ERBB2 and breast cancer: In a phase III clinical trial, locally progressive or metastatic HER2-postive BC patients who had disease progression after prior treatment with anthracyclines, paclitaxel, and trastuzumab and whose LVEF was within the normal range prior to enrollment received lapatinib + capecitabine and maintenance capecitabine alone, respectively; cardiovascular events (defined as asymptomatic heart failure or a ≥20% decrease in LVEF from baseline) remained low in both groups, i.e., at 2.45 and 0.62%, respectively (63).