BACH: A randomized phase II trial of doxorubicin-cyclophosphamide (AC) versus pegylated liposomal doxorubicin (PLD)-cyclophosphamide-trastuzumab (CCH) followed by paclitaxel-trastuzumab (TH) as adjuvant therapy for HER2-positive breast cancer (BC)—Cardiac safety analysis.

559 Background: For patients (pts) with HER2+ BC, concurrent AC-H results in unacceptable cardiotoxicity rates. Substituting PLD for A in an adjuvant regimen may minimize cardiotoxic risk and permit earlier integration of adjuvant H. Methods: Inthis randomized phase II trial, pts with resected lymph node+ or high-risk, node-negative HER2+ BC were stratified by age and randomized (1:2) to: Arm A: AC (60/600 mg/m2 q21d × 4) followed by T 80 mg/m2 + H 2 mg/kg qwk × 12 or Arm B: PLD 35 mg/m2 + C 600 mg/m2 q21d × 4 + H 2 mg/kg/wk × 12, followed by T 80 mg/m2 + H 2 mg/kg qwk × 12. Subsequent H for a total of 1y was given as per institutional standards. Primary objective was incidence of level 1 (cardiac death or severe heart failure with left ventricular ejection fraction [LVEF] drop > 10% to 10% to < 50%) cardiac event rates during the 8 cycles of chemotherapy (CT). This analysis reports cardiotoxicity for the entire patient population comple...