Background: The combination therapy of Bevacizumab (B) and Paclitaxel (P) has demonstrated to prolong progression free survival (PFS) in E2100 study. Because its PFS is very long, developing optimal therapeutic strategy of B+P, including management of toxicity is crucial. At the 1st International Consensus Conference for Advanced Breast Cancer, most experts agreed the maintenance endocrine therapy after effective induction chemotherapy. In KBCSG-TR 1214 study, we planned to examine the following clinical questions. 1. As a maintenance therapy, which is more effective either endocrine therapy alone (E) or endocrine therapy with Capecitabine (E+C)? 2. Can maintenance therapy reduce toxicity of B+P and restore patient's QOL.? 3. How effective is B+P re-challenge after failure of maintenance therapy?

Methods: KBCSG-TR 1214 study is multicenter open-labeled randomized phaseII trial for HR-positive and HER2-nagative metastatic breast cancer(MBC) patients. Patients will receive B (10mg/kg q2w) in combination with P (90mg/m2 on day 1, 8, and 15 q4w) as an induction therapy. Patients without progression after 6 cycles of B+P will be randomized to E or E+C. Endocrine therapy will be chosen by their physician (treatment of physician's choice). Patients in E+C will receive endocrine therapy with Capecitabine 1657mg/m2 on day1 to 21 q4w. Stratification factors for randomization are menopausal status, presence of target lesion, number of prior endocrine therapies for MBC, with or without 1st line chemotherapy for MBC. After progression of maintenance therapy (E or E+C), B+P will be started again as a reintroduction therapy. Primary end point is PFS of maintenance therapy. Secondary end points include time to failure of strategy from randomization, efficacy of reintroduction therapy, overall survival and safety of induction therapy. Translational research is also planned. VEGF, angiopoetin-1, and apelin in plasma will be measured at four points (before induction therapy, at the beginning of the maintenance therapy and the re-induction therapy, and at the end of the trial). This study has just begun and planned 120 patients will be enrolled. (UMIN000008662).

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT3-1-01.