Safety and efficacy of gemcitabine and trastuzumab in HER2-directed therapy pretreated patients with HER2-positive metastatic breast cancer: SBP-01 study.

142 Background: Prognosis of HER2-positive metastatic breast cancer (MBC) has been dramatically improved by trastuzumab (Tmab). More recently, newer anti-HER2 agents such as lapatinib, pertuzumab and T-DM1 have prolonged survival. Despite the efficacy of these drugs, most patients develop progressive disease during or after treatment, and alternative anti-HER2 agents plus chemotherapies are required in subsequent lines of treatment. However, there are few evidence on efficacy of Tmab-containing regimens after disease progression. Gemcitabine (GEM) is non-cross resistant to anthracycline and taxane. Preclinical studies have shown that the combination of Tmab and GEM has synergistic effect against HER2-positive breast cancer cell lines. SBP-01 study assessed the efficacy and safety of the combination of Tamb and GEM in patients with HER2-positive MBC previously treated with anti-HER2 therapy. Methods: SBP-01 study included patients treated with one or more anti-HER2 directed regimens for MBC. Patients were ...