Eribulin Plus Gemcitabine (EG) vs Paclitaxel Plus Gemcitabine (PG) in HER2-Negative Metastatic Breast Cancer

Metastatic breast cancer (MBC) is an incurable disease and is needed to improve effective chemotherapy. Paclitaxel plus Gemcitabine (PG) combination chemotherapy is one of the preferred chemotherapeutic regimens for patients with MBC, and was found to be proper as a maintenance chemotherapy regimen with survival benefit and feasible toxicity profile as shown in a large phase III KCSG (Korean Cancer Study Group) study (Park Y et al. J Clin Oncol 31(14):1732, 2013). Eribulin mesylate is a microtubule-targeting agent that showed improved overall survival benefit as monotherapy for MBC patients as a new chemotherapeutic agent after failure of anthracycline and taxane in EMBRACE study (Cortes J et. al. Lancet 377:914-923, 2011). Eribulin was also reported its promising efficacy in another randomized phase III study that demonstrated eribulin as efficacious as capecitabine (Kaufman P et. al. Abstr# S6-6, SABCS 2012). Both study results showed potential clinical benefit in patients with triple negative MBC (TNBC). Thus, eribulin combined with gemcitabine may be a new potential regimen for early line therapy in patients with metastatic breast cancer. Furthermore, eribulin may have rational benefit compared with paclitaxel in terms of neurotoxicity. Although there is no direct evidence that eribulin has better neurotoxicity profile than taxane, eribulin tended to show less neurotoxicity compared with ixabepilone in a phase II trial (Vahdat, L et al. 2011 SABCS). Eribulin has no worsen toxicity as compared to paclitaxel. Therefore, EG may have less neurotoxicity comparing to PG. In phase I trial, eribulin in combination with gemcitabine was feasible in patients with advanced solid tumor treated with chemotherapy (\< 3 lines) (Goel R, et al, 2009 ASCO). Based on this rationale, the investigators are to conduct randomized phase II study comparing EG chemotherapy with PG chemotherapy for patients with HER-2 negative MBC as first-line chemotherapy. A total of 118 patients will be recruited. Patients will be randomized to a treatment arm by permutated method. The randomization ratio is 1:1. This study is multi-center, randomized, open label study.

Sex

All

Minimum age

19 Years

Inclusion Criteria:

1. Histologically confirmed metastatic, or recurrent breast cancer
2. HER2-negative breast cancer
3. age \> 18 years
4. ECOG performance status 0 - 2
5. Pre- or postmenopausal breast cancer patients with measurable or non-measurable lesions, who are candidates for chemotherapy
6. Life expectancy ≥ 3 months
7. No prior history of chemotherapy for metastatic, recurrent breast cancer
8. Patients may have received prior neoadjuvant or adjuvant taxane regimen as long as it has been 12 months since completion of regimen.
9. Patients either may or may not have a prior anthracycline containing regimen.
10. Prior hormonal therapy as a treatment of metastatic disease is allowed. But antitumoral hormonal therapy must be terminated prior to enrollment(up to the date of randomization)
11. Prior radiation therapy allowed as long as \< 25% of the bone marrow has been treated, and the patients must have recovered from the acute toxic effects of the treatment prior to study enrollment. Prior radiation to the whole pelvis is not allowed. Prior radiotherapy must be completed 2 weeks before study entry.
12. Bisphosphonates for the treatment of bone metastases should not be initiated following the first dose of randomized therapy. It must be initiated prior to day of treatment (cycle 1, day 1). Patients may continue on bisphosphonates who already established on bisphosphonate therapy for bone metastases
13. Adequate bone marrow function (≥ ANC 1,500/ul, ≥ platelet 100,000/ul, ≥ Hemoglobin 9.0 g/dl)
14. Adequate renal function (≤ serum creatinine 1.5 mg/dl or CCr ≥ 50 ml/min)
15. Adequate liver function (≤ serum bilirubin 1.5 mg/dl, ≤ AST \& ALTX3 upper normal limit or AST and ALT ≤ 5.0XULN if judged by the investigator to be related to liver metastases)
16. Written informed consent

Exclusion Criteria:

1. Serious uncontrolled intercurrent infections
2. Serious intercurrent medical or psychiatric illness, including active cardiac disease
3. Pregnancy or breast feeding
4. Second primary malignancy(except in situ carcinoma of the cervix or adequately treated nonmelanomatous carcinoma of the skin or other malignancy treated at least 5 years previously with no evidence of recurrence)
5. Documented parenchymal or leptomeningeal brain metastasis
6. Peripheral neuropathy ≥ grade 2
7. Prior treatment with gemcitabine will not be allowed.
8. HER-2 overexpressing breast cancer and concomitant trastuzumab treatment is not allowed
9. Women of childbearing potential, unwilling to use a medically acceptable method of contraception during the trial

• DERIVEDKim JY, Lee E, Park K, Im SA, Sohn J, Lee KS, Chae YS, Kim JH, Kim TY, Jung KH, Park YH; Breast Cancer Committee of the Korean Cancer Study Group. Exploratory biomarker analysis from a phase II clinical trial of eribulin plus gemcitabine versus paclitaxel plus gemcitabine for HER2-negative metastatic breast cancer patients (KCSG BR13-11). Breast Cancer Res Treat. 2019 Nov;178(2):367-377. doi: 10.1007/s10549-019-05400-y. Epub 2019 Aug 12. PMID 31407230
• DERIVEDPark YH, Im SA, Kim SB, Sohn JH, Lee KS, Chae YS, Lee KH, Kim JH, Im YH, Kim JY, Kim TY, Lee KH, Ahn JH, Kim GM, Park IH, Lee SJ, Han HS, Kim SH, Jung KH; Korean Cancer Study Group (KCSG). Phase II, multicentre, randomised trial of eribulin plus gemcitabine versus paclitaxel plus gemcitabine as first-line chemotherapy in patients with HER2-negative metastatic breast cancer. Eur J Cancer. 2017 Nov;86:385-393. doi: 10.1016/j.ejca.2017.10.002. Epub 2017 Nov 5. PMID 29100193