Feasibility and Efficacy of Eribulin Mesilate in Korean Patients with Metastatic Breast Cancer: Korean Multi-center Phase IV Clinical Study Results.

PURPOSE: Eribulin mesilate was approved for the treatment of patients with locally advanced or metastatic breast cancer (MBC), who had received at least two chemotherapeutic regimens, including anthracycline and taxane. On the other hand, the efficacy and safety information of eribulin in Korean patients is limited by the lack of clinical trials. MATERIALS AND METHODS: In this multicenter, open-label, single-arm, phase IV study, locally advanced or MBC patients were enrolled between June 2013 and April 2014 from 14 centers in Korea. One point four mg/m2 dose of eribulin was administered on days 1 and 8 of every 21 days. The primary endpoint was the frequency and intensity of the treatment emergent adverse event. The secondary endpoint was the disease control rate, which included the rate of complete responses, partial responses, and stable disease. RESULTS: A total of 101 patients received at least one dose of eribulin and were included in the safety set. The patients received a total of 543 treatment cycles, with a median of three cycles (range, 1 to 31 cycles). The most common adverse event was neutropenia (91.1% of patients, 48.3% of cycles). The frequent non-hematological adverse events included alopecia, decrease in appetite, fatigue/asthenia, and myalgia/arthralgia. The peripheral neuropathy of any grade occurred in 27 patients (26.7%), including grade 3 in two patients. Disease control rate was 52.7% and 51.3% of patients in the full analysis set and per-protocol set, respectively. CONCLUSION: This study demonstrated the feasible safety profile and activity of eribulin in Korean patients with MBC.