Epirubicin plus low-dose trastuzumab in HER2 positive metastatic breast cancer

Purpose This phase II study, evaluated the activity and cardiotoxicity of first-line epirubicin plus low-dose trastuzumab (LD-T) in patients with HER2 positive MBC. Methods Patients received epirubicin 90 mg/sqm every 3 weeks plus weekly LD-T (2 mg/kg loading dose, then 1 mg/kg). After 6/8 cycles of epirubicin, single agent trastuzumab was continued. Cardiotoxicity was defined as signs or symptoms of congestive heart failure (CHF), or ≥15% decline in LVEF without symptoms, or <15% LVEF decline to less than 50%, without symptoms. Results Forty-five patients were enrolled. Twenty-three received prior adjuvant anthracyclines. Overall response rate was 61.4%. The median time to progression was 7.4 months and the median survival was 32.8 months. Two (4.5%) patients developed CHF. Conclusions Epirubicin plus LD-T is an active regimen, however, the relatively high rate of cardiotoxicity together with the availability of less cardiotoxic and active trastuzumab-containing combinations precludes further evaluation of this regimen.