Phase III trials of eribulin mesylate (E7389) in extensively pretreated patients with locally recurrent or metastatic breast cancer

Real world analysis of the efficacy and safety of eribulin compared to utidelone in combination with capecitabine for the treatment of metastatic breast cancer

BACKGROUND

The objective of this study was to compare the efficacy and safety of subsequent chemotherapy with single eribulin or utidelone combined with a capecitabine regimen in patients with advanced breast cancer who had previously been treated with anthracyclines and paclitaxel.

METHODS

This work was a retrospective analysis of 85 patients from July 2018 to July 2023. Forty-two and 43 patients were treated with the eribulin regimen and the utidelone/capecitabine regimen, respectively. The endpoints included progression-free survival, overall survival, the objective remission rate and safety. Survival analyses and multifactorial analyses were performed via the Kaplan‒Meier method, log-rank test and Cox regression models.

RESULTS

As of 15 April 2024, the mPFS durations of the patients in the utidelone/capecitabine and eribulin treatment groups were 7.7 and 5.2 months, respectively, and the mOS durations were 22.0 and 18.2 months, respectively. Subgroup analyses revealed that in advanced first-line therapy, the mPFS durations of the utidelone/capecitabine group and the eribulin group were 11.8 and 7.0 months, respectively, and this difference was significant. In the eribulin treatment arm, the mPFS of first-line therapy was 7.0, whereas it was 3.3 months for posterior-line therapy, and this difference was significant. The most common adverse reactions were neurotoxicity, hand‒foot syndrome, hematological toxicity, gastrointestinal toxicity, and abnormalities in hepatic and renal functions.

CONCLUSIONS

In conclusion, either utidelone/capecitabine or eribulin chemotherapy may result in a survival benefit with a tolerable adverse effect profile and favorable safety profile in patients with metastatic breast cancer. The first-line use of eribulin resulted in better PFS and ORR than posterior-line use, and the combination of utidelone/capecitabine represents a more efficacious approach in the advanced first-line therapy of breast cancer.

Hypoxia: syndicating triple negative breast cancer against various therapeutic regimens

Triple-negative breast cancer (TNBC) is one of the deadliest subtypes of breast cancer (BC) for its high aggressiveness, heterogeneity, and hypoxic nature. Based on biological and clinical observations the TNBC related mortality is very high worldwide. Emerging studies have clearly demonstrated that hypoxia regulates the critical metabolic, developmental, and survival pathways in TNBC, which include glycolysis and angiogenesis. Alterations to these pathways accelerate the cancer stem cells (CSCs) enrichment and immune escape, which further lead to tumor invasion, migration, and metastasis. Beside this, hypoxia also manipulates the epigenetic plasticity and DNA damage response (DDR) to syndicate TNBC survival and its progression. Hypoxia fundamentally creates the low oxygen condition responsible for the alteration in Hypoxia-Inducible Factor-1alpha (HIF-1α) signaling within the tumor microenvironment, allowing tumors to survive and making them resistant to various therapies. Therefore, there is an urgent need for society to establish target-based therapies that overcome the resistance and limitations of the current treatment plan for TNBC. In this review article, we have thoroughly discussed the plausible significance of HIF-1α as a target in various therapeutic regimens such as chemotherapy, radiotherapy, immunotherapy, anti-angiogenic therapy, adjuvant therapy photodynamic therapy, adoptive cell therapy, combination therapies, antibody drug conjugates and cancer vaccines. Further, we also reviewed here the intrinsic mechanism and existing issues in targeting HIF-1α while improvising the current therapeutic strategies. This review highlights and discusses the future perspectives and the major alternatives to overcome TNBC resistance by targeting hypoxia-induced signaling.

Marine Demospongiae: A Challenging Treasure of Bioactive Compounds

In the last decades, it has been demonstrated that marine organisms are a substantial source of bioactive compounds with possible biotechnological applications. Marine sponges, in particular those belonging to the class of Demospongiae, have been considered among the most interesting invertebrates for their biotechnological potential. In this review, particular attention is devoted to natural compounds/extracts isolated from Demospongiae and their associated microorganisms with important biological activities for pharmacological applications such as antiviral, anticancer, antifouling, antimicrobial, antiplasmodial, antifungal and antioxidant. The data here presented show that this class of sponges is an exciting source of compounds, which are worth developing into new drugs, such as avarol, a hydroquinone isolated from the marine sponge Disidea avara, which is used as an antitumor, antimicrobial and antiviral drug.

A separate assay of released and liposomal encapsulated eribulin in dog plasma by liquid chromatography with tandem mass spectrometry for its application to a pharmacokinetic study

Eribulin has been used as a drug for the treatment of metastatic breast cancer and liposomal formulation of eribulin (E7389-LF) is under development to achieve a wider therapeutic index. It is important to separately determine released and encapsulated drugs in a systemic circulation for liposomal drugs. In this study, a separate assay method was developed for the determination of released and total (encapsulated+released) eribulin concentrations in dog plasma by liquid chromatography with tandem mass spectrometry. The released eribulin in dog plasma was separated by ultrafiltration of plasma samples. Obtained plasma ultrafiltrate and untreated plasma samples recognized as released and total eribulin, respectively, were subjected to protein precipitation for extraction of eribulin. Eribulin was quantifiable from 0.1 ng/mL. Accuracy and precision of eribulin in both matrices were within ±15% and 15%, respectively, indicating a robust assay. Released and total eribulin concentrations in plasma were determined after intravenous administration of E7389-LF to dogs, resulting in minimal released eribulin in plasma. In conclusion, a robust method for released and total eribulin levels in dog plasma was developed and was successfully applied to a pharmacokinetic study in dogs to characterize the pharmacokinetic profiles. This article is protected by copyright. All rights reserved.

A phase II study of efficacy, toxicity, and the potential impact of genomic alterations on response to eribulin mesylate in combination with trastuzumab and pertuzumab in women with human epidermal growth factor receptor 2 (HER2)+ metastatic breast cancer

PURPOSE

There are limited data on trastuzumab-pertuzumab (HP)-based treatments beyond the first-line, HER2+ metastatic breast cancer (MBC) setting. We conducted a phase II study of eribulin mesylate, which extends survival in MBC, with HP in patients with previously treated HER2+ MBC to evaluate efficacy, toxicity, and genomic alterations driving therapeutic response.

METHODS

After a run-in phase for eribulin dosing, two cohorts were enrolled (Cohort A-no prior pertuzumab; Cohort B-prior pertuzumab). All patients received eribulin 1.4 mg/m² on days 1, 8 with standard-dose HP on day 1 (21-day cycles). The primary endpoint was objective response rate (ORR). Genomic characterization via whole exome sequencing (WES) was completed on tumor DNA and matched germline DNA from 19 patients.

RESULTS

The six-patient run-in established a dose of eribulin 1.4 mg/m² with HP. Cohorts A and B enrolled 17 and 7 patients, respectively. Accrual stopped early due to an evolving treatment landscape and slow enrollment. The ORR was 26.3% (95% Confidence Interval [CI] 9.2-51.2%) in Cohort A and 0% in Cohort B (95% CI 0-41.0%). WES revealed more frequent alterations in TP53 (p < 0.05, q > 0.05) in patients without clinical benefit (disease control for < 24 weeks) which was not significant after multiple hypothesis correction.

CONCLUSION

Eribulin-HP had manageable toxicity and modest clinical activity in patients without prior pertuzumab exposure. This study provides a preliminary landscape of somatic alterations in this patient cohort. Our data add to the literature on how genomic alterations may predict for therapy response/resistance, as we work to individualize choices in a quickly evolving HER2+ MBC treatment landscape.

TRIAL REGISTRATION

www.clinicaltrials.gov , NCT01912963. Registered 24 July 2013.

Capecitabine for hormone receptor-positive versus hormone receptor-negative breast cancer

BACKGROUND

Retrospective analyses suggest that capecitabine may carry superior activity in hormone receptor-positive relative to hormone receptor-negative metastatic breast cancer. This review examined the veracity of that finding and explored whether this differential activity extends to early breast cancer.

OBJECTIVES

To assess effects of chemotherapy regimens containing capecitabine compared with regimens not containing capecitabine for women with hormone receptor-positive versus hormone receptor-negative breast cancer across the three major treatment scenarios: neoadjuvant, adjuvant, metastatic.

SEARCH METHODS

On 4 June 2019, we searched the Cochrane Breast Cancer Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5) in the Cochrane Library; MEDLINE; Embase; the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials looking at chemotherapy regimens containing capecitabine alone or in combination with other agents versus a control or similar regimen without capecitabine for treatment of breast cancer at any stage. The primary outcome measure for metastatic and adjuvant trials was overall survival (OS), and for neoadjuvant studies pathological complete response (pCR).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. Hazard ratios (HRs) were derived for time-to-event outcomes, and odds ratios (ORs) for dichotomous outcomes, and meta-analysis was performed using a fixed-effect model.

MAIN RESULTS

We included 26 studies with outcome data by hormone receptor: 12 metastatic studies (n = 4325), 6 neoadjuvant trials (n = 3152), and 8 adjuvant studies (n = 13,457). Capecitabine treatment was added in several different ways across studies. These could be classified as capecitabine alone compared to another treatment, capecitabine substituted for part of the control chemotherapy, and capecitabine added to control chemotherapy. In the metastatic setting, the effect of capecitabine was heterogenous between hormone receptor-positive and -negative tumours. For OS, no difference between capecitabine-containing and non-capecitabine-containing regimens was observed for all participants taken together (HR 1.01, 95% confidence interval (CI) 0.98 to 1.05; 12 studies, 4325 participants; high-certainty evidence), for those with hormone receptor-positive disease (HR 0.93, 95% CI 0.84 to 1.04; 7 studies, 1834 participants; high-certainty evidence), and for those with hormone receptor-negative disease (HR 1.00, 95% CI 0.88 to 1.13; 8 studies, 1577 participants; high-certainty evidence). For progression-free survival (PFS), a small improvement was seen for all people (HR 0.89, 95% CI 0.82 to 0.96; 12 studies, 4325 participants; moderate-certainty evidence). This was largely accounted for by a moderate improvement in PFS for inclusion of capecitabine in hormone receptor-positive cancers (HR 0.82, 95% CI 0.73 to 0.91; 7 studies, 1594 participants; moderate-certainty evidence) compared to no difference in PFS for hormone receptor-negative cancers (HR 0.96, 95% CI 0.83 to 1.10; 7 studies, 1122 participants; moderate-certainty evidence). Quality of life was assessed in five studies; in general there did not seem to be differences in global health scores between the two treatment groups at around two years' follow-up. Neoadjuvant studies were highly variable in design, having been undertaken to test various experimental regimens using pathological complete response (pCR) as a surrogate for disease-free survival (DFS) and OS. Across all patients, capecitabine-containing regimens resulted in little difference in pCR in comparison to non-capecitabine-containing regimens (odds ratio (OR) 1.12, 95% CI 0.94 to 1.33; 6 studies, 3152 participants; high-certainty evidence). By subtype, no difference in pCR was observed for either hormone receptor-positive (OR 1.22, 95% CI 0.76 to 1.95; 4 studies, 964 participants; moderate-certainty evidence) or hormone receptor-negative tumours (OR 1.28, 95% CI 0.61 to 2.66; 4 studies, 646 participants; moderate-certainty evidence). Four studies with 2460 people reported longer-term outcomes: these investigators detected no difference in either DFS (HR 1.02, 95% CI 0.86 to 1.21; high-certainty evidence) or OS (HR 0.97, 95% CI 0.77 to 1.23; high-certainty evidence). In the adjuvant setting, a modest improvement in OS was observed across all participants (HR 0.89, 95% CI 0.81 to 0.98; 8 studies, 13,547 participants; moderate-certainty evidence), and no difference in OS was seen in hormone receptor-positive cancers (HR 0.86, 95% CI 0.68 to 1.09; 3 studies, 3683 participants), whereas OS improved in hormone receptor-negative cancers (HR 0.72, 95% CI 0.59 to 0.89; 5 studies, 3432 participants). No difference in DFS or relapse-free survival (RFS) was observed across all participants (HR 0.93, 95% CI 0.86 to 1.01; 8 studies, 13,457 participants; moderate-certainty evidence). As was observed for OS, no difference in DFS/RFS was seen in hormone receptor-positive cancers (HR 1.03, 95% CI 0.91 to 1.17; 5 studies, 5604 participants; moderate-certainty evidence), and improvements in DFS/RFS with inclusion of capecitabine were observed for hormone receptor-negative cancers (HR 0.74, 95% CI 0.64 to 0.86; 7 studies, 3307 participants; moderate-certainty evidence). Adverse effects were reported across all three scenarios. When grade 3 or 4 febrile neutropenia was considered, no difference was seen for capecitabine compared to non-capecitabine regimens in neoadjuvant studies (OR 1.31, 95% CI 0.97 to 1.77; 4 studies, 2890 participants; moderate-certainty evidence), and a marked reduction was seen for capecitabine in adjuvant studies (OR 0.55, 95% CI 0.47 to 0.64; 5 studies, 8086 participants; moderate-certainty evidence). There was an increase in diarrhoea and hand-foot syndrome in neoadjuvant (diarrhoea: OR 1.95, 95% CI 1.32 to 2.89; 3 studies, 2686 participants; hand-foot syndrome: OR 6.77, 95% CI 4.89 to 9.38; 5 studies, 3021 participants; both moderate-certainty evidence) and adjuvant trials (diarrhoea: OR 2.46, 95% CI 2.01 to 3.01; hand-foot syndrome: OR 13.60, 95% CI 10.65 to 17.37; 8 studies, 11,207 participants; moderate-certainty evidence for both outcomes).

AUTHORS' CONCLUSIONS

In summary, a moderate PFS benefit by including capecitabine was seen only in hormone receptor-positive cancers in metastatic studies. No benefit of capecitabine for pCR was noted overall or in hormone receptor subgroups when included in neoadjuvant therapy. In contrast, the addition of capecitabine in the adjuvant setting led to improved outcomes for OS and DFS in hormone receptor-negative cancer. Future studies should stratify by hormone receptor and triple-negative breast cancer (TNBC) status to clarify the differential effects of capecitabine in these subgroups across all treatment scenarios, to optimally guide capecitabine inclusion.

Application of marine natural products in drug research

New diseases are emerging as the environment changes, so drug manufacturers are always on the lookout for new resources to develop effective and safe drugs. In recent years, many bioactive substances have been produced in the marine environment, which represents an alternative resource for new drugs used to combat major diseases such as cancer or inflammation. Many marine-derived medicinal substances are in preclinical or early stage of clinical development, and some marine drugs have been put on the market, such as ET743 (Yondelis®). This review presents the sources, activities, mechanisms of action and syntheses of bioactive substances based on marine natural products in clinical trials and on the market, which is helpful to understand the progress of drug research by application of marine natural products.

Intrinsic and Extrinsic Factors Affecting Microtubule Dynamics in Normal and Cancer Cells

Microtubules (MTs), highly dynamic structures composed of α- and β-tubulin heterodimers, are involved in cell movement and intracellular traffic and are essential for cell division. Within the cell, MTs are not uniform as they can be composed of different tubulin isotypes that are post-translationally modified and interact with different microtubule-associated proteins (MAPs). These diverse intrinsic factors influence the dynamics of MTs. Extrinsic factors such as microtubule-targeting agents (MTAs) can also affect MT dynamics. MTAs can be divided into two main categories: microtubule-stabilizing agents (MSAs) and microtubule-destabilizing agents (MDAs). Thus, the MT skeleton is an important target for anticancer therapy. This review discusses factors that determine the microtubule dynamics in normal and cancer cells and describes microtubule-MTA interactions, highlighting the importance of tubulin isoform diversity and post-translational modifications in MTA responses and the consequences of such a phenomenon, including drug resistance development.

Microtubule-targeting agents and their impact on cancer treatment

Microtubule-targeting agents (MTAs) constitute a diverse group of chemical compounds that bind to microtubules and affect their properties and function. Disruption of microtubules induces various cellular responses often leading to cell cycle arrest or cell death, the most common effect of MTAs. MTAs have found a plethora of practical applications in weed control, as fungicides and antiparasitics, and particularly in cancer treatment. Here we summarize the current knowledge of MTAs, the mechanisms of action and their role in cancer treatment. We further outline the potential use of MTAs in anti-metastatic therapy based on inhibition of cancer cell migration and invasiveness. The two main problems associated with cancer therapy by MTAs are high systemic toxicity and development of resistance. Toxic side effects of MTAs can be, at least partly, eliminated by conjugation of the drugs with various carriers. Moreover, some of the novel MTAs overcome the resistance mediated by both multidrug resistance transporters as well as overexpression of specific β-tubulin types. In anti-metastatic therapy, MTAs should be combined with other drugs to target all modes of cancer cell invasion.

The NAME trial: a direct comparison of classical oral Navelbine versus Metronomic Navelbine in metastatic breast cancer

Chemotherapy for metastatic breast cancer (MBC) is in general given in cycles of maximum tolerated doses to potentially maximize the therapeutic outcome. However, when compared with targeted therapies for MBC, conventional and dose intensified chemotherapy has caused only modest survival benefits during the recent decades, often compromising the quality of life considerably. Navelbine is an antineoplastic agent that has shown efficacy in the treatment of a variety of cancer types, including breast cancer. Early clinical trials involving both breast cancer and lung cancer patients suggest that metronomic dosing of Navelbine might be at least as effective as classical administration (once weekly, etc.). The NAME trial compares these two strategies of Navelbine administration in MBC patients.

From natural products to drugs

It is frequently assumed, particularly in the last 15 plus years, that “Natural Product Structures” are no longer a source of drugs in the twenty-first century. In fact, this is not at all true. Even today, in the search for novel agents against manifold diseases, natural product structures, some quite old and some quite recent, are behind the compounds that are either recently (last 5–10 years) approved or that are now in clinical trials against manifold diseases of man. This chapter will cover agents approved since 2010 to the end of 2017 by the US FDA and its equivalent in other countries, plus selected agents that have entered clinical trials against major diseases such as cancer and infections that have “in their chemical pedigree” a natural product structure, even if the final product may be totally synthetic in nature.

Crambescidin 800, Isolated from the Marine Sponge Monanchora viridis, Induces Cell Cycle Arrest and Apoptosis in Triple-Negative Breast Cancer Cells

Triple negative breast cancer (TNBC) is currently the only group of breast cancers without an effective targeted therapy. Marine sponges have historically been a source of compounds with anticancer activity. In this study, we screened extracts from twenty marine sponges collected off the coast of Western Australia for cytotoxic activity against TNBC cells. One very active extract derived from the sponge Monanchora viridis was selected for bioactivity-guided fractionation. Through multiple steps of purification, we isolated a potent cytotoxic compound, which was identified as crambescidin 800 (C800). We found that C800 exhibited cytotoxic potency in a panel of breast cancer cells, of which TNBC and luminal cancer cell models were the most sensitive. In addition, C800 induced cell cycle arrest at the G2/M phase, resulting in a decline in the expression of cyclin D1, CDK4, and CDK6 in TNBC cells. This effect was associated with the inhibition of phosphorylation of Akt, NF-κB, and MAPK pathways, resulting in apoptosis in TNBC cells.

Advances in the treatment of soft tissue sarcoma: focus on eribulin

Eribulin mesylate is a synthetic derivative of halichondrin B isolated from a marine sponge. Its mechanism of action is through microtubule inhibition, which is different from that of taxanes. Eribulin has been approved for the treatment of metastatic breast cancer and more recently for non-operable or metastatic liposarcoma in patients who have received prior anthracycline chemotherapy. The major side effects of eribulin are bone marrow suppression including neutropenia, leukopenia, anemia, and fatigue/weakness, which can be well managed. In this article, we reviewed evidence from the latest published data on eribulin and its use in the treatment of soft tissue sarcomas. We explored the drug’s mechanism of action, pharmacodynamics, pharmacokinetics, and metabolism. Lastly, we reviewed all preclinical studies as well as clinical trials that investigated eribulin.

Identification of predictive markers of the therapeutic effect of eribulin chemotherapy for locally advanced or metastatic breast cancer

Background

The recently developed reagent, eribulin mesylate (eribulin), is a microtubule dynamics inhibitor with a mechanism of action that differs from those of taxanes and vinca alkaloids. This drug is considered to be a promising chemotherapeutic agent for the treatment of locally advanced or metastatic breast cancer (MBC). In this study, we investigated if variables such as tumor expression of β-tubulin class III, glutathione S-transferase pi (GSTP) 1 or transducin-like enhancer of split (TLE) 3 might act as predictive factors on the therapeutic effect of eribulin chemotherapy.

Methods

The subjects included 52 patients with MBC who underwent chemotherapy with eribulin. The expression levels of Estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor (HER) 2, Ki67, β-tubulin class III, GSTP-1 and TLE-3 were evaluated using immunostaining employing needle biopsy specimens.

Results

Patients with TLE3-negative tumors displayed significantly poorer outcomes regarding progression-free survival than patients with TLE3-positive tumors when prognosis within the group of patients with triple-negative breast cancer (TNBC) lesions was analyzed (p = 0.011, log-rank). In contrast, no such difference in prognosis was found in a comparison of TLE-3 positive/negative patients in the group of all patients (p = 0.433, log-rank) or of patients with non-TNBC lesions (p = 0.659, log-rank). Based on a univariate analysis of 22 TNBC cases, a better progression-free survival correlated significantly with a positive TLE3 expression in the tumor (p = 0.025). A multivariate logistic regression analysis including 22 patients with TNBC also showed that a positive TLE3 expression significantly correlated with a better progression-free survival (p = 0.037).

Conclusions

Our findings suggest that TLE3 is a useful marker for predicting the therapeutic effect of eribulin chemotherapy for TNBC.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3598-5) contains supplementary material, which is available to authorized users.

Synergistic effect of eribulin and CDK inhibition for the treatment of triple negative breast cancer

Activation of CDK2 in triple negative breast cancer (TNBC) can contribute to non-canonical phosphorylation of a TGFβ signaling component, Smad3, promoting cell proliferation and migration. Inhibition of CDK2 was shown to decrease breast cancer oncogenesis. Eribulin chemotherapy was used effectively in the treatment of TNBC. To this end, we tested therapeutic efficacy of a novel CDK2/9 inhibitor, CYC065, eribulin, and the combination of CYC065 and eribulin in 3 different TNBC cell lines, and an in vivo xenograft model. Specifically, we characterized cell proliferation, apoptosis, migration, cell cycle associated protein expression, treatment-related transcription factor activity, and tumor growth in TNBC. Treatment with CYC065 and eribulin in combination had a superior effect on decreasing cell proliferation, inducing apoptosis, and inhibiting migration in TNBC cell lines in vitro. Combination therapy inhibited non-canonical Smad3 phosphorylation at the T179 site in the protein linker region, and resulted in increased p15 and decreased c-myc expression. In a transcription factor array, combination treatment significantly increased activity of AP1 and decreased activity of factors including NFκB, SP1, E2F, and SMAD3. In an in vivo xenograft model of TNBC, individual and combination treatments resulted in a decrease in both tumor volume and mitotic indices. Taken together, these studies highlight the potential of this novel drug combination, CYC065 and eribulin, to suppress the growth of TNBC cells in vitro and in vivo, warranting further clinical investigation.

Eribulin shows high concentration and long retention in xenograft tumor tissues

Purpose

Eribulin, a synthetic analog of the natural product halichondrin B, is a microtubule dynamics inhibitor. In this study, we report the pharmacokinetic profiles of eribulin in mice, rats, and dogs following intravenous administrations with optimized and validated bio-analytical methods.

Methods

Eribulin was administered at 0.5 and 2 mg/kg in mice, 0.5 and 1 mg/kg in rats, and 0.08 mg/kg in dogs. Tumor and brain penetration of eribulin was also evaluated in LOX human melanoma xenograft models. Concentrations in plasma, tumor, and brain were measured by the LC–MS/MS method.

Results

The profiles of eribulin were characterized by extensive distribution, moderate clearance, and slow elimination in the three species. The pharmacokinetics are linear in mice and rats. In xenograft mice, the penetration into the brain was low, as expected, since eribulin is a P-glycoprotein substrate. In contrast to disposition in brain, the exposure of eribulin was approximately 20–30 times higher in tumor than that in plasma and half-lives were 17.8–35.9 h after both single and multiple dose regimens.

Conclusions

Eribulin was distributed rapidly and eliminated slowly in mice, rats, and dogs. The exposure of eribulin was approximately 20–30 times higher in tumor than in plasma in xenograft mice. These results might be caused by eribulin’s mechanism of action including increased perfusion in tumor by vascular remodeling effect.

Antiproliferative and Proapoptotic Activities of Marine Sponge Hyrtios erectus Extract on Breast Carcinoma Cell Line (MCF-7)

Background:

Marine sponge is a rich natural resource of many pharmacologically important compounds.

Objective:

Marine sponge Hyrtios erectus, collected from North Bay, South Andaman Sea, India, was screened for potential antiproliferative and proapoptotic properties on a breast adenocarcinoma cell line (MCF-7).

Materials and Methods:

3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to test the antiproliferative and cytotoxicity effects of the sponge extract. Analysis of apoptosis and cell cycle stages were done by flow cytometry. The expression of several apoptotic-related proteins in MCF-7 cells treated by the extract was evaluated by Western blot analysis. Various analytical techniques including Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance were employed to determine the identity of the active compounds in the sponge extract.

Results:

N-Hexane extract of the sponge inhibited proliferation of the MCF-7 cell line in a dose- and time-dependent manner. Exposure of the sponge extract triggered apoptosis of the MCF-7 cells, induced DNA fragmentation, and arrested the cells in G₂/M phase. Treatment of the sponge extract induced downregulation of antiapoptotic Bcl-2 protein and upregulation of Bax, caspase-3, caspase-9, and fragmented poly(ADP ribose)polymerase proteins in MCF-7 cells. Five bioactive compounds have been identified in the extract.

Conclusion:

The antiproliferative and proapoptotic activities of the tested extract suggested the pharmacologic potential of the identified compounds. Further characterization of the identified compounds are in progress.

SUMMARY

The N-hexane extract of the marine sponge Hyrtios erectus, collected from North Bay, South Andaman Sea, India, showed potential antiproliferative and proapoptotic properties against a breast adenocarcinoma cell line (MCF-7).

The sponge extract retarded the growth of breast carcinoma cell line MCF-7 cells in a time- and dose-dependent manner.

The sponge extract induced apoptosis of breast cancer cell line MCF-7 and arrested cells in G₂/M phase.

The sponge extract induced downregulation of Bcl-2 protein in MCF-7 cell line and upregulation of Bax, caspase-3, and cleaved PARP. Five bioactive compounds have been identified in the extract.

Abbreviations used: GC-MS: Gas chromatography-mass spectrometry; FT-IR: Fourier transform infrared spectroscopy; NMR: Nuclear magnetic resonance; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.

Economic evaluation of eribulin as second-line treatment for metastatic breast cancer in South Korea

Background

Metastatic breast cancer (MBC) is associated with poor prognosis, particularly for those patients with human epidermal growth factor receptor (HER2)-negative tumor. Similar to the rest of the world, treatment options are limited in South Korea following first-line chemotherapy with anthracyclines and/or taxanes. This study examined the cost-effectiveness and cost-utility of eribulin in South Korean patients with HER2-negative MBC who have progressed after usage of at least one chemotherapeutic regimen for advanced disease (second-line therapy).

Methods

A partition survival model was developed from the perspective of the South Korean health care system. The economic impact of introducing eribulin as second-line therapy for HER2-negative MBC was compared to that of capecitabine and vinorelbine. The analysis estimated incremental cost per life-year (LY), that is, cost-effectiveness, and cost per quality-adjusted life-year (QALY), that is, cost-utility, of eribulin for management of HER2-negative MBC in South Korea. The model accounted for overall survival, progression-free survival, drug costs, grade 3/4 adverse events, and health care utilization. Deterministic and probabilistic sensitivity analyses were performed to identify uncertainty in the results of the economic evaluation.

Results

Second-line eribulin was associated with greater benefits in terms of LY and QALY, compared to capecitabine and vinorelbine. The incremental cost-effectiveness ratio was ₩10.5M (approximately USD 9,200) per LY, and the incremental cost-utility ratio was ₩17M (approximately USD 14,800) per QALY in the basecase analysis. The incremental cost-utility ratio ranged from ₩12M (USD 10,461) to ₩27M (USD 23,538) per QALY in the deterministic sensitivity analysis. In the probabilistic sensitivity analysis, >99% of the simulations were below ₩50M (USD 42,300), and the lower and upper 95% confidence intervals were ₩3M (USD 2,600) and ₩24M (USD 20,900) per QALY, respectively.

Conclusion

There currently exist a limited number of treatment choices for women with HER2-negative MBC. Eribulin is a cost-effective option for second-line therapy in South Korea and should be added to the current indications for reimbursement.

Long-term efficacy and safety of a third-line treatment with eribulin plus trastuzumab in a young breast cancer patient

Eribulin mesylate is approved for the treatment of metastatic breast cancer (MBC) patients after progression with anthracyclines and taxanes. Eribulin appears especially promising when combined with trastuzumab, according to the results of a recent Phase II trial in first-line setting. Here we report the case of a young, pretreated, HER2(-) MBC patient, who achieved a long-term clinical benefit with eribulin alone and in combination with trastuzumab after re-biopsy on liver metastases showed HER2 amplification. Although it is unique for its evolving clinical/biomolecular picture, this case adds anecdotal evidence to the efficacy and tolerability of this combination. However, Phase III trials are warranted to confirm its potential in first and subsequent lines of MBC treatment.

Phase II randomized clinical trial evaluating neoadjuvant chemotherapy regimens with weekly paclitaxel or eribulin followed by doxorubicin and cyclophosphamide in women with locally advanced HER2-negative breast cancer: NSABP Foundation Study FB-9

Locally advanced breast cancer (LABC) is a good setting in which to monitor response to neoadjuvant chemotherapy, to downsize the tumor (which facilitates breast-conserving surgery), and to test newer agents in untreated patients. Eribulin (E) has shown activity in patients who have undergone previous taxane, anthracycline, and capecitabine treatment. We aimed to evaluate the neoadjuvant use of E followed by doxorubicin and cyclophosphamide (AC) in patients with HER2-negative LABC, using as a control a randomized group of women who received weekly paclitaxel (WP). Fifty women with LABC were accrued January-August 2013. Patients were randomized (1:2) to receive either WP (N = 19) for 12 treatments or E (N = 31) every 3 weeks for 4 cycles followed by AC every 3 weeks for 4 cycles before surgery. 17/19 patients who took WP and 25/30 who took E completed all cycles. Patients were evaluated by clinical examination and breast MRI at baseline and after completion of E or WP. Surgical pCR in breast and lymph nodes was determined by a local pathologist following chemotherapy. Forty-nine patients received ≥1 dose of neoadjuvant chemotherapy and are included in this analysis. Forty-eight underwent surgery; one had disease that was inoperable (on E) and is included as no-pCR patient. 17/19 of these patients who took WP completed 12 doses; 28/30 on E completed 4 cycles. Six discontinued treatment on WP, E, or AC. Both treatments were well tolerated. pCR on WP = 5/19(26 %) and on E = 5/30(17 %). Both regimens were equally well tolerated with no unexpected toxicities. pCR did not suggest higher activity with E than with other standard regimens in these LABC patients.

Pegylated liposomal doxorubicin (Lipo-Dox®) combined with cyclophosphamide and 5-fluorouracil is effective and safe as salvage chemotherapy in taxane-treated metastatic breast cancer: an open-label, multi-center, non-comparative phase II study

Background

Anthracycline and taxane are classes of drugs that are frequently used in the adjuvant and palliative settings of metastatic breast cancer (MBC); however, treatment failure occurs in most cases. Limited data demonstrated favorable response in MBC after previous taxane-based treatment. The aim of this study was to evaluate the efficacy and safety of pegylated liposomal doxorubicin (Lipo-Dox®) used as part of a combination salvage therapy for patients with MBC whose tumors progressed during or after taxane-based treatment.

Methods

Patients with MBC who failed to respond to previous taxane-based treatments were recruited. Treatment with pegylated liposomal doxorubicin (40 mg/m²), cyclophosphamide (500 mg/m²), and 5-fluorouracil (500 mg/m²) was administered every 3 weeks. Tumor response to treatment was determined by using the Response Evaluation Criteria in Solid Tumor criteria version 1.0, and left ventricular ejection fraction was measured before and after treatment using echocardiography. Each patient was followed for 30 days after the last dose of study medication or until resolution/stabilization of any drug-related adverse event.

Results

Forty-five patients were recruited. As of December 2012, the median follow-up duration was 29.8 months, the overall response rate was 41.9 %, the median progression-free survival was 8.2 months, and the median overall survival was 36.6 months for all treated patients. Grade 3/4 neutropenia, leucopenia, and neutropenic fever were observed in 14 %, 9 %, and 1 % of the cycles, respectively. Other non-hematologic adverse effects were mild to moderate and were manageable. No decrease in left ventricular ejection function was noted.

Conclusion

This regimen of combined of pegylated liposomal doxorubicin, cyclophosphamide, and 5-fluorouracil exhibited a promising overall response rate, progression-free survival rate, and overall survival rate, with a safe cardiac toxicity profile and manageable adverse effects. This regimen could be considered as a treatment option for patients with MBC whose tumors progressed during or after taxane-based treatment.

Therapies for triple negative breast cancer

INTRODUCTION

Triple negative breast cancer (TNBC) is a heterogeneous disease associated with a high risk of recurrence, and therapeutic options are currently limited to cytotoxic therapy. Germ-line mutations may occur in up to 20% of unselected patients with TNBC, which may serve as a biomarker identifying which patients may have tumors that are particularly sensitive to platinums and/or inhibitors of poly(ADP-ribose)polymerase. A substantial proportion of patients with TNBCs not associated with germ-line BRCA mutations may have tumors that are ‘BRCA-like’, rendering those individuals potential candidates for similar strategies.

AREAS COVERED

The purpose of this review is to highlight the current standard and experimental treatment strategies.

EXPERT OPINION

Recent research that has illuminated the molecular heterogeneity of the disease rationalizes its diverse biological behavior and differential response to chemotherapy. Modern technology platforms provide molecular signatures that can be mined for therapeatic interventions. Target pathways that are commonly dysregulated in cancer cells control cellular processes such as apoptosis, proliferation, angiogenesis, DNA repair, cell cycle progression, immune modulation and invasion, and metastasis. Novel trial design and re-defined endpoints as surrogates to clinical outcome have been introduced to expedite the development of breakthrough therapies to treat high-risk early-stage breast cancer.

Phase III open-label randomized study of eribulin mesylate versus capecitabine in patients with locally advanced or metastatic breast cancer previously treated with an anthracycline and a taxane

Purpose

This phase III randomized trial (ClinicalTrials.gov identifier: NCT00337103) compared eribulin with capecitabine in patients with locally advanced or metastatic breast cancer (MBC).

Patients and Methods

Women with MBC who had received prior anthracycline- and taxane-based therapy were randomly assigned to receive eribulin or capecitabine as their first-, second-, or third-line chemotherapy for advanced/metastatic disease. Stratification factors were human epidermal growth factor receptor-2 (HER2) status and geographic region. Coprimary end points were overall survival (OS) and progression-free survival (PFS).

Results

Median OS times for eribulin (n = 554) and capecitabine (n = 548) were 15.9 and 14.5 months, respectively (hazard ratio [HR], 0.88; 95% CI, 0.77 to 1.00; P = .056). Median PFS times for eribulin and capecitabine were 4.1 and 4.2 months, respectively (HR, 1.08; 95% CI, 0.93 to 1.25; P = .30). Objective response rates were 11.0% for eribulin and 11.5% for capecitabine. Global health status and overall quality-of-life scores over time were similar in the treatment arms. Both treatments had manageable safety profiles consistent with their known adverse effects; most adverse events were grade 1 or 2.

Conclusion

In this phase III study, eribulin was not shown to be superior to capecitabine with regard to OS or PFS.

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.

Eribulin in the Management of Advanced Breast Cancer: Implications of Current Research Findings

The search for cytotoxic agents from marine natural products ultimately led to the production of eribulin, which is a synthetic macrocyclic ketone analog of halichondrin B. Eribulin binds to tubulin to induce mitotic arrest and gained approval in Japan in May 2010; it was approved by the US Food and Drug Administration in November 2010 and the European Medicines Agency in March 2011 and was reimbursed by the Taiwan National Health Insurance in December 2014 for patients with metastatic breast cancer who had received at least one anthracycline and one taxane. The recommended regimen for eribulin mesylate comprises intravenous administration of 1.4 mg/m(2) (equivalent to 1.23 mg/m(2) eribulin) over two to five minutes on days 1 and 8 of a three-week cycle. Since 2011, various clinical investigations of eribulin monotherapy with dose or schedule modifications, combined use with other antineoplastic therapeutics, or head-to-head comparisons with specific agents have been performed in the management of advanced breast cancer. Ethnic-specific data from Japan and Korea indicate higher rates (>85%) of grade 3 or 4 neutropenia. Some anecdotal evidence suggests that eribulin can shrink brain and retinal metastases, which warrants further detailed studies. In this review, current observations of the effects of eribulin monotherapy are summarized and eribulin-backbone combination (bio-) chemotherapy is investigated.

Eribulin: a new-generation antimicrotubule agent in lung cancer therapy

ABSTRACT 

Microtubule antagonists are highly active agents for treatment of metastatic lung cancer, but can lead to significant toxicities and tumor resistance. Eribulin mesylate is a novel antimicrotubule agent that binds at a different site of the microtubule chain, and has been shown to be effective against many tumor types in several Phase II trials. Studies revealed many potential mechanisms beyond disruption of microtubule machinery that may be linked to its superior efficacy and less degree of toxicities. To date, only Phase III evidence to support eribulin use is in breast cancer, but the ongoing Phase III trial testing its efficacy in metastatic lung cancer against treatment of physician's choice will prove its merits in this setting.

Eribulin mesylate in heavily pretreated metastatic breast cancer patients: current practice in an Italian community hospital

AIM

The aim of this study is to report on the activity and safety of eribulin mesylate in a representative number of pretreated metastatic breast cancer (MBC) patients in current practice. Eribulin mesylate, a new microtubule inhibitor, is approved as monotherapy for the treatment of patients with locally advanced breast cancer or MBC who have progressed after at least two chemotherapeutic regimens for advanced disease.

PATIENTS & METHODS

From February to October 2012, 27 MBC patients, previously treated with anthracyclines and taxanes, were treated with 1.4 mg/m(2) intravenous infusion of eribulin mesylate at a community hospital.

RESULTS

Eight (30%) patients achieved partial response, one achieved complete response and three achieved stable disease. Median duration of response was 2.5 months (95% CI: 1.6-5.7; range: 1.3-5.7). Median overall survival was 8 months (95% CI: 6.1-9.7; range: 0.6-9.9). Reported adverse events were grade 1-2 asthenia (83%), peripheral sensory neuropathy (48%), nausea (37%) and neutropenia (30%).

CONCLUSION

Our retrospective analysis of a clinical practice experience supports the evidence that eribulin mesylate has clinical activity and provides acceptable benefit to heavily pretreated MBC.

Feasibility study of personalized peptide vaccination for metastatic recurrent triple-negative breast cancer patients

Introduction

Since treatment modalities for metastatic recurrent triple-negative breast cancer (mrTNBC) are limited, a novel treatment approach including immunotherapy is required. We have developed a novel regimen of personalized peptide vaccination (PPV), in which vaccine antigens are individually selected from a pool of different peptide candidates based on the pre-existing host immunity. Herein we conducted a phase II study of PPV for metastatic recurrent breast cancer patients to investigate the feasibility of PPV for mrTNBC.

Methods

Seventy-nine patients with metastatic recurrent breast cancer who had metastases and had failed standard chemotherapy and/or hormonal therapy were enrolled. They were subgrouped as the mrTNBC group (n = 18), the luminal/human epidermal growth factor receptor 2 (HER2)-negative group (n = 41) and the HER2-positive group (n = 18), while the remaining two patients had not been investigated. A maximum of four human leukocyte antigen (HLA)-matched peptides showing higher peptide-specific immunoglobulin G (IgG) responses in pre-vaccination plasma were selected from 31 pooled peptide candidates applicable for the four HLA-IA phenotypes (HLA-A2, -A24, or -A26 types, or HLA-A3 supertypes), and were subcutaneously administered weekly for 6 weeks and bi-weekly thereafter. Measurement of peptide-specific cytotoxic T lymphocyte (CTL) and IgG responses along with other laboratory analyses were conducted before and after vaccination.

Results

No severe adverse events associated with PPV were observed in any of the enrolled patients. Boosting of CTL and/or IgG responses was observed in most of the patients after vaccination, irrespective of the breast cancer subtypes. There were three complete response cases (1 mrTNBC and 2 luminal/HER2-negative types) and six partial response cases (1 mrTNBC and 5 luminal/HER2-negative types). The median progression-free survival time and median overall survival time of mrTNBC patients were 7.5 and 11.1 months, while those of luminal/HER2-negative patients were 12.2 and 26.5 months, and those of HER2-positive patients were 4.5 and 14.9 months, respectively.

Conclusions

PPV could be feasible for mrTNBC patients because of the safety, immune responses, and possible clinical benefits.

Clinical Trial Registration Number

UMIN000001844 (Registration Date: April 5, 2009)

Eribulin mesylate in breast cancer

Eribulin mesylate is a synthetic analog of halichondrin B (a polyether macrolide isolated from a marine sponge). It is a nontaxane microtubule dynamics inhibitor with a novel mechanism of action. It is the first drug that has demonstrated an improvement in overall survival as a single agent compared with the physician's choice of currently available treatments in locally advanced or metastatic breast cancer, previously treated with anthracyclines and taxanes. It has shown a good manageable tolerability profile. This drug has been approved by the US FDA and by the EMA for patients with locally advanced or metastatic breast cancer who have received at least two chemotherapeutic regimens for advanced/metastatic disease. Prior therapy should have included an anthracycline and a taxane in either the adjuvant or metastatic setting unless patients were not suitable for these treatments. The aim of this article is to describe the mechanism of action, pharmacokinetics, pharmacodynamics and the most relevant clinical trials in the development of this drug.

Population pharmacometric analyses of eribulin in patients with locally advanced or metastatic breast cancer previously treated with anthracyclines and taxanes

Pharmacometric investigation of eribulin was undertaken in patients with metastatic breast cancer (MBC) and other advanced solid tumors. A population pharmacokinetic (PK) model used data combined from seven phase 1 studies (advanced solid tumors; n = 129), and one phase 2 (MBC; n = 211), and one phase 3 study (MBC; n = 173). Phase 3 data were also used in a PK/pharmacodynamic (PD) model of efficacy and tumor response (sum of longest diameters of target lesions). All analyses used NONMEM 7.2. Eribulin PK, described by a dose-independent, three-compartment model with allometric relationship for body weight, was similar for all tumor types. Inter-individual variability (IIV) was 52% for both exposure and clearance. Liver function markers (albumin, alkaline phosphatase, bilirubin) significantly influenced eribulin PK (7.3% of IIV in clearance). Tumor shrinkage correlated with eribulin exposure; a 36% decrease in tumor size from baseline was modeled at week 36. No patient/disease factors significantly predicted eribulin's effect on tumor size. At week 6, a decrease in tumor size was associated with longer survival than an increase (P = .0055), suggesting survival may relate indirectly to eribulin exposure. These pharmacometric analyses provide a detailed overview of eribulin exposure-efficacy relationships to inform physicians treating patients with MBC.

[Search for natural substances with therapeutic activity: George R. Pettit]

This series of brief reviews covers the "life and work" of famous and iconic researchers who discovered major therapeutics from natural products: their life history, the circumstances of their discoveries, the molecules and their molecular, cellular and physiological mechanisms of action, and their biomedical applications. Dedicated to George R. Pettit, the second article reviews the life of the famous researcher, his worldwide exploration of natural products, especially of marine origin, in search of promising anticancer leads, his discovery and structural elucidation of very potent drug candidates, their synthesis and the launch of some of them on the pharmaceutical market. An extraordinary scientific career which lead George R. Pettit from exploration of Nature to state-of-the-art analytical and synthetic chemistry and from clinical trials to therapeutic successes.

Tubulin: an example of targeted chemotherapy

Anticancer drugs directed against the microtubule, including taxanes and vinca alkaloids, have been the backbone of many chemotherapy regimes for decades. These drugs have, however, significant limitations, which have prompted the development of novel microtubule targeting agents (MTAs). This article will discuss MTAs for anticancer therapies and recent debates regarding their mechanisms of action. Furthermore, the limitations of taxanes, including hypersensitivity reactions, neurotoxicity, drug resistance and lack of validated biomarkers to guide therapy will be discussed, all of which have driven the development of novel agents. The mechanisms of action and drug development of new generations of MTAs will also be outlined. Agents demonstrating utility in Phase III clinical trials, including eribulin, ixabepilone, cabazitaxel and trastuzumab-DM1 will be highlighted, as well as novel agents currently in development and future directions for MTAs.

Finding chemo: the search for marine-based pharmaceutical drugs active against cancer

OBJECTIVES

Cancer affects the health of many people globally. The most common treatment that is used for cancer is chemotherapy, which has shown promising results but not without side effects. Some of these side effects jeopardise further treatment, and this eventually leads to advanced stages of malignancy and mortality. As a result, there is a need for better and safer anticancer compounds such as those found naturally. One of the most abundant natural environments to find such compounds is the sea, and this vast resource has been biomined since the 1950s.

KEY FINDINGS

There are currently three marine anticancer agents marketed (Yondelis, Cytosar-U and Halaven), with several others undergoing clinical trials. This review discusses marine-derived products in clinical use and in clinical trials, and discusses available literature on the growth suppression or pro-apoptotic properties of these compounds, and the molecular mechanisms underpinning these cell biological phenomena.

SUMMARY

The marine environment may hold promising anticancer compounds within its depths, warranting further research to be performed in this area, albeit with respect for the natural ecosystems that are being explored for drug discover and subsequently used for drug development.

Ethyl acetate extract of the Mauritian sponge Jaspis sp. induces cell arrest in human promyelocytic leukemia cells

Marine sponges are considered as a gold mine of new natural products possessing numerous biological activities. We examined the cytotoxic properties of the ethyl acetate extract (JDE) of the previously unrecorded sponge, Jaspis sp. collected from Mauritius Waters. JDE displayed an interesting IC50 of 0.057±0.04μg/mL on HL-60 cells evaluated by MTS assay. Mitochondrial membrane potential change, microscopic analysis and DNA fragmentation assays also confirmed JDE induced apoptosis on HL-60 cells. Annexin V staining demonstrated that JDE induced apoptosis at different concentrations. Treatment with 100ng/mL of JDE led to an accumulation of cells in G2/M phase after 24 h, causing a significant increase of cells (24h: 5.84%; 48h: 13.41%) in sub-G1 phase suggesting that JDE can induce cell cycle arrest in G2/M phase.

Eribulin for advanced breast cancer: a drug evaluation

Eribulin is a synthetic microtubule dynamics inhibitor that was developed from a marine natural product halichondrin B. It exhibited in vitro and in vivo activities against a wide number of malignancies. A number of advanced phase trials showed improved survival following eribulin treatment in pretreated advanced breast cancer patients. This review provides an overview of the background to the therapeutic use of eribulin in oncology, including its pharmacology, pharmacokinetics, clinical efficacy, safety, and potential economic factors.

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.

Cytotoxic activities of hexane, ethyl acetate and butanol extracts of marine sponges from Mauritian Waters on human cancer cell lines

The ocean is an exceptional source of natural products with many of them exhibiting novel structural features and bioactivity. As one of the most interesting phylum with respect to pharmacological active marine compounds, Poriferas have been investigated widely in the last few decades. A total of 60 organic extracts (hexane, ethyl acetate and butanol) from 20 species of marine sponges from Mauritius were screened at 50μg/ml in an in vitro screening assay against 9 human cancer cell lines. From these tested extracts, many exhibited pronounced cytotoxic effect at least in one of the cell lines and cell type cytotoxic specificity was observed. 27% of ethyl acetate, 11% of hexane and 2% of butanol extracts were found to possess a cytotoxicity ≥75% on 9 different cancer cell lines with the sponges Petrosia sp. 1, Petrosia sp. 2, Pericharax heteroraphis and Jaspis sp. being the most active. Overall, the HL-60cells were much more sensitive to most of the extracts than the other cell lines. We further evaluated the properties of the ethyl acetate (JDE) and hexane extract (JDH) of one sponge, Jaspis sp. on KB cells. JDE displayed a smaller IC(50) than JDH. Clonogenic assay confirmed the antiproliferative effect of both extracts while mitochondrial membrane potential change and microscopic analysis demonstrated extracts-induced apoptosis. Treatment with 100ng/ml of JDE led to a significant increase of cells (24h: 4.02%; 48h: 26.23%) in sub-G1 phase. The cytotoxic properties of the tested extracts from these sponges suggest the presence of compounds with pharmacological potential and are currently undergoing fractionation to isolate the active constituents.

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.

Treating metastatic breast cancer with systemic chemotherapies: current trends and future perspectives

Treatment selection for metastatic breast cancer (MBC) is guided by multiple factors, most importantly hormone receptor (HR) or HER2 expression, treatment history, and prognostic factors such as short disease-free interval, presence of visceral metastases, performance status, and degree of symptoms. Chemotherapy is indicated as initial therapy for patients with HR-negative disease and following failure of hormonal therapies in HR-positive disease. Patients treated with an anthracycline or a taxane in early-stage settings may no longer be candidates for those drugs in MBC, thus underscoring the need for alternative options. Sequential single-agent therapy or combination therapy are viable strategies. Trials have shown that ixabepilone plus capecitabine significantly improves progression-free survival compared with capecitabine alone in anthracycline- or taxane-pretreated or -resistant patients, and single-agent eribulin improves survival compared with the physician's choice of treatment in patients treated previously with at least two regimens for MBC. Regardless of the regimen, proactive management to detect treatment-related adverse events in a timely manner remains important for ensuring effective delivery of treatment. Many promising investigational agents are in development, including T-DM1 (trastuzumab emtansine) and pertuzumab for HER2-positive disease, as well as PARP-1 (poly[adenosine diphosphate ribose] polymerase-1) inhibitors and cetuximab for triple-negative disease. In addition, new options for the treatment of MBC following failure of an anthracycline and a taxane promise to improve patient outcomes. Nurses should remain vigilant for adverse events and remember that the goal of treatment remains control of the disease and palliation.

Proposal for a novel methodology to screen and score cost versus survival for anticancer drugs in metastatic disease: could cost weigh in evaluation?

PURPOSE

Rising costs of anticancer drugs prompt concerns about their approval, use, and affordability. A methodology was developed to evaluate cost versus survival for anticancer drugs in metastatic breast cancer and non-small-cell lung cancer (NSCLC).

METHODS

Costs of evaluated drugs were calculated by using average wholesale prices in US dollars. Ratios of cost to day of survival (cost/survival/d) were obtained by dividing costs of the entire treatment by reported median survival gain in days. A crude score of 100% was assigned to a cost/survival/d of less than $25, and 0% to a cost/survival/d of more than $750. A strategy was designed to correct for overall survival (OS) versus progression-free survival (PFS), adverse effects, and quality of life.

RESULTS

In breast cancer, PFS scores of bevacizumab varied between 0% and 60%. In NSCLC, OS scores of bevacizumab improved from 0% to 50%, as a result of histology, lower prices, and extended therapy. Gefitinib and erlotinib PFS scores were 80% and 70%, respectively. Correction for longer survival with erlotinib resulted in similar scores. In maintenance therapy, the OS score for pemetrexed was 70% as compared with 25% for erlotinib. Generic drugs scored 70% to 90%.

CONCLUSION

Cost/survival varied with the number of cycles. In breast cancer, bevacizumab scores failed to justify its use. In NSCLC, 10 cycles of bevacizumab scored 0%. Scores improved with extended treatment and lower prices. Scores for gefitinib and erlotinib would support their approval. Erlotinib was preferred because of longer PFS. Results tended to endorse maintenance pemetrexed but not erlotinib. Generic drugs demonstrated high scores. Cost/survival could weigh in drug evaluation.

Carcinomatous pericarditis in 3 breast cancer patients with long-term survival

With advances in drug treatment of breast cancer, the number of patients experiencing cardiac toxicity or carcinomatous pericarditis is expected to increase. These conditions can cause cardiac tamponade, which is a potentially fatal condition requiring prompt diagnosis and treatment. We experienced 3 breast cancer patients with cardiac tamponade due to carcinomatous pericarditis who survived for prolonged periods after treatment with pericardiocentesis and intrapericardial instillation. The 3 women were 68, 46 and 46 years old, respectively, and receiving treatment for recurrent breast cancer after surgery. They developed dyspnea and cough and were diagnosed with cardiac tamponade by echocardiography. Pericardiocentesis was performed, and cytology of the effusion confirmed the diagnosis of carcinomatous pericarditis. Intrapericardial instillation of cisplatin reduced the cardiac effusion, ameliorating symptoms. The patients died 13, 31 and 14 months later, respectively. In our clinical review of 13 other cases of cardiac tamponade due to breast cancer, 85% achieved local control after the aforementioned local treatments, which were considered to be effective. Although the overall prognosis was poor with a median survival time of only 4 months, some patients were able to survive more than 1 year after local treatment with subsequent systemic therapy.