Phase II Study With the Trifunctional Antibody Ertumaxomab to Treat Metastatic Breast Cancer After Progression on Trastuzumab Therapy

This study is an open-label, non-randomized, uncontrolled, two-stage phase II study evaluating the efficacy and safety of ertumaxomab. Ertumaxomab will be administered three times at 7 day intervals by constant rate 3 hour intravenous (i.v.) infusions according to the following dose schedule: 10 µg (day 0); 100 µg (day 7 ± 1 day) and 100 µg (day 14 ± 1 day) (flat doses).