly reviewed.

RESULTS

Eribulin mesylate at a dose of 1.4 mg/m(2) given on days 1 and 8 of a 21-day cycle increased overall survival in patients with metastatic breast cancer (MBC). Neutropenia, fatigue, alopecia, nausea and anemia were common adverse events (AEs) associated with eribulin in clinical studies. A low incidence of peripheral neuropathy was also associated with eribulin in clinical studies (21-26%). Other emerging microtubule targeted agents, such as vinflunine and larotaxel, also reported efficacy in patients with MBC who had received prior chemotherapy, with grade 3/4 neutropenia being the most common AEs for both agents.

CONCLUSIONS

Eribulin mesylate offers clinical activity in advanced breast cancer through improved overall survival, its favorable side-effect profile and convenience of preparation and administration.

Eribulin mesylate: a promising new antineoplastic agent for locally advanced or metastatic breast cancer

More than one million women worldwide are diagnosed with breast cancer every year. For those diagnosed with metastatic breast cancer, the 5-year survival rates are low as, ultimately, patients develop tumors that become refractory to treatment. In clinical trials, eribulin mesylate (E7389) – a novel nontaxane microtubule dynamics inhibitor – demonstrated efficacy in patients with various solid tumors, in particular, those with heavily pretreated metastatic breast cancer. The Eisai Metastatic Breast Cancer Study Assessing Physician’s Choice Versus E7389 (EMBRACE) study observed a significant increase in overall survival with eribulin compared with treatment of physician’s choice (median: 13.1 vs 10.6 months, respectively). Based on these results, eribulin recently received approval by the US FDA for the treatment of patients with metastatic breast cancer who have received at least two prior chemotherapeutic regimens including an anthracyline and a taxane. In addition, eribulin has a manageable tolerability profile, requires no premedication and has shorter infusion times than most other microtubule-targeted agents.

Management of venous thromboembolism and the potential to impact overall survival in patients with cancer

The risk of venous thromboembolism (VTE) in patients with cancer is 6-12-fold higher than in the general population, and VTE is the second leading cause of death in this population, after cancer itself. The etiology underlying the increased risk of VTE is multifactorial and complex, involving patient-, tumor-, and treatment-related factors. In patients with cancer, cumulative results from studies in those with VTE versus without VTE suggest that anticoagulation therapy, particularly with low-molecular-weight heparins, prevents morbidity and may reduce mortality. Despite the availability of effective and safe therapeutic options, VTE is often underrecognized and suboptimally managed. Interventions such as assessing individual patient risk of VTE, providing VTE prophylaxis and/or prompt treatment, and adopting VTE guidelines are essential aspects of cancer-related care. Aggressive VTE management and strategies are critical to improving survival in patients with cancer and VTE.

Phase I study of eribulin mesylate administered once every 21 days in patients with advanced solid tumors

PURPOSE

To evaluate the maximum tolerated dose (MTD), dose-limiting toxicities (DLT), and pharmacokinetics of eribulin mesylate (E7389), a halichondrin B analogue, administered every 21 days in patients with advanced solid tumors.

EXPERIMENTAL DESIGN

Eribulin mesylate was given as a 1-hour infusion every 21 days at doses of 0.25, 0.5, 1, 2, 2.8, and 4 mg/m(2). The MTD was identified using an accelerated titration design. The pharmacokinetics of eribulin were evaluated in the plasma and urine with the first dose.

RESULTS

Twenty-one patients were enrolled. At 4 mg/m(2), three patients experienced a DLT of febrile neutropenia on day 7. The dose level was reduced to 2.8 mg/m(2) where two of three patients experienced dose-limiting febrile neutropenia. Six additional patients were enrolled at 2 mg/m(2) (seven patients in total received this dose) and one of these patients experienced a neutropenic DLT. The MTD of eribulin mesylate was therefore 2 mg/m(2). Nonhematologic toxicities included alopecia, fatigue, anorexia, and nausea. Pharmacokinetic analysis showed linear kinetics for eribulin over the dose range studied and a terminal half-life of 2 days. The plasma-concentration-time profile exhibited a rapid distribution phase followed by a slow elimination phase. Drug clearance was nonrenal. One patient with non-small cell lung cancer achieved an unconfirmed partial response and 12 patients had stable disease.

CONCLUSIONS

Eribulin mesylate administered as a 1-hour infusion every 21 days has a manageable toxicity profile at 2 mg/m(2), with further dose escalation limited by neutropenia.