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

A clinical systematic literature review of treatments among patients with advanced and/or metastatic human epidermal growth factor receptor 2 positive breast cancer

Aim: This systematic literature review aims to summarize the efficacy/effectiveness of treatments, including eribulin (ERI)-based and anti-human epidermal growth factor receptor 2 (HER2) treatments in advanced/metastatic HER2+ breast cancer. Methods: Three databases from 2016 to September 2021 were searched for clinical trials and observational studies in patients receiving first-line (1L) standard of care (SOC), second-line (2L) SOC or third-line or subsequent lines (3L+). Results: 2692 citations were screened, and 38 studies were included. Eleven studies were randomized-controlled trials (RCTs; 5 in 1L, 6 in 3L+), 6 were single-arm trials (5 in 1L, 1 in 3L+) and 21 were observational studies (13 in 1L, 6 in 2L, 4 in 3L+ [note that studies with subgroups for 1L, 2L, 3L+ are double-counted]). Longer overall survival (OS) was associated with 1L and 2L treatment, and for 3L+ studies that included ERI, ERI or trastuzumab (Tmab) + ERI led to longer OS than treatments of physician's choice (median OS of 11, 10 and 8.9 months, respectively). Progression-free survival was 9 months in Tmab + pertuzumab (Pmab) + ERI, 4 months in Tmab + ERI and 3.3 months in ERI. Conclusion: Available treatments provide a wide range of efficacy. However, later lines lack standardization and conclusions on comparative effectiveness are limited by differing trial designs. Thus, the chance of prolonged survival with new agents warrants further research.

Real-world treatment patterns and clinical outcomes in patients treated with eribulin after prior phosphoinositide 3-Kinase inhibitor treatment for metastatic breast cancer

PURPOSE

In 2010, the US Food and Drug Administration approved eribulin for the treatment of metastatic breast cancer (MBC). Since then, the treatment landscape has evolved with many new therapy classes, a more recent one being the small molecule inhibitors of phosphoinositide 3 kinase (PI3K). We sought to characterize the treatment patterns and clinical outcomes of patients with MBC who received eribulin following prior treatment with a PI3K inhibitor.

METHODS

A retrospective cohort study based on medical record review included MBC patients who initiated eribulin between March 2019 and September 2020 following prior treatment with a PI3K inhibitor was conducted. Patient demographics, treatment characteristics, and clinical outcomes were analyzed descriptively. Real-world progression-free survival (rwPFS) and overall survival (OS) were estimated from the initiation of eribulin therapy using Kaplan-Meier analyses.

RESULTS

82 eligible patients were included. Patients' median age at eribulin initiation was 62 years; 86.5% had hormone receptor-positive, human epidermal growth factor receptor 2-negative tumors. Eribulin was most often administered in the second or third line (82.9%) in the metastatic setting. Best overall response on eribulin was reported as complete or partial response in 72% of the patients. The median rwPFS was 18.9 months (95% confidence interval [CI], 12.4-not estimable); median OS was not reached. The estimated rwPFS and OS rates at 12 months were 63.3% (95% CI, 50.5-73.7) and 82.6% (95% CI, 72.4-89.3), respectively.

CONCLUSION

Our real-world study suggests that eribulin may be a potential treatment option for MBC patients who fail a prior PI3K inhibitor.

A unified strategy for the total syntheses of eribulin and a macrolactam analogue of halichondrin B

A unified synthetic route for the total syntheses of eribulin and a macrolactam analog of halichondrin B is described. The key to the success of the current synthetic approach includes the employment of our reverse approach for the construction of cyclic ether structural motifs and a modified intramolecular cyclization reaction between alkyl iodide and aldehyde functionalities to establish the all-carbon macrocyclic framework of eribulin. These syntheses, together with our previous work on the total syntheses of halichondrin B and norhalichondrin B, demonstrate and validate the powerful reverse approach in the construction of cyclic ether structural motifs. On the other hand, the unified synthetic strategy for the synthesis of the related macrolactam analog provides inspiration and opportunities in the halichondrin field and related polycyclic ether areas.

Comparative effectiveness and safety of eribulin in advanced or metastatic breast cancer: a systematic review and meta-analysis

Eribulin is one of the few recommended chemotherapies for locally advanced breast cancer (LABC) or metastatic breast cancer (MBC). We systematically searched MEDLINE Ovid, Cochrane Library, IPA, CINAHL, Web of Science and ProQuest Dissertations for studies evaluating eribulin versus non-eribulin regimens in LABC/MBC till January 15, 2021. Primary effectiveness and safety outcomes were overall survival (OS) and adverse events (AE), respectively. Hazard ratios (HR) and relative risks (RR) with 95 % confidence intervals (CIs) were calculated using fixed or random-effects meta-analyses. Of 1183 publications identified, 13 studies were included in this review. Eribulin based therapy showed significantly increased OS [HR (95 % CI) = 0.77 (0.67-0.88)] compared to non-eribulin in both main and sensitivity analyses, as well as subgroup analyses according to receptor expression and line of therapy. Incidence of all-grade neutropenia was the only significant AE in eribulin than non-eribulin groups. Eribulin has a manageable toxicity profile and provides significant survival benefit in LABC/MBC patients.

Effectiveness of Eribulin in Metastatic Breast Cancer: 10 Years of Real-World Clinical Experience in the United States

Introduction

Eribulin was approved in the United States (US) in 2010 for patients with metastatic breast cancer (MBC) who previously received at least two chemotherapeutic regimens, including anthracycline and taxane in the adjuvant or metastatic setting. With significant changes to the treatment landscape over the past decade, assessment of the real-world effectiveness of eribulin in clinical practice when used according to the approved US indication is valuable.

Methods

Patients with MBC were identified by community oncologists through a retrospective, multi-site patient chart review; de-identified data were abstracted into electronic case report forms. Eligible patients initiated eribulin consistent with approved US indication between 1 January 2011 and 31 December 2017. Clinical outcomes assessed included objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) in all patients and those with triple negative breast cancer (TNBC).

Results

The analysis included 513 patients (median 59.0 years; 38.8% with Eastern Cooperative Oncology Group status ≥ 2). Eribulin was third-line therapy for 78.0% of patients, and fourth-line or later for the remainder. ORR was 54.4%, median PFS was 6.1 months (95% CI: 5.8, 6.6), and median OS was 10.6 months (95% CI 9.9, 11.7) in all patients. Among the 49.9% of patients with TNBC, ORR was 55.1%, median PFS was 5.8 months (95% CI 5.1, 6.4), and median OS was 9.8 months (95% CI 8.6, 11.0).

Conclusion

The current retrospective chart review study reinforces the clinical effectiveness of eribulin in patients with MBC, including those with TNBC, when used according to the approved US indication in real-world clinical practice.