Clinical benefit of treatment with eribulin mesylate for metastatic triple‐negative breast cancer: Long‐term outcomes of patients treated in the US community oncology setting

Abstract

IntroductionReal‐world data are critical to demonstrate the consistency of evidence and external generalizability of randomized controlled trials (RCTs). This study examined characteristics and outcomes of metastatic triple‐negative breast cancer (mTNBC) patients treated with eribulin mesylate at community oncology practices in the United States.MethodsPhysicians identified mTNBC patients initiating eribulin between 1 January 2011 and 1 January 2014 and abstracted data into an electronic case report form (eCRF). Eribulin treatment in the metastatic setting was categorized as early use (EU, first‐/second‐line) and late use (LU, third‐line or later). Patient characteristics, overall survival (OS), disease response (per treating physician), and adverse events (AEs) rates in each group, respectively, are reported.ResultsOverall 252 eCRFs were completed: 125 (49.6%) EU and 127 (50.4%) LU. The median age at metastatic diagnosis was 53 years and 42.1% were stage IV at their initial diagnosis. The median duration of follow‐up from the initiation of first‐line treatment was 24 months. Rates of disease response (complete or partial per treating physician) were 69.9% in the EU group and 48.8% in the LU group. The five most commonly reported adverse events during eribulin were as follows: fatigue (65.1%), weakness (40.1%), decreased appetite (32.5%), neutropenia (31.0%), and leukopenia (27.4%). Discontinuation of eribulin due to AE was observed in 4.0% of patients. Median OS from initiation of eribulin was 23.0 months (95% CI: 18.7‐27.3) among EU and 14.7 (95% CI: 12.6‐16.9) among LU.ConclusionIn the real‐world eribulin‐treated mTNBC, patients have more sites of metastatic disease and exposure to greater numbers of prior therapies compared to RCTs. The median OS of 14.7 months among LU patients is consistent with, and slightly longer than the 13.1 months and 14.4 months reported in the EMBRACE and Study 301 clinical trials, respectively.

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

“…Toxicity was acceptable with no new safety issue. Median OS was 23 months in early lines and 14.7 months in later lines, the latter comparable to those of the EMBRACE and 301 trials 48. An Italian retrospective study on 44 heavily pretreated advanced BC patients showed longer PFS in ER-positive/HER2-negative tumors, and more favorable results have been observed in patients pretreated with first-line paclitaxel/bevacizumab in comparison to other first-line regimens.…”

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

“…Overall, eribulin treatment in our cohort was safe, with manageable toxicities. To our knowledge, evidence from literature concerning eribulin use in mTNBC as second-line treatment is lacking, with the majority of data being from retrospective studies [14][15][16][17][18][19]. In the pooled analysis of the EMBRACE trial and Study 301, the PFS on eribulin from TNBC patients was 2.8 months, but most of these patients had received more than 1 previous chemotherapy line [12].…”

The safety of eribulin for the treatment of metastatic breast cancer

“…Real-world reports have generally noted safety findings consistent with those found in clinical trials for eribulin. Across several studies in community settings in the United States, neutropenia (31% to 32.2%) and peripheral neuropathy (19.4% to 31.3%) were consistently reported as common AEs [52][53][54]. In a Belgian expanded-access program, the most frequent AEs with eribulin were fatigue/asthenia (all grades: 73.8%; grade 3/4: 9.2%), alopecia (all grades: 54.6%), peripheral neuropathy (all grades: 46.1%; grade 3/4: 7.1%), and neutropenia (all grades: 42.6%; grade 3/4: 36.9%) [55].…”