A global phase III study confirmed the effect of eribulin mesylate (ERI) as third- or later-line chemotherapy on overall survival (OS) for advanced or metastatic breast cancer. Meanwhile, in Japan, ERI can be used as first- or second-line. However, limited reports can be found on time to treatment failure (TTF) and/or OS for ERI as first- or second-line therapy comparing to late-line therapy in clinical practice.
We conducted a prospective study in patients with inoperable or recurrent HER2-negative breast cancer starting in September, 2014. We enrolled a similar number of patients receiving ERI as first- or second-line therapy and those receiving ERI as third- or later-line therapy, and with follow-up planned for up to two years (ClinicalTrials.gov: NCT02371174). The data collected by November 2017 was analyzed. TTF and OS were estimated using the Kaplan–Meier method. Multivariate Cox regression was used to identify the factors influencing TTF and OS.
We analyzed 634 patients. The mean age (± standard deviation) was 59.6 years (± 11.0), and 157 patients (24.8%) had triple-negative breast cancer. Of these patients, 319 received ERI as first- or second-line therapy and 315 as third- or later-line therapy. The median TTF (95% confidence interval [CI]) was 135 (121–164) and 119 (106–128) days, and the median OS (95% CI) was 555 (475–628) and 383 (342–459) days for first- or second-line- and third- or later-line therapy, respectively. A history of radiation therapy, complication of diabetes, liver metastasis, ECOG performance status, blood hemoglobin and aspartate aminotransferase levels at baseline, triple-negative breast cancer, and development of peripheral neuropathy after ERI treatment were significant factors influencing both TTF and OS.
Our real-world study showed patients with first- or second-line therapy of ERI have longer OS and TTF than those in third- or later-line therapy. These results suggested that patients with first- or second-line therapy of ERI have the potential for similar or more favorable outcomes from the ERI treatment compared with patients with third- or later-line therapy of ERI.
Clinical trial identification
NCT02371174, First release November 21, 2014.
Legal entity responsible for the study
Eisai Co., Ltd.
Eisai Co., Ltd.
M. Takahashi: Honorarium: Eisai, AstraZeneca, Pfizer. K. Inoue: Research funding (institutional): Eisai, Parexel, Puma Biotechnology, MSD, Novartis, GSK, Pfizer, Chugai Pharmaceutical, Daiichi Sankyo. Y. Sakata, H. Ikezawa, T. Matsuoka: Employee: Eisai Co. J. Tsurutani: Adviser: Eisai Co., Ltd. and Asahi Kasei Corporation; Honoraria: Eisai Co., Ltd., Taiho Pharmaceutical Co., Ltd., Roche Diagnostics K.K., Novartis Pharma, AstraZeneca K.K. All other authors have declared no conflicts of interest.