Pooled analyses of eribulin in metastatic breast cancer patients with at least one prior chemotherapy

Datopotamab Deruxtecan Versus Chemotherapy in Previously Treated Inoperable/Metastatic Hormone Receptor-Positive Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer: Primary Results From TROPION-Breast01

PURPOSE

The global, phase 3, open-label, randomized TROPION-Breast01 study assessed the trophoblast cell surface antigen 2-directed antibody-drug conjugate datopotamab deruxtecan (Dato-DXd) versus investigator's choice of chemotherapy (ICC) in hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) breast cancer.

METHODS

Adult patients with inoperable/metastatic HR+/HER2‒ breast cancer, who had disease progression on endocrine therapy, for whom endocrine therapy was unsuitable, and had received one to two previous lines of chemotherapy in the inoperable/metastatic setting, were randomly assigned 1:1 to Dato-DXd (6 mg/kg once every 3 weeks) or ICC (eribulin/vinorelbine/capecitabine/gemcitabine). Dual primary end points were progression-free survival (PFS) by blinded independent central review (BICR) and overall survival (OS).

RESULTS

Patients were randomly assigned to Dato-DXd (n = 365) or ICC (n = 367). Dato-DXd significantly reduced the risk of progression or death versus ICC (PFS by BICR hazard ratio [HR], 0.63 [95% CI, 0.52 to 0.76]; P < .0001). Consistent PFS benefit was observed across subgroups. Although OS data were not mature, a trend favoring Dato-DXd was observed (HR, 0.84 [95% CI, 0.62 to 1.14]). The rate of grade ≥3 treatment-related adverse events (TRAEs) with Dato-DXd was lower than ICC (20.8% v 44.7%). The most common TRAEs (any grade; grade ≥3) were nausea (51.1%; 1.4%) and stomatitis (50%; 6.4%) with Dato-DXd and neutropenia (grouped term, 42.5%; 30.8%) with ICC.

CONCLUSION

Patients receiving Dato-DXd had statistically significant and clinically meaningful improvement in PFS and a favorable and manageable safety profile, compared with ICC. Results support Dato-DXd as a novel treatment option for patients with inoperable/metastatic HR+/HER2‒ breast cancer who have received one to two previous lines of chemotherapy in this setting.

Eribulin in breast cancer: Current insights and therapeutic perspectives

Eribulin is a non-taxane synthetic analogue approved in many countries as third-line treatment for the treatment of patients with metastatic breast cancer. In addition to its mitotic property, eribulin has non-mitotic properties including but not limited to, its ability to induce phenotypic reversal of epithelial to mesenchymal transition, vascular remodelling, reduction in immunosuppressive tumour microenvironment. Since approval, there has been a surge in studies investigating the application of eribulin as an earlier-line treatment and also in combination with other agents such as immunotherapy and targeted therapy across all breast cancer sub-types, including hormone receptor positive, HER2 positive and triple negative breast cancer, many demonstrating promising activity. This review will focus on the application of eribulin in the treatment of metastatic breast cancer across all subtypes including its role as an earlier-line agent, its toxicity profile, and potential future directions.

Subgroup analyses from the phase 3 ASCENT study of sacituzumab govitecan in metastatic triple-negative breast cancer

In this post hoc analysis of the ASCENT study, we compared outcomes with sacituzumab govitecan (SG) vs single-agent chemotherapy in clinically important subgroups of patients with metastatic triple-negative breast cancer (mTNBC). Patients with mTNBC refractory to/relapsing after ≥2 prior chemotherapies (≥1 in the metastatic setting) were randomized 1:1 to receive SG or treatment of physician's choice (TPC) until unacceptable toxicity/progression. The primary endpoint was progression-free survival (PFS) per RECIST 1.1 by central review in patients without brain metastases. Patients with brain metastases were allowed if metastases were stable ≥4 weeks. In the intention-to-treat (ITT) population, 19% of patients were age ≥65 years; 12% were Black, and 12% had brain metastases. SG improved PFS and overall survival (OS), respectively, vs TPC in patients age ≥65 years (7.1 vs 2.4 months and 14.7 vs 8.9 months), or of Black race (5.4 vs 2.2 months and 13.8 vs 8.5 months), consistent with outcomes in the ITT population. Patients with brain metastases had numerically higher median PFS with SG vs TPC, but median OS was similar between treatment groups. SG was well tolerated and had a manageable safety profile consistent with the full safety population across all subgroups; neutropenia and diarrhea were the most common treatment-emergent adverse events. These findings confirm the meaningful clinical benefit of SG vs standard chemotherapy in patient subgroups with high unmet needs. SG should be considered an effective and safe treatment option for patients with mTNBC eligible for second-line or later therapy. ClinicalTrials.gov Number: NCT02574455.

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.

TROPION-Breast01: Datopotamab deruxtecan vs chemotherapy in pre-treated inoperable or metastatic HR+/HER2- breast cancer

Improving the prognosis for patients with metastatic HR+/HER2- breast cancer remains an unmet need. Patients with tumors that have progressed on endocrine therapy and/or are not eligible for endocrine therapy had limited treatment options beyond chemotherapy. Antibody-drug conjugates are a novel and promising treatment class in this setting. Datopotamab deruxtecan (Dato-DXd) consists of a TROP2-directed humanized IgG1 monoclonal antibody attached via a serum-stable cleavable linker to a topoisomerase I inhibitor payload. TROPION-Breast01 is an ongoing phase III study that is evaluating the efficacy and safety of Dato-DXd compared with investigator's choice of standard-of-care chemotherapy in patients with inoperable or metastatic HR+/HER2- breast cancer who have received one or two prior lines of systemic chemotherapy in the inoperable or metastatic setting. Clinical Trial Registration: NCT05104866 (ClinicalTrials.gov).

Challenges in HER2-low breast cancer identification, detection, and treatment

Recently, human epidermal growth factor receptor 2 (HER2)-low breast cancer (BC) has emerged as a novel subset within the category of HER2-negative BC, prompting a reassessment of the immunohistochemical negative scores of 0, 1+, and the 2+/in situ hybridization (ISH) negative phenotype. Recent clinical trials have provided compelling evidence of the substantial clinical advantages offered by novel antibody-drug conjugates (ADCs) that target HER2 in the treatment of these specific tumor cohorts. Notably, trastuzumab deruxtecan (T-Dxd), an ADC that specifically targets HER2, has recently received approval from the US Food and Drug Administration as the inaugural targeted therapeutic option for HER2-low BC. However, the classification of HER2-low BC as a distinct subtype, the methods for detecting HER2-low BC, and the optimal treatment approach for HER2-low BC remain subjects of ongoing debate and lack consensus. This comprehensive review aims to address these pertinent concerns, offering insights into the nuanced tumor biology underlying HER2-low BC and critically analyzing the current treatment pathways available. By synthesizing available evidence, the objective is to contribute to an enhanced understanding of HER2-low BC, providing a foundation for more informed clinical decisions and further advancements in tailored therapeutic approaches. As the medical community navigates these uncertainties, this review seeks to consolidate existing knowledge, fostering a collective effort toward establishing consensus in the diagnosis and treatment of HER2-low BC.

A phase Ib/II study of eribulin in combination with cyclophosphamide in patients with advanced breast cancer

PURPOSE

We hypothesized that eribulin combined with cyclophosphamide (EC) would be an effective combination with tolerable toxicity for the treatment of advanced breast cancer (ABC).

METHODS

Patients with histologically confirmed metastatic or unresectable ABC with any number of prior lines of therapy were eligible to enroll. In the dose escalation cohort, dose level 0 was defined as eribulin 1.1 mg/m2 and cyclophosphamide 600 mg/m2, and dose level 1 was defined as eribulin 1.4 mg/m2 and cyclophosphamide 600 mg/m2. Eribulin was given on days 1 and 8 and cyclophosphamide on day 1 of a 21-day cycle. In the dose expansion cohort, enrollment was expanded at dose level 1. The primary objective was clinical benefit rate (CBR), and secondary objectives were response rate (RR), duration of response (DOR), progression-free survival (PFS), and safety.

RESULTS

No dose-limiting toxicities were identified in the dose escalation cohort (n = 6). In the dose expansion cohort, an additional 38 patients were enrolled for a total of 44 patients, including 31 patients (70.4%) with hormone receptor-positive (HR +)/HER2- disease, 12 patients (27.3%) with triple-negative breast cancer (TNBC), and 1 patient (2.3%) with HR + /HER2 + disease. Patients had a median age of 56 years (range 33-82 years), 1 prior line of hormone therapy (range 0-6), and 2 prior lines of chemotherapy (range 0-7). CBR was 79.5% (35/44; 7 partial response, 28 stable disease) and the median DOR was 16.4 weeks (range 13.8-21.1 weeks). Median PFS was 16.4 weeks (95% CI: 13.8-21.1 weeks). The most common grade 3/4 adverse event was neutropenia (47.7%, n = 21). Fourteen of 26 patients (53.8%) with circulating tumor cell (CTC) data were CTC-positive ([Formula: see text] 5 CTC/7.5 mL) at baseline. Median PFS was shorter in patients who were CTC-positive vs. negative (13.1 vs 30.6 weeks, p = 0.011).

CONCLUSION

In heavily pretreated patients with ABC, treatment with EC resulted in an encouraging CBR of 79.5% and PFS of 16.4 weeks, which compares favorably to single-agent eribulin. Dose reduction and delays were primarily due to neutropenia. The contribution of cyclophosphamide to eribulin remains unclear but warrants further evaluation. NCT01554371.

TROPION-Breast02: Datopotamab deruxtecan for locally recurrent inoperable or metastatic triple-negative breast cancer

Despite recent treatment advances, the prognosis for patients with locally recurrent inoperable or metastatic triple-negative breast cancer (TNBC) remains poor. The antibody-drug conjugate datopotamab deruxtecan (Dato-DXd) is composed of a humanized anti-TROP2 IgG1 monoclonal antibody linked to a topoisomerase I inhibitor payload via a stable, cleavable linker. The phase III TROPION-Breast02 trial in patients previously untreated for locally recurrent inoperable or metastatic TNBC, who are not candidates for PD-1/PD-L1 inhibitors is evaluating efficacy and safety of Dato-DXd versus investigator's choice of chemotherapy (ICC). Approximately 600 patients will be randomized 1:1 to Dato-DXd 6 mg/kg iv. every 3 weeks or ICC (paclitaxel, nab-paclitaxel, carboplatin, capecitabine or eribulin mesylate). Dual primary end points are progression-free survival by blinded independent central review and overall survival.

Cost-effectiveness of sacituzumab govitecan versus chemotherapy in patients with relapsed or refractory metastatic triple-negative breast cancer

BACKGROUND

The effectiveness of sacituzumab govitecan for metastatic triple-negative breast cancer (TNBC) has been reported in recent research, however, the value of the effectiveness and cost of sacituzumab govitecan is still unclear.

METHODS

A microsimulation model was developed using data from the ASCENT trial to assess the cost-effectiveness of sacituzumab govitecan for patients with relapsed or refractory metastatic TNBC over a lifetime. Model inputs, including clinical data, patient characteristics, and direct medical costs, were based on the ASCENT trial, public databases, and published literature. The primary outcomes of the model were the incremental cost-effectiveness ratio (ICER) and quality-adjusted life-years (QALYs). Univariate and probabilistic sensitivity analysis (PSA) and multiple scenario analyses were performed to address the uncertainty of the model.

RESULTS

Our results revealed that sacituzumab govitecan versus chemotherapy costs $293,037 and yielded an additional 0.2340 of QALYs in the whole population with metastatic TNBC, leading to an ICER of $1,252,295 gained. And in the population with metastatic TNBC without brain metastasis, the sacituzumab govitecan versus chemotherapy costs $309,949 and obtained an extra 0.2633 of QALYs, which resulted in an ICER of $1,177,171/QALYs. Univariate analyses indicated that the model outcomes were most sensitive to the drug cost of sacituzumab govitecan, the utility of progression-free disease, and the utility of progressed disease.

CONCLUSION

From the US payer perspective, sacituzumab govitecan is unlikely to be a cost-effective option for patients with relapsed or refractory metastatic TNBC compared with chemotherapy. Based on the value standpoint, a price decrease of sacituzumab govitecan is expected to increase the cost-effectiveness of sacituzumab govitecan in patients with metastatic TNBC.

A phase Ib study of TQB2450 plus anlotinib in patients with advanced triple-negative breast cancer

This study explored the safety and preliminary efficacy of the anti-PD-L1 antibody TQB2450 combined with the multi-kinase inhibitor anlotinib in advanced triple-negative breast cancer (TNBC). Patients with advanced TNBC who received at least one line of systemic therapy with anthracyclines and/or taxanes were enrolled in the dose-escalation and dose-expansion cohorts. Between May 29, 2019 and September 28, 2020, 34 patients were enrolled (three in the dose-escalation cohort and 31 in the dose-expansion cohort). The ORR was 26.5% (95% CI, 12.9-44.4) and the DCR was 73.5% (95% CI, 55.6-87.1). The median PFS was 5.6 (95% CI, 2.9-7.5) months, and the median OS was not reached. Seventeen (50.0%) patients had grade ≥3 treatment-related adverse events, with the most common being QT interval prolongation (17.6%) and hypertension (14.7%). No treatment-related deaths occurred. TQB2450 combined with anlotinib as a chemotherapy-free treatment shows promising efficacy with a manageable safety profile for patients with previously treated advanced TNBC.

Cost-effectiveness of trastuzumab deruxtecan in previously treated human epidermal growth factor receptor 2-low metastatic breast cancer

Background

Results from DESTINY-Breast04 trial revealed that trastuzumab deruxtecan (T-DXd) improved both progression-free survival and overall survival for patients with human epidermal growth factor receptor 2 (HER2)-low metastatic breast cancer (mBC). However, the economic impact of this practice remains unclear. The purpose of this study was to evaluate the cost-effectiveness of T-DXd on HER2-low mBC from the viewpoint of U.S. payers.

Methods

Using the clinical data from the DESTINY-Breast04 trial, a three-state Markov model was created to assess the economic and health effects of T-DXd versus chemotherapy. The incremental cost-effectiveness ratio (ICER) and willingness-to-pay threshold were determined and compared. One-way and probabilistic sensitivity analysis were used to measure parameter uncertainty.

Results

In the overall HER2-low population, T-DXd provided additional 0.47 quality-adjusted life-years (QALYs) at an increased cost of $149,222 compared with chemotherapy, yielding an ICER of $317,494/QALY. The ICER was $353,903/QALY in the hormone receptor (HR)-positive subgroup, which decreased to $259,825/QALY in the HR-negative subgroup. The sensitivity analysis found that T-DXd would not be cost-effective in the base-case. The expected cost of T-DXd will be less than $4,281/cycle ($11.33/mg) or $1,903/cycle ($5.03/mg) to achieve a 50 or 90% cost-benefit probability, respectively.

Conclusions

T-DXd provides significant health benefit for patients with HER2-low mBC compared with chemotherapy but is unlikely to be cost-effective in the United States.

Sacituzumab Govitecan in Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Metastatic Breast Cancer

PURPOSE

Hormone receptor-positive (HR+) human epidermal growth factor receptor 2-negative (HER2-) endocrine-resistant metastatic breast cancer is treated with sequential single-agent chemotherapy with poor outcomes. Sacituzumab govitecan (SG) is a first-in-class antibody-drug conjugate with an SN-38 payload targeting trophoblast cell-surface antigen 2, an epithelial antigen expressed in breast cancer.

METHODS

In this global, randomized, phase III study, SG was compared with physician's choice chemotherapy (eribulin, vinorelbine, capecitabine, or gemcitabine) in endocrine-resistant, chemotherapy-treated HR+/HER2- locally recurrent inoperable or metastatic breast cancer. The primary end point was progression-free survival (PFS) by blinded independent central review.

RESULTS

Patients were randomly assigned to receive SG (n = 272) or chemotherapy (n = 271). The median age was 56 years, 95% had visceral metastases, and 99% had a prior cyclin-dependent kinase 4/6 inhibitor, with three median lines of chemotherapy for advanced disease. Primary end point was met with a 34% reduction in risk of progression or death (hazard ratio, 0.66 [95% CI, 0.53 to 0.83; P = .0003]). The median PFS was 5.5 months (95% CI, 4.2 to 7.0) with SG and 4.0 months (95% CI, 3.1 to 4.4) with chemotherapy; the PFS at 6 and 12 months was 46% (95% CI, 39 to 53) v 30% (95% CI, 24 to 37) and 21% (95% CI, 15 to 28) v 7% (95% CI, 3 to 14), respectively. Median overall survival (first planned interim analysis) was not yet mature (hazard ratio, 0.84; P = .14). Key grade ≥ 3 treatment-related adverse events (SG v chemotherapy) were neutropenia (51% v 38%) and diarrhea (9% v 1%).

CONCLUSION

SG demonstrated statistically significant PFS benefit over chemotherapy, with a manageable safety profile in patients with heavily pretreated, endocrine-resistant HR+/HER2- advanced breast cancer and limited treatment options.

Sacituzumab govitecan as second-line treatment for metastatic triple-negative breast cancer-phase 3 ASCENT study subanalysis

Patients with triple-negative breast cancer (TNBC) who relapse early after (neo)adjuvant chemotherapy have more aggressive disease. In the ASCENT trial, sacituzumab govitecan (SG), an antibody-drug conjugate composed of an anti-Trop-2 antibody coupled to SN-38 via a hydrolyzable linker, improved outcomes over single-agent chemotherapy of physician's choice (TPC) in metastatic TNBC (mTNBC). Of 468 patients without known baseline brain metastases, 33/235 vs 32/233 patients (both 14%) in the SG vs TPC arms, respectively, received one line of therapy in the metastatic setting and experienced disease recurrence ≤12 months after (neo)adjuvant chemotherapy. SG prolonged progression-free survival (median 5.7 vs 1.5 months [HR, 0.41; 95% CI, 0.22-0.76]) and overall survival (median 10.9 vs 4.9 months [HR, 0.51; 95% CI, 0.28-0.91]) vs TPC, with a manageable safety profile in this subgroup consistent with the overall population. In this second-line setting, as with later-line therapy, SG improved survival over conventional chemotherapy for patients with mTNBC.

Major advancements in metastatic breast cancer treatment: when expanding options means prolonging survival

In the last years we have witnessed tremendous advancements in the treatment landscape of metastatic breast cancer (MBC), leading to a progressive prolongation of progression-free survival and, in some cases, also of overall survival. This led to a substantial increase of advanced disease treatability. In the present review we comprehensively and critically describe the most significant progresses in the therapeutic scenario of MBC according to BC subtype. In particular, we reviewed studies reporting practice-changing data in hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative, HER2-positive and triple-negative BC, with also a hint to BRCA-related tumors and the emerging HER2-low-positive category.

Emerging strategies for TNBC with early clinical data: new chemoimmunotherapy strategies

PURPOSE

The use of immune checkpoint inhibitors in combination with chemotherapy for the treatment of triple-negative breast cancer is becoming more widespread as efficacy data accumulates. However, outcomes remain less than optimal and not all patients benefit from treatment. The aim of this article is to review the emerging chemoimmunotherapy strategies for triple-negative breast cancer.

METHODS

Searches were undertaken on Pubmed and Clinicaltrials.gov for relevant publications and trials.

RESULTS

Preclinical and clinical data have provided insights into the differing immunomodulatory effects of chemotherapy agents, highlighting the immunostimulatory properties of anthracyclines. Mechanisms of resistance to immune checkpoint inhibition are discussed and the potential role of phosphatidylinositol 3-kinase (PI3K)/AKT and MAPK/ERK kinase (MEK) inhibitors in overcoming resistance. Finally, the emerging therapeutic class of antibody-drug conjugates for triple-negative breast cancer in combination with immune checkpoint inhibitors is reviewed.

CONCLUSIONS

The type and sequence of chemotherapy agents play an important role in optimising the response to immune checkpoint inhibitors. Antibody-drug conjugates in combination with immune checkpoint inhibitors are a promising area of development.

Eribulin improved the overall survival from the initiation of first-line chemotherapy for HER2-negative advanced breast cancer: a multicenter retrospective study

Background

Eribulin methylate (eribulin) improved the overall survival (OS) of eribulin-treated patients with HER2-negative advanced breast cancer (ABC) in prospective and retrospective studies. However, the effect of eribulin on OS as first-line chemotherapy and the characteristics of the patients who benefited from eribulin remain unclear.

Methods

Between January 2011 and December 2016, 301 patients with HER2-negative ABC who started first-line chemotherapy at 3 institutions were retrospectively evaluated for OS from the initiation of first-line chemotherapy.

Results

We identified 172 patients (119 estrogen receptor-positive [ER+], 47 ER−, 6 unknown) who received eribulin (eribulin group) and 129 patients (92 ER+, 31 ER−, 6 unknown) who did not receive eribulin (non-eribulin group). The median OS from the initiation of first-line chemotherapy in the two groups was not statistically significant (869 vs. 744 days, P = 0.47, log-rank); however, in patients who received eribulin in later lines (≥3rd-line) and who had a history of perioperative chemotherapy with anthracycline- and/or taxane-based regimens, the median OS improved (1001 vs. 744 days, P = 0.037; and 834 vs. 464 days, respectively P = 0.032, respectively; Wilcoxon). Multivariate analyses revealed that a history of perioperative chemotherapy with anthracycline- and/or taxane-based regimens was a predictive factor (hazard ratio, 0.39; 95% confidence interval, 0.21–0.70) for OS.

Conclusions

This study successfully identified subgroups of HER2− ABC patients with improved OS by eribulin therapy. Selecting patients according to their background and line of treatment will maximize the efficacy of eribulin therapy.

Comparative review of pharmacological therapies in individuals with HER2-positive advanced breast cancer with focus on hormone receptor subgroups

Breast cancer is the fifth leading cause of cancer-related deaths worldwide. The randomized controlled trials (RCTs) of targeted therapies in human epidermal receptor 2 (HER2)-positive advanced breast cancer (ABC) have provided an evidence base for regulatory and reimbursement agencies to appraise the use of cancer therapies in clinical practice. However, a subset of these patients harbor additional biomarkers, for example, a positive hormone receptor status that may be more amenable to therapy and improve overall survival (OS). This review seeks to explore the reporting of evidence for treatment effects by the hormone receptor status using the RCT evidence of targeted therapies for HER2-positive ABC patients. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed to identify published RCTs. Extracted data were synthesized using network meta-analysis to obtain the relative effects of HER2-positive-targeted therapies. We identified a gap in the reporting of the effectiveness of therapies by the hormone receptor status as only 15 out of 42 identified RCTs reported hormone receptor subgroup analyses; the majority of which reported progression-free survival but not OS or the overall response rate. In conclusion, we recommend that future trials in ABC should report the effect of cancer therapies in hormone receptor subgroups for all outcomes.

Prioritising systemic cancer therapies applying ESMO’s tools and other resources to assist in improving cancer care globally: the Kazakh experience

Background

In Kazakhstan, cancer is the second leading cause of death with a major public health and economic burden. In the last decade, cancer care and cancer medicine costs have significantly increased. To improve the efficiency and efficacy of cancer care expenditure and planning, the Kazakhstan Ministry of Health requested assistance from the World Health Organization (WHO) and the European Society for Medical Oncology (ESMO) to review its systemic cancer treatment protocols and essential medicines list and identify high-impact, effective regimens.

Materials and methods

ESMO developed a four-phase approach to review Kazakhstan cancer treatment protocols: (i) perform a systematic analysis of the country’s cancer medicines and treatment protocols; (ii) cross-reference the country’s cancer protocols with the WHO Model List of Essential Medicines, the ESMO-Magnitude of Clinical Benefit Scale and the European Medicines Agency’s medicine availability and indications database; (iii) extract treatment recommendations from the ESMO Clinical Practice Guidelines; (iv) expert review for all cancer medicines not on the WHO Model List of Essential Medicines and the country treatment protocols.

Results

This ESMO four-phase approach led to the update of the Kazakhstan national essential cancer medicines list and the list of cancer treatment protocols. This review has led to the withdrawal of several low-value or non-evidence-based medicines and a budget increase for cancer care to include all essential and highly effective medicines and treatment options.

Conclusion

When applied effectively, this four-phase approach can improve access to medicines, efficiency of expenditure and sustainability of cancer systems. The WHO–ESMO collaboration illustrated how, by sharing best practices, tools and resources, we can address access to cancer medicines and positively impact patient care.

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In Kazakhstan, from 2009 to 2019, there was a significant increase in costs of cancer care and cancer medicines.

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ESMO, under the guidance of WHO, reviewed the Kazakh cancer treatment protocols and national essential medicines list.

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The ESMO four-phase approach helped Kazakhstan in prioritising the most effective and high-impact cancer medicines.

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This approach can be applied in the evaluation of any national formulary as it uses open-access, evidence-based references.

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This collaboration is an example of how we can improve access to cancer medicines and positively impact patient care.

Analysis of patients without and with an initial triple-negative breast cancer diagnosis in the phase 3 randomized ASCENT study of sacituzumab govitecan in metastatic triple-negative breast cancer

PURPOSE

Sacituzumab govitecan (SG) is an antibody-drug conjugate composed of an anti-Trop-2 antibody coupled to SN-38 via a proprietary hydrolyzable linker. In the ASCENT study, SG improved survival versus single-agent treatment of physician's choice (TPC) in pre-treated metastatic triple-negative breast cancer (mTNBC). Hormone/HER2 receptor changes are common, particularly at relapse/metastasis. This subanalysis assessed outcomes in patients who did/did not have TNBC at initial diagnosis, before enrollment.

METHODS

TNBC diagnosis was only required at study entry. Patients with mTNBC refractory/relapsing after ≥ 2 prior chemotherapies were randomized 1:1 to receive SG or TPC. Primary endpoint was progression-free survival (PFS) in patients without brain metastases.

RESULTS

Overall, 70/235 (30%) and 76/233 (33%) patients who received SG and TPC, respectively, did not have TNBC at initial diagnosis. Clinical benefit with SG versus TPC was observed in this subset. Median PFS was 4.6 versus 2.3 months (HR 0.48; 95% CI 0.32-0.72), median overall survival was 12.4 versus 6.7 months (HR 0.44; 95% CI 0.30-0.64), and objective response rate (ORR) was 31% versus 4%; those who also received prior CDK4/6 inhibitors had ORRs of 21% versus 5%. Efficacy and safety for patients with TNBC at initial diagnosis were generally similar to those who did not present with TNBC at initial diagnosis.

CONCLUSION

Patients without TNBC at initial diagnosis had improved clinical outcomes and a manageable safety profile with SG, supporting SG as a treatment option for mTNBC regardless of subtype at initial diagnosis. Subtype reassessment in advanced breast cancer allows for optimal treatment. Clinical trial registration number NCT02574455, registered October 12, 2015.

Shorter duration of first-line chemotherapy reflects poorer outcomes in patients with HER2-negative advanced breast cancer: a multicenter retrospective study

Post-progression survival affects overall survival (OS) in patients with HER2-negative advanced breast cancer (HER2-ABC); thus, the optimal choice of first-line chemotherapy (1LCT) remains controversial. We investigated patients with HER2-ABC focusing on their sensitivity to 1LCT. We retrospectively analyzed patients with HER2-ABC who received 1LCT between January 2011 and December 2016 in three participating institutions. We identified 149 patients in the shorter and 152 patients in the longer time to treatment failure (TTF) groups. The median OS was significantly longer in the longer TTF group (hazard ratio [HR] 0.44, P < 0.001, log-rank). In the shorter TTF group, OS of patients who received paclitaxel plus bevacizumab (PB) therapy was significantly inferior to that of those who received chemotherapy other than PB (HR 2.57, P < 0.001, log-rank), and subsequent eribulin therapy significantly improved OS from 1LCT initiation (Wilcoxon P < 0.001); multivariate analyses showed that 1LCT PB therapy was an independent risk factor for poorer OS (HR 2.05, P = 0.003), while subsequent eribulin therapy was an independent prognostic factor for better OS (HR 0.56, P = 0.004). OS was significantly poorer in patients with HER2-ABC with a shorter duration of 1LCT, including PB therapy, while subsequent eribulin therapy improved OS.

The Place of Chemotherapy in The Evolving Treatment Landscape for Patients With HR-positive/HER2-negative MBC

Endocrine therapy (ET) for the treatment of patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR-positive/HER2-negative) metastatic breast cancer (MBC) has changed markedly over recent years with the emergence of new ETs and the use of molecularly targeted agents. Cytotoxic chemotherapy continues, however, to have an important role in these patients and it is important to maximize its efficacy while minimizing toxicity to optimize outcomes. This review examines current HR-positive/HER2-negative MBC clinical guidelines and addresses key questions around the use of chemotherapy in the face of emerging therapeutic options. Specifically, the indications for chemotherapy in patients with HR-positive/HER2-negative MBC and the choice of optimal chemotherapy are discussed.

Effectiveness and safety of eribulin for human epidermal growth factor receptor 2 negative metastatic breast cancer in a real-world population

BACKGROUND

Eribulin's clinical benefit remains unclear; so, studies analyzing its effectiveness in routine clinical practice are interesting.

PATIENTS AND METHODS

This is a multicenter, retrospective study including patients with human epidermal growth factor receptor-2-negative metastatic breast cancer which assesses effectiveness and safety of eribulin.

RESULTS

A total of 140 women were included, with a median age of 57 years. The median overall survival and progression-free survival were 8.8 (95% confidence interval: 6.1-11.4) and 2.8 months (95% confidence interval: 2.5-3.1), respectively. For patients with hormonal receptor expression, a significantly longer progression-free survival was observed: 3.4 (95%confidence interval: 2.3-4.5) versus triple negative: 2.0 (95%confidence interval: 1.7-2.3) months, p = 0.003. Also, those who had received capecitabine prior to eribulin had a higher median overall survival than those who had not received it (9.5 months, 95% confidence interval: 6.6-12.5 vs. 4.8 months, 95% confidence interval: 3.4-6.2; p = 0.001). When only triple-negative patients were included, median overall survival was 6.5 (95% confidence interval: 0.1-16.2) for those who had received previous capecitabine versus 4.3 (95% confidence interval: 2.8-5.8) months for patients who had not received it; p =0.006. The safety profile of eribulin was adequate.

CONCLUSION

Effectiveness of eribulin in a real-life human epidermal growth factor receptor-2--negative population is lower than that observed in clinical trials. Its benefit seems to be higher in patients with hormonal receptor expression and patients who had received capecitabine prior to eribulin. The safety profile of eribulin is adequate.

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.

Antibody-drug conjugate MORAb-202 exhibits long-lasting antitumor efficacy in TNBC PDx models

The antibody‐drug conjugate (ADC) MORAb‐202, consisting of farletuzumab paired with a cathepsin B–cleavable linker and eribulin, targets folate receptor alpha (FRA), which is frequently overexpressed in various tumor types. MORAb‐202 was highly cytotoxic to FRA‐positive cells in vitro, with limited off‐target killing of FRA‐negative cells. Furthermore, MORAb‐202 showed a clear in vitro bystander cytotoxic effect in coculture with FRA‐positive/negative cells. In vivo antitumor efficacy studies of MORAb‐202 were conducted with a single administration of MORAb‐202 in triple‐negative breast cancer (TNBC) patient–derived xenograft (PDx) models expressing low and high levels of FRA. MORAb‐202 exhibited durable efficacy proportional to tumor FRA expression. Toxicology studies (Q3Wx2) in nonhuman primates suggested that the major observed toxicity of MORAb‐202 is hematologic toxicity. Overall, these findings support the concept that MORAb‐202 represents a promising investigational ADC for the treatment of TNBC patients.

Sacituzumab Govitecan in Metastatic Triple-Negative Breast Cancer

BACKGROUND

Patients with metastatic triple-negative breast cancer have a poor prognosis. Sacituzumab govitecan is an antibody-drug conjugate composed of an antibody targeting the human trophoblast cell-surface antigen 2 (Trop-2), which is expressed in the majority of breast cancers, coupled to SN-38 (topoisomerase I inhibitor) through a proprietary hydrolyzable linker.

METHODS

In this randomized, phase 3 trial, we evaluated sacituzumab govitecan as compared with single-agent chemotherapy of the physician's choice (eribulin, vinorelbine, capecitabine, or gemcitabine) in patients with relapsed or refractory metastatic triple-negative breast cancer. The primary end point was progression-free survival (as determined by blinded independent central review) among patients without brain metastases.

RESULTS

A total of 468 patients without brain metastases were randomly assigned to receive sacituzumab govitecan (235 patients) or chemotherapy (233 patients). The median age was 54 years; all the patients had previous use of taxanes. The median progression-free survival was 5.6 months (95% confidence interval [CI], 4.3 to 6.3; 166 events) with sacituzumab govitecan and 1.7 months (95% CI, 1.5 to 2.6; 150 events) with chemotherapy (hazard ratio for disease progression or death, 0.41; 95% CI, 0.32 to 0.52; P<0.001). The median overall survival was 12.1 months (95% CI, 10.7 to 14.0) with sacituzumab govitecan and 6.7 months (95% CI, 5.8 to 7.7) with chemotherapy (hazard ratio for death, 0.48; 95% CI, 0.38 to 0.59; P<0.001). The percentage of patients with an objective response was 35% with sacituzumab govitecan and 5% with chemotherapy. The incidences of key treatment-related adverse events of grade 3 or higher were neutropenia (51% with sacituzumab govitecan and 33% with chemotherapy), leukopenia (10% and 5%), diarrhea (10% and <1%), anemia (8% and 5%), and febrile neutropenia (6% and 2%). There were three deaths owing to adverse events in each group; no deaths were considered to be related to sacituzumab govitecan treatment.

CONCLUSIONS

Progression-free and overall survival were significantly longer with sacituzumab govitecan than with single-agent chemotherapy among patients with metastatic triple-negative breast cancer. Myelosuppression and diarrhea were more frequent with sacituzumab govitecan. (Funded by Immunomedics; ASCENT ClinicalTrials.gov number, NCT02574455; EudraCT number, 2017-003019-21.).

Emerging drugs for the treatment of triple-negative breast cancer: a focus on phase II immunotherapy trials

Introduction: Triple-negative breast cancer accounts for 10-20% of invasive breast cancers and is characterized by an aggressive phenotype and poor outcomes in the early and advanced settings compared to other breast cancer subtypes. Chemotherapy continues to be the mainstay of treatment, but recent advances have demonstrated the benefit of adding immune checkpoint inhibitors (ICIs) to chemotherapy regimens for patients with both early and advanced TNBC, particularly if PD-L1-positive. Despite these results, further improvements are needed.Areas covered: This review covers immunotherapy drugs which have recently completed, involved in ongoing or due to start phase II trials. This includes approaches to augment the response to existing ICIs, next-generation ICIs, combination treatments with targeted agents and drugs that target the tumor microenvironment. Potential development issues are also discussed.Expert opinion: The field of immunotherapy is developing rapidly and holds great promise for patients with TNBC. Promising avenues of research currently in phase II trials include targeting multiple immune checkpoints simultaneously and the addition of phosphatidylinositol 3-kinase (PI3K)/AKT inhibitors to ICI/chemotherapy regimens. A better understanding of the immunosuppressive role played by the tumor microenvironment has also been important. However, challenges remain, particularly regarding the need for more effective predictive biomarkers.

Incorporation of eribulin in the systemic treatment of metastatic breast cancer patients in Australia

PURPOSE

Review of utilization and efficacy of eribulin in Australian metastatic breast cancer (MBC) patients.

METHODS

Retrospective review of consecutive MBC patients treated with eribulin in tertiary Australian BC centers. Key inclusion criteria included eribulin administration in nonclinical trial setting from October 2014 onwards, known duration of MBC systemic treatments administered and known follow-up date after eribulin. Cox regression model was used to assess survival.

RESULTS

Study population comprised 266 patients from eight centers treated between October 2014 and May 2018. Median age at time of MBC diagnosis was 54 years with 18% of patients having de novo MBC. Seventy-six percent had hormone receptor positive (HRp) disease, 19% triple negative (TN) and 5% HER2-positive. CNS involvement was present in 36% of patients. Eribulin was most frequently given as third-line chemotherapy (36%), with no prior anthracycline exposure in 14% of total population. Eribulin was given more frequently as ≤third-line chemotherapy than > third-line in patients with TN disease, ≥ two metastatic sites or CNS disease. Median overall survival (OS) from eribulin administration was 9.2 (95% CI [8.0, 10.3]) months.

CONCLUSION

Similar efficacy was demonstrated for eribulin when given in the first-line to beyond the fifth line of chemotherapy in all subtypes of MBC.

Second-line Eribulin in Triple Negative Metastatic Breast Cancer patients. Multicentre Retrospective Study: The TETRIS Trial

Introduction: Large and consistent evidence supports the use of eribulin mesylate in clinical practice in third or later line treatment of metastatic triple negative breast cancer (mTNBC). Conversely, there is paucity of data on eribulin efficacy in second line treatment. Methods: We investigated outcomes of 44 mTNBC patients treated from 2013 through 2019 with second line eribulin mesylate in a multicentre retrospective study involving 14 Italian oncologic centres. Results: Median age was 51 years, with 11.4% of these patients being metastatic at diagnosis. Median overall survival (OS) and progression free survival (PFS) from eribulin starting were 11.9 (95%CI: 8.4-15.5) and 3.5 months (95%CI: 1.7-5.3), respectively. We observed 8 (18.2%) partial responses and 10 (22.7%) patients had stable disease as best response. A longer PFS on previous first line treatment predicted a better OS (HR=0.87, 95%CI: 0.77-0.99, p= 0.038) and a longer PFS on eribulin treatment (HR=0.92, 95%CI: 0.85-0.98, p=0.018). Progression free survival to eribulin was also favorably influenced by prior adjuvant chemotherapy (HR=0.44, 95%CI: 0.22-0.88, p=0.02). Eribulin was generally well tolerated, with grade 3-4 adverse events being recorded in 15.9% of patients. Conclusions: The outcomes described for our cohort are consistent with those reported in the pivotal Study301 and subsequent observational studies. Further data from adequately-sized, ad hoc trials on eribulin use in second line for mTNBC are warranted to confirm our findings.

Eribulin Efficacy on Brain Metastases in Heavily Pretreated Patients with Metastatic Breast Cancer

The onset of brain metastases (BM) is a major turning point during advanced breast cancer (ABC) evolution, with only few treatment options when local therapies have failed. The therapeutic effect of eribulin, a wildly used drug in the treatment of ABC, remains unclear in this setting. Patients and Methods: We performed a retrospective observational study to assess eribulin efficacy in patients with ABC who displayed BM at time of eribulin initiation. We collected data from the medical files of all ABC patients who received eribulin at our institution from 2012 until 2020. Our main endpoint was the central nervous system (CNS) progression-free survival. (CNS-PFS). Other evaluation criteria were extra-cranial progression free survival (PFS) and overall survival (OS). Results: Twenty patients with BM monitoring data available were selected out of the 549 who received eribulin during the inclusion period. Fifteen patients (75%) had BM progressive as the best response, three patients (15%) had disease stabilization for more than 6 months and only one patient had a partial response according to RECIST 1.1 criteria. Median CNS-PFS was 3.39 months (95CI (3.02–3.76)). Cox univariate analysis identified molecular subtype as the only prognostic parameter in our cohort, with patients with hormone-receptor positive tumors less likely to experience CNS progression than those with triple-negative MBC (HR = 0.23 (95CI = 0.07–0.80), p = 0.021). Median extra-cranial PFS was 2.67 months (95CI (2.33–3.01)). Median OS was 7.68 months (95CI (0–17.41)). Conclusion: Eribulin seems to have only a limited impact on BM evolution. Hormone receptors expression may identify a subset of patients with better BM control.

Clinical Utility of Eribulin Mesylate in the Treatment of Breast Cancer: A Chinese Perspective

Eribulin mesylate, a synthetic derivative of the anti-mitotic agent halichondrin B, has a unique tubulin-based mechanism of action that is distinct from other anti-microtubule agents including taxanes and vinca alkaloids. Consistent with this unique activity, eribulin has shown clinical efficacy in patients with metastatic breast cancer (MBC) that progressed following prior taxane and anthracycline therapy. The evidence presented in this review indicates that eribulin represents a treatment option for patients with HER2-negative metastatic breast cancer. Improved survival outcomes and better tolerability compared with vinorelbine supported the first approval of eribulin in China in 2019; eribulin was approved for women with locally advanced/metastatic HER2-negative breast cancer after treatment failure with at least two chemotherapy regimens, including an anthracycline and a taxane. Eribulin has also shown promising efficacy in patients with HER2-positive advanced breast cancer when used in combination with trastuzumab or pertuzumab, and subgroup analyses from the Phase III clinical trials support the continued evaluation of eribulin in patients with triple-negative disease. The unique non-mitotic effects of eribulin, including vascular remodeling, coupled with its clinical efficacy and safety profile, may permit the broader use of this agent in patients with MBC.

Eribulin Mesylate for the Treatment of Metastatic Hormone-refractory and Triple-negative Breast Cancer: A Multi-institutional Real-world Report on Efficacy and Safety

OBJECTIVE

Eribulin mesylate (EM) is a fully synthetic macrocyclic ketone analogue of the marine natural product halichondrin. EM has been reported to be active in metastatic breast cancer. In this paper, we report efficacy and safety of data of EM in a retrospective, real-world series of patients with poor prognosis, hormone-refractory, or triple-negative metastatic breast cancer.

MATERIALS AND METHODS

The analysis was carried out at 4 interrelated oncology centers. EM was delivered at the dose of 1.4 mg/m2 in 100 mL of normal saline over 2 to 5 minutes on days 1 and 8 every 21 days. EM was continued until disease progression or unacceptable toxicity. Side effects were reported every cycle as per standard clinical practice and graded according to NCI-CTCAE, version 4.0. Time-to-progression and overall survival were reported.

RESULTS

In this series of 90 patients the overall response rate was 22%, and 21% and 23% in the hormonal-resistant group and the triple-negative one, respectively. Stable disease was recorded in 24%, 21%, and 27%, respectively, in the whole series, the hormonal-resistant group, and the triple-negative one, respectively. Time-to-progression was 3.5 months (range, 1 to 22 mo) in the whole series and 3.0 months (range, 1 to 14.7 mo) and 3.4 months (range, 2.2 to 16.2 mo) in the hormonal-resistant group and the triple-negative one, respectively. Overall survival reached a median of 11.4 months.

CONCLUSIONS

This multicenter study, albeit retrospective, demonstrates the activity of this combination as third-line chemotherapy option in a challenging clinical setting such as triple-negative or hormone-resistant patients with breast cancer progressing after several lines of hormonal manipulations.

A transposon screen identifies enhancement of NF-κB pathway as a mechanism of resistance to eribulin

BACKGROUND

Eribulin mesylate (eribulin) is an efficient microtubule inhibitor that is used for metastatic breast cancer. However, breast cancer can develop resistance to eribulin. This resistance mechanism needs to be elucidated.

METHODS

A transposon mutagenesis screen was conducted using a pPB-SB-CMV-puro-SD plasmid and pCMV-PBase transposase. Viability and cytotoxicity were analyzed by MTT assay and flow cytometry, respectively. Real-time PCR and western blot were used for gene expression analysis. In addition, vivo study was also designed to analyze therapy efficiency.

RESULTS

TAB2, which is part of the nuclear factor-kappa B (NF-κB) pathway, was identified as a candidate eribulin-resistant gene. TAB2 down-regulation resulted in significantly lower cell viability and higher cytotoxicity of cells treated with eribulin, while TAB2 up-regulation showed opposite results. Similarly, combination of NF-κB inhibitors [Bay-117082 and QNZ (quinazoline derivative)] with eribulin showed significantly lower cell viability and higher drug cytotoxicity than single agent treatment with eribulin in MDA-MB-231 cells. However, QNZ increased NF-κB activity in MCF7 cells by up-regulating TAB2, which reduced the sensitivity to eribulin. Furthermore, combination of Bay-117082 with eribulin induced greater regression of MDA-MB-231 tumors compared to eribulin monotherapy in vivo.

CONCLUSIONS

These results consistently illustrated that TAB2-NF-κB pathway may increases resistance to eribulin in breast cancer models. Moreover, these results support the use of a combination strategy of eribulin with NF-κB inhibitors, and provide evidence that transposon mutagenesis screens are capable of identifying drug-resistant genes.

Phase II study of eribulin in combination with gemcitabine for the treatment of patients with locally advanced or metastatic triple negative breast cancer (ERIGE trial). Clinical and pharmacogenetic results on behalf of the Gruppo Oncologico Italiano di Ricerca Clinica (GOIRC)

Background

The combination of a microtubule inhibitor (eribulin) with a nucleoside analog (gemcitabine) may synergistically induce tumor cell death, particularly in triple negative breast cancer (TNBC) characterized by high cell proliferation, aggressive behavior, and chemo-resistance.

Patients and methods

This is an open-label, multicenter phase II study evaluating the combination of eribulin (0.88 mg/m²) plus gemcitabine (1000 mg/m²) on days 1 and 8 of a 21-day cycle as either first- or second-line treatment of locally advanced or metastatic TNBC. The primary endpoint was the objective response for evaluable patients. A prospective, molecular correlative study was carried out to assess the role of germinal BRCA pathogenic variants and single nucleotide polymorphisms (SNPs) in predicting efficacy and toxicity of the combination regimen.

Results

From July 2013 to September 2016, 83 evaluable patients were enrolled. They received a median number of six cycles of treatment. An overall response rate (ORR) of 37.3% (31 patients) was observed, with a complete response rate of 2.4% and a partial response rate of 34.9%; the clinical benefit rate was 48.8%. With a median follow-up of 28.8 months, the median response duration was 6.6 months, the median progression-free survival (PFS) was 5.1 months, and the median overall survival (OS) was 14.5 months. The most common grade 3-4 adverse events were aminotransferase elevation (in 25% of the patients) and neutropenia (in 23.8%). Women with BRCA1/2 pathogenic variants were associated with worse ORR, PFS, and OS than BRCA1/2 wild-type carriers. CYP3A4 and FGD4 SNPs were associated with increased risk of liver toxicity. Three different SNPs in CDA∗2, RRM1, and CYP2C8 genes were significantly associated with poorer OS.

Conclusions

The combination of eribulin and gemcitabine showed promising activity and a moderate toxicity profile in metastatic TNBC. BRCA status and pharmacogenetics tests may help identify patients with high probability of response with negligible toxicity.

EudraCT number

2012-003505-10.

•

Eribulin plus gemcitabine showed a remarkable best ORR of 37.3% and a clinical benefit rate of 48.8%.

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The most common grade 3/4 toxicities were liver toxicity and neutropenia without febrile neutropenia.

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The study regimen partially lost its efficacy in patients harboring BRCA1/2 pathogenic variants.

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SNPs in CYP3A4 and FGD4 genes were associated with increased risk of liver toxicity.

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Three different SNPs in CDA∗2, RRM1, and CYP2C8 genes were significantly associated with poorer OS.

Antibody-drug conjugates in metastatic triple negative breast cancer: a spotlight on sacituzumab govitecan, ladiratuzumab vedotin, and trastuzumab deruxtecan

INTRODUCTION

Metastatic triple-negative breast cancers (mTNBC) are characterized by aggressive behavior and worse clinical outcomes than other breast cancer subtypes, as well as poor response to cytotoxic chemotherapies. The use of antibody-drug conjugates (ADCs) has been investigated as a potential treatment strategy, particularly in heavily pretreated disease.

AREAS COVERED

This article reviews the preclinical and clinical data supporting the use of the ADCs sacituzumab govitecan (SG), ladiratuzumab vedotin (LV), and trastuzumab deruxtecan (T-DXd) in mTNBC, and highlights ongoing clinical trials and future clinical applications.

EXPERT OPINION

SG, LV, and T-DXd have demonstrated their potential to meaningfully improve clinical outcomes in patients with pretreated mTNBC, as demonstrated by notable response rates in phase I/II and, for SG, phase III clinical trials. Investigation of their use in combination with other agents, including PARP inhibitors and checkpoint inhibitors, is ongoing in the metastatic setting, and their application in early-stage TNBCs are under investigation. ADCs are therefore expected to redefine treatment paradigms in TNBC.

Systematic review of Real-World effectiveness of eribulin for locally advanced or metastatic breast cancer

BACKGROUND

Eribulin mesylate (eribulin) is indicated for patients with metastatic breast cancer (MBC) who have previously received at least two chemotherapies in the US and for patients with locally advanced breast cancer (LABC) or MBC who have progressed after at least one chemotherapy in the European Union (EU). In both indications, prior therapy should include an anthracycline and a taxane in adjuvant or metastatic setting. Numerous studies evaluated eribulin in real-world (RW) breast cancer populations to reinforce its consistent effectiveness beyond registration randomized controlled trials (RCTs) that reported median overall survival (OS) of 13.1 and 15.9 months. In this systematic literature review (SLR), we summarize the cumulative evidence on eribulin's RW effectiveness in LABC/MBC.

METHODS

We searched through Medline/PubMed and Embase databases between 2012 and 2019 for articles reporting RW eribulin use in the second- or third-line or later LABC/MBC setting. Because eribulin showed greatest OS benefits in triple negative breast cancer (TNBC) in RCTs, we also reviewed this tumor subtype. OS and progression-free survival (PFS) were the effectiveness outcomes of interest.

RESULTS

Overall, 34 journal articles or abstracts met the selection criteria. Median OS ranged between 6.9 and 28.0 months; median PFS varied from 2.3 to 14.7 months. Eight studies reported OS outcomes for TNBC patients, and median OS ranged between 3.0 and 23.0 months.

CONCLUSION

The SLR showed high variability in OS and to a lesser extent in PFS associated with eribulin use in RW setting. Despite heterogeneity in line of use and patient subtypes, this SLR supports effectiveness of eribulin for LABC/MBC in clinical practice.

Measuring Tumor Epichaperome Expression Using [124I] PU-H71 Positron Emission Tomography as a Biomarker of Response for PU-H71 Plus Nab-Paclitaxel in HER2-Negative Metastatic Breast Cancer

PURPOSE

Epichaperome network maintenance is vital to survival of tumors that express it. PU-H71 is an epichaperome inhibitor that binds to the ATP-binding site of HSP90 and has demonstrated antitumor activity in breast cancer xenograft models and clinical safety in patients. PU-positron emission tomography (PET) is a theragnostic imaging tool that allows visualization of the epichaperome target. In this phase Ib trial, we present safety and tolerability for PU-H71 plus nab-paclitaxel in HER2-negative patients with metastatic breast cancer (MBC) and the utility of PU-PET as a noninvasive predictive biomarker.

METHODS

We performed a 3 + 3 dose-escalation study with escalating PU-H71 doses and standard nab-paclitaxel. The primary objective was to establish safety and determine maximum tolerated dose (MTD)/recommended phase 2 dose. Secondary objectives were to assess pharmacokinetics and clinical efficacy. Patients could enroll in a companion PU-PET protocol to measure epichaperome expression before treatment initiation to allow exploratory correlation with treatment benefit.

RESULTS

Of the 12 patients enrolled, dose-limiting toxicity occurred in one patient (G3 neutropenic fever) at dose level 1; MTD of PU-H71 was 300 mg/m² plus nab-paclitaxel 260 mg/m² administered every 3 weeks. Common toxicities included diarrhea, fatigue, peripheral neuropathy, and nausea. PU-H71 systemic exposure was not altered by nab-paclitaxel administration. Two of 12 patients had partial response (overall response rate, 17%) and the clinical benefit rate was 42% (5 of 12). Time to progression was associated with baseline epichaperome positivity and PU-H71 peak standard uptake value (SUV), with more durable disease control observed with high epichaperome levels.

CONCLUSION

The combination of PU-H71 and nab-paclitaxel was well tolerated, with evidence of clinical activity. More durable disease control without progression was observed in patients with high baseline epichaperome expression. A phase II trial of this combination with PU-PET as a companion diagnostic for patient selection is currently planned.

Progress: Targeted Therapy, Immunotherapy, and New Chemotherapy Strategies in Advanced Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is one of the most aggressive subtypes of breast cancer, accounting for approximately 15% of cases, and is defined by the lack of expression of hormone receptors (estrogen and progesterone receptors) and lack of amplification or overexpression of human epidermal growth receptor 2 (HER2). Due to the lack of targets of hormone receptors and HER2, treatment of TNBC or advanced TNBC relies on conventional chemotherapeutic agents, but their efficacy and prognosis are poor. In patients with advanced TNBC, poorer outcomes are observed. Recently, with the launch of clinical trials and advancements in molecular studies, targeted therapy for signaling transduction pathways, immunotherapy for immune checkpoints, and new chemotherapy strategies have provided feasible or potential therapeutic options for advanced TNBC. This review aimed to summarize recent progress in targeted therapy, immunotherapy, and chemotherapy for advanced TNBC.

Overall survival analysis in patients with metastatic breast cancer and liver or lung metastases treated with eribulin, gemcitabine, or capecitabine

Purpose

The purpose of this study was to estimate the overall survival (OS) in real-world clinical practice in patients with metastatic breast cancer (MBC) and visceral metastases (liver or lung) treated in the third-line setting with eribulin, gemcitabine or capecitabine overall and in the major clinical categories of MBC (TNBC, HR+/HER2−, and HER2+).

Methods

A retrospective, observational study was conducted with de-identified patient electronic health records from the Cancer Treatment Centers of America (CTCA). Patients with a diagnosis of metastatic breast with lung or liver metastases, and treated with eribulin, gemcitabine, or capecitabine as third-line therapy were included in the analysis. Landmark survival was calculated as percentage of patients alive at 6, 12, 24, and 36 months. Overall survival was compared between treatment arms within TNBC and HR+/HER2− using log-rank analysis. Cox regression analyses was performed to estimate hazard ratios for comparison of treatments within TNBC and HR+/HER2− subtype.

Results

443 patients with liver or lung metastases received third-line therapy with eribulin (n = 229), gemcitabine (n = 134), or capecitabine (n = 80). Eribulin patients had a higher percentage of patients alive at all landmark timepoints vs. gemcitabine, and a higher percentage of patients alive until 36 months vs. capecitabine. Median survival times showed that overall, and within the TNBC and HR+/HER2− subtype, patients receiving eribulin had a numerically higher median overall survival.

Conclusions

This real-world evidence study is consistent with randomized clinical trial data and demonstrates consistency of eribulin effectiveness in MBC patients with lung or liver metastases overall and in TNBC and HR+/HER2− disease.

Utility of the Absolute Lymphocyte Count and Neutrophil/Lymphocyte Ratio for Predicting Survival in Patients with Metastatic Breast Cancer on Eribulin: A Real-World Observational Study

INTRODUCTION

Previous studies have suggested that the efficacy of eribulin is influenced by the activity of antitumor immunity of patients. Absolute lymphocyte count (ALC) and the neutrophil/lymphocyte ratio (NLR) are easily available parameters associated with the immunological status of patients.

OBJECTIVE

Here we tried to classify patients' immunological status by using the scatter plot of ALC and NLR, and investigated its utility for predicting survival among patients with metastatic breast cancer receiving eribulin.

METHODS

The medical records of 125 patients who received eribulin for metastatic breast cancer at our hospital between July 2011 and April 2019 were retrospectively reviewed. Uni- and multivariate analyses were performed to determine the association between baseline ALC/NLR and progression-free survival (PFS)/overall survival (OS). The cutoff values for ALC and NLR were determined using scatter plot analysis.

RESULTS

The entire cohort was classified into immunologically favorable (ALC ≥1,500/µL, 30 patients), intermediate (ALC <1,500/µL, NLR <5.0, 76 patients), and unfavorable (NLR ≥5.0, 19 patients) groups. Univariate analysis showed significant differences in PFS and OS between the groups, whereas multivariate analysis revealed that ALC ≥1,500/µL and NLR ≥5.0 were independent predictors of PFS, with adjusted hazard ratios (95% CI) of 0.57 (0.33-0.99) and 1.78 (1.00-3.15), respectively. NLR ≥5.0 was also associated with worse OS (adjusted hazard ratio: 0.55; 95% CI 0.35-0.88; p = 0.013).

CONCLUSIONS

Among patients with metastatic breast cancer receiving eribulin, survival outcomes were well stratified according to baseline peripheral blood ALC and NLR. Accordingly, high ALC and NLR can be used as predictive markers for longer disease control and worse survival, respectively.

53BP1 Accumulation in Circulating Tumor Cells Identifies Chemotherapy-Responsive Metastatic Breast Cancer Patients

Evidence suggests that the DNA end-binding protein p53-binding protein 1 (53BP1) is down-regulated in subsets of breast cancer. Circulating tumor cells (CTCs) provide accessible “biopsy material” to track cell traits and functions and their alterations during treatment. Here, we prospectively monitored the 53BP1 status in CTCs from 67 metastatic breast cancer (MBC) patients with HER2- CTCs and known hormone receptor (HR) status of the primary tumor and/or metastases before, during, and at the end of chemotherapeutic treatment with Eribulin. Nuclear 53BP1 staining and genomic integrity were evaluated by immunocytochemical and whole-genome-amplification-based polymerase chain reaction (PCR) analysis, respectively. Comparative analysis of CTCs from patients with triple-negative and HR+ tumors revealed elevated 53BP1 levels in CTCs from patients with HR+ metastases, particularly following chemotherapeutic treatment. Differences in nuclear 53BP1 signals did not correlate with genomic integrity in CTCs at baseline or with nuclear γH2AX signals in MBC cell lines, indicating that 53BP1 detected features beyond DNA damage. Kaplan–Meier analysis revealed an increasing association between nuclear 53BP1-positivity and progression-free survival (PFS) during chemotherapy until the final visit. Our data suggest that 53BP1 detection in CTCs could be a useful marker to capture dynamic changes of chemotherapeutic responsiveness in triple-negative and HR+ MBC.

Use of eribulin as an earlier-line chemotherapy for patients with HER2-negative metastatic breast cancer

Background: Previous prospective studies have shown that eribulin improves the survival in patients with metastatic breast cancer (MBC). However, the optimal timing of its administration to achieve the longest extended survival and the efficacy of using eribulin monotherapy as earlier-line chemotherapy are yet unclear. Methods: We identified all consecutive female patients with MBC who received any chemotherapeutic intervention for metastatic disease at our institution between July 2012 and December 2017, excluding patients with HER2-positive disease. Those who received eribulin monotherapy for MBC were classified under the eribulin cohort, whereas those who never received eribulin were included in the non-eribulin (Non-E) cohort. Among the patients in the eribulin cohort, those who received eribulin as the first- or second-line chemotherapy for MBC were further classified under the earlier-line eribulin (EE), and otherwise classified under the later-line eribulin (LE) cohorts. The survival of patients was assessed using the log-rank test. A multivariable Cox proportional hazards model was used to assess the independent efficacy and timing of eribulin monotherapy. The inverse probability of treatment weighting (IPTW) estimate was utilized to compare the EE and LE cohorts. Results: Of the 507 patients who were initially screened, 226 were included after an intensive chart review: 93, 49, and 84 patients were included in the Non-E, EE, and LE cohorts, respectively. The eribulin cohort showed significantly longer overall survival than the Non-E cohort (30.3 vs. 22.2 months, p = 0.0217). No significant difference was observed in the progression-free survival of the EE and LE cohorts (3.4 vs. 4.4 months, p = 0.1337) after adjusting for clinically relevant factors using IPTW estimates. LE cohort showed good overall survival (OS) compared with patient group of Non-E and EE by log-rank testing (p = 0.0398), although multivariate analysis did not demonstrate eribulin administration timing as an independent prognostic factor of OS. OS was defined from the initiation of first-line chemotherapy date. Conclusions: Our data provided additional insights regarding the use of eribulin monotherapy as earlier-line chemotherapy. However, the optimal timing of eribulin monotherapy for MBC was not determined in the current study.

N-Cadherin mRNA Levels in Peripheral Blood Could Be a Potential Indicator of New Metastases in Breast Cancer: A Pilot Study

Background: There is growing evidence that patients with metastatic breast cancer whose disease progresses from a new metastasis (NM) have a worse prognosis than that of patients whose disease progresses from a pre-existing metastasis. The aim of this pilot study is to identify a blood biomarker predicting NM in breast cancer. Methods: The expression of epithelial (cytokeratin 18/19) or mesenchymal (plastin-3, vimentin, and N-cadherin) markers in the peripheral blood (PB) of recurrent breast cancer patients undergoing chemotherapy with eribulin or S-1 was measured over the course of treatment by RT-qPCR. The clinical significance of preoperative N-cadherin expression in the PB or tumor tissues of breast cancer patients undergoing curative surgery was assessed by RT-qPCR or using public datasets. Finally, N-cadherin expression in specific PB cell types was assessed by RT-qPCR. Results: The expression levels of the mesenchymal markers N-cadherin and vimentin were high in the NM cases, whereas that of the epithelial marker cytokeratin 18 was high in the pre-existing metastasis cases. High preoperative N-cadherin expression in PB or tumor tissues was significantly associated with poor recurrence-free survival. N-cadherin was expressed mainly in polymorphonuclear leukocytes in PB. Conclusion: N-cadherin mRNA levels in blood may serve as a novel prognostic biomarker predicting NM, including recurrence, in breast cancer patients.

Current treatment landscape for patients with locally recurrent inoperable or metastatic triple-negative breast cancer: a systematic literature review

Background

Metastatic triple-negative breast cancer (mTNBC), an aggressive histological subtype, has poor prognosis. Chemotherapy remains standard of care for mTNBC, although no agent has been specifically approved for this breast cancer subtype. Instead, chemotherapies approved for metastatic breast cancer (MBC) are used for mTNBC (National Comprehensive Cancer Network Guidelines [NCCN] v1.2019). Atezolizumab in combination with nab-paclitaxel was recently approved for programmed death-ligand 1 (PD-L1)–positive locally advanced or metastatic TNBC. Published historical data were reviewed to characterize the efficacy of NCCN-recommended (v1.2016) agents as first-line (1L) and second-line or later (2L+) treatment for patients with locally recurrent inoperable or metastatic TNBC (collectively termed mTNBC herein).

Methods

A systematic literature review was performed, examining clinical efficacy of therapies for mTNBC based on NCCN v1.2016 guideline recommendations. Data from 13 studies, either published retrospective mTNBC subgroup analyses based on phase III trials in MBC or phase II trials in mTNBC, were included.

Results

A meta-analysis of mTNBC subgroups from three phase III trials in 1L MBC reported pooled objective response rate (ORR) of 23%, median overall survival (OS) of 17.5 months, and median progression-free survival (PFS) of 5.4 months with single-agent chemotherapy. In two subgroup analyses from a phase III study and a phase II trial (n = 40 each), median duration of response (DOR) to 1L chemotherapy for mTNBC was 4.4–6.6 months; therefore, responses were not durable. A meta-analysis of seven cohorts showed the pooled ORR for 2L+ chemotherapy was 11% (95% CI, 9–14%). Median DOR to 2L+ chemotherapy in mTNBC was also limited (4.2–5.9 months) per two subgroup analyses from a phase III study. No combination chemotherapy regimens recommended by NCCN v1.2016 for treatment of MBC showed superior OS to single agents.

Conclusions

Chemotherapies have limited effectiveness and are associated with unfavorable toxicity profiles, highlighting a considerable unmet medical need for improved therapeutic options in mTNBC. In addition to the recently approved combination of atezolizumab and nab-paclitaxel for PD-L1–positive mTNBC, new treatments resulting in durable clinical responses, prolonged survival, and manageable safety profile would greatly benefit patients with mTNBC.

Impact of the number of prior chemotherapy regimens on outcomes for patients with metastatic breast cancer treated with eribulin: A post hoc pooled analysis

In a pivotal phase 3 study (Study 305), eribulin mesylate improved overall survival (OS) in patients with previously treated metastatic breast cancer (MBC) compared with treatment of physician's choice (TPC). This post hoc, pooled subgroup analysis of two phase 3 studies (Study 305 and Study 301) reports the influence of the number of prior chemotherapy regimens (0‐6) on OS in patients with locally advanced/MBC randomized to eribulin versus TPC/capecitabine. Patients with ≤ 3 prior chemotherapies for locally advanced/MBC had longer median OS with eribulin (15.3 months) versus control (13.2 months; hazard ratio, 0.858; P = .01).

Eribulin in Triple Negative Metastatic Breast Cancer: Critic Interpretation of Current Evidence and Projection for Future Scenarios

Triple negative breast cancer (TNBC) is characterized by distinctive biological features that confer an aggressive clinical behavior. In TNBC patients, the absence of well-defined driver pathways such as hormonal receptor expression or hyperactivation of the human epidermal growth factor receptor 2 (HER2) significantly reduce the spectrum of therapeutic options, which are currently mainly confined to chemotherapy. Thus far, median overall survival for patients with metastatic TNBC is about 9-12 months with conventional cytotoxic agents. However, the heterogeneity recently revealed at a gene expression level inside the TNBC family may help inform therapeutic decisions concerning the use of chemotherapy and hopefully lead the way to novel targeted options that include immunotherapy. Eribulin, a halichondrin class antineoplastic drug, is currently recommended for treatment of HER2 negative metastatic or recurrent breast cancer (BC) previously exposed to anthracyclines and taxanes, also for patients with a TNBC. It is currently indicated from the second line of treatment. In this review, we aim to analyze a wide range of cumulated evidence on eribulin use in TNBC including preclinical studies, intervention and observational clinical trials. Data from the real-world setting and the emerging evidence increasingly substantiating the rationale for combinations with new generation treatment strategies, e.g., PARP-inhibitors, immune checkpoint inhibitors, will be also discussed.

A population pharmacokinetic analysis of the oral CYP17 lyase and androgen receptor inhibitor seviteronel in patients with advanced/metastatic castration-resistant prostate cancer or breast cancer

PURPOSE

Seviteronel is an orally-administered selective cytochrome P450c17a 17,20-lyase and androgen receptor inhibitor with anti-tumor activity in vitro and in vivo, and clinical activity in men with advanced castration-resistant prostate cancer (CRPC) and men and women with advanced breast cancer. The purpose of this study was to assess the pharmacokinetics (PK) of seviteronel across the aforementioned populations.

METHODS

This report describes the PK of seviteronel (50-750 mg, QD or BID) using noncompartmental and population approaches from 243 patients with advanced breast or prostate cancer pooled across 4 clinical studies. First dose and steady-state PK were examined, as well as covariates including prandial status, sex and concomitant dexamethasone.

RESULTS

Seviteronel PK can be characterized by transit absorption and a bi-phasic first-order elimination while accounting for covariance between random effects. Prandial status did not significantly affect any parameters to a clinically-relevant extent. Both sex and body weight were significant covariates on clearance, explaining 37% of the interindividual variability on that parameter. There were no significant effects from the race or the presence of a corticosteroid (either dexamethasone or prednisone).

CONCLUSIONS

Seviteronel demonstrates linear PK over the dose range of 50-750 mg given either BID or QD in men with advanced CRPC or men and women with breast cancer. The disposition of seviteronel following oral administration is well described by this population PK model and can be used for accurate simulations for future studies with body weight and sex affecting clearance, but not to a clinically-meaningful degree requiring a change in the current dosing scheme.

Gene Alterations in Triple-Negative Breast Cancer Patients in a Phase I/II Study of Eribulin and Olaparib Combination Therapy

BACKGROUND

We conducted a phase I/II clinical trial to evaluate the efficacy of eribulin and olaparib in a tablet form (EO study) for triple-negative breast cancer (TNBC) patients. We hypothesized that somatic BRCA mutations and homologous recombination repair (HRR)-related gene alterations might affect efficacy.

METHODS

Our analyses identified mutations in HRR-related genes and BRCA1/2, and we subsequently evaluated their association to response by the EO study participants. Tissue specimens were obtained from primary or metastatic lesion. Tissue specimens were examined for gene mutations or protein expression using a Foundation Medicine gene panel and immunohistochemistry.

RESULTS

In the 32 tissue specimens collected, we detected 33 gene mutations, with the most frequent nonsynonymous mutations found in TP53. The objective response rates (ORRs) in patients with and without HRR-related gene mutation were 33.3% and 40%, respectively (P = .732), and the ORRs in patients with and without somatic BRCA mutations were 60% and 33.3%, respectively (P = .264), with the ORR numerically higher in the somatic BRCA-mutation group but not statistically significant. There was no correlation between immunohistochemistry status and response or between BRCA status or HRR-related gene mutation and survival. Immunohistochemical analysis indicated that EGFR-negative patients had a tendency for better progression-free survival (log-rank P = .059) and significantly better overall survival (log-rank P = .046); however, there was no correlation between the status of other immunohistochemistry markers and survival.

CONCLUSION

These findings suggested somatic BRCA mutation and EGFR-negativity as a potential biomarker for predicting the efficacy of eribulin/olaparib combination therapy. (UMIN000018721).

Real-life activity of eribulin mesylate among metastatic breast cancer patients in the multicenter national observational ESME program

Eribulin mesylate (EM) was recently approved for metastatic breast cancer (MBC) chemotherapy (CT) in late lines by the FDA, with debated results in second line. We evaluated outcomes in breast cancer patients receiving EM as second, third and fourth line in a national real-life cohort of 16,703 consecutive MBC patients initiating their first metastatic therapeutic line between 2008 and 2014. Primary and secondary objectives were overall survival (OS) and progression-free survival (PFS). An imbalance was seen for HER2+ tumors and concomitant anti-HER2 targeted therapies use, we thus performed a subanalysis in HER2- patients. PFS and OS were significantly better in EM patients in third and fourth lines, compared to "Other chemotherapies" patients (PFS: 4.14 vs. 3.02 months, p = 0.0010; 3.61 vs. 2.53 months, p = 0.0102, third and fourth-line; OS: 11.27 vs. 7.65 months, p = 0.0001; 10.91 vs. 5.95 months, p < 0.0001, third and fourth-line). No significant difference was reported in second-line (PFS: 5.06 vs. 4.14 months, p = 0.1171; OS: 13.99 vs. 11.66 months, p = 0.151). Among HER2- patients, a significant difference was seen for all lines, including 2nd-line (PFS: 4.57 vs. 3.91 months, p = 0.0379; OS: 14.98 vs. 10.51 months, p = 0.0113). In this large real-world database, HER2-negative MBC patients receiving EM in second or later CT line presented significantly better PFS and OS. This difference disappeared in second line in the overall population, probably because of the imbalance in HER2-targeted treatments use. Our results mirror those of the published randomized trials. The effect of anti-HER2 therapies addition in this setting still needs to be defined.

Quality of life outcomes including neuropathy-associated scale from a phase II, multicenter, randomized trial of eribulin plus gemcitabine versus paclitaxel plus gemcitabine as first-line chemotherapy for HER2-negative metastatic breast cancer: Korean Cancer Study Group Trial (KCSG BR13-11)

Background

A phase II clinical trial of the comparison between eribulin plus gemcitabine (EG) and paclitaxel plus gemcitabine (PG) as first-line chemotherapy for patients with metastatic breast cancer (MBC) found that the EG regimen was less neurotoxic, but was similar in efficacy to the PG regimen. In the present study, we analyzed functional assessment of cancer therapy-taxane (FACT-Taxane) questionnaires from patients in this clinical trial to determine their quality of life (QoL).

Methods

QoL was assessed using the Korean version of the FACT-Taxane questionnaires. After baseline assessment, QoL was assessed every 2 cycles for 12 cycles and every 3 cycles thereafter. The linear mixed model was used to evaluate the difference in QoL between the EG and PG arms.

Results

Of the 118 enrolled patients, 117 responded to the FACT-Taxane questionnaires at baseline, 1 in the PG arm did not. Baseline QoL scores were not different between the EG and PG arms. During treatment, taxane subscale scores were significantly higher in the PG arm than in the EG arm after 2–13 cycles of chemotherapy (all P < 0.05), except for the 11th cycle. Neuropathy-specific analysis showed that patients in the PG arm had earlier and more severe neuropathic symptoms than those in the EG arm (P < 0.001).

Conclusions

In our QoL analysis, the EG regimen delayed and decreased neuropathy as compared with the PG regimen. Therefore, eribulin would be a reasonable substitute for paclitaxel as first-line chemotherapy for MBC.

Electronic supplementary material

The online version of this article (10.1186/s40880-019-0375-7) contains supplementary material, which is available to authorized users.

The safety of eribulin for the treatment of metastatic breast cancer

Introduction: Eribulin mesylate is a highly potent anticancer agent approved for use in pretreated metastatic breast cancer (MBC). Clinical trials of eribulin in MBC have demonstrated activity against this tumor type, and a phase 3 study in patients with MBC previously treated with an anthracycline and a taxane showed a significant increase in overall survival (OS) with eribulin versus control regimens. Areas covered: This review presents overviews of the development of eribulin, its pharmacology, and its efficacy in MBC. A detailed review of its safety profile is presented, and the safety of eribulin is compared with other agents commonly used to treat MBC. Expert opinion: As eribulin is the only drug shown to improve OS in patients with pretreated MBC, it is an important treatment option for many patients. Eribulin is currently considered a second-line (Europe) or third-line (United States) therapy, and studies have been examining use in the first-line setting. The use of eribulin in combination with other therapies is beginning to be explored because its manageable safety profile makes it an ideal combination-treatment partner. Emerging eribulin combination-treatment data suggest a manageable toxicity profile, and eribulin is set to be a key drug for the treatment of MBC in the future.