An open-label safety study of lapatinib plus trastuzumab plus paclitaxel in first-line HER2-positive metastatic breast cancer.

Background: Recent data support the hypothesis that combining lapatinib and trastuzumab with taxane chemotherapy may offer added clinical benefit to patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC). This study examined the safety of the triplet combination in first-line HER2-positive MBC.

Patients And Methods: Patients were enrolled into three sequential cohorts; the last two cohorts were added by protocol amendment following review of safety data from cohort 1.