Pertuzumab Plus Trastuzumab and Chemotherapy for Patients With HER2-Positive Early Breast Cancer
According to final results from the phase 3 APHINITY trial, the addition of adjuvant pertuzumab to trastuzumab and chemotherapy improved outcomes among patients with operable human epidermal growth factor receptor 2 (HER2)-positive early breast cancer.
These results were first presented by Sibylle Loibl, MD, PhD, Goethe University of Frankfurt, Frankfurt, Germany, at the 2025 European Society for Medical Oncology (ESMO) Breast Cancer Annual Congress in Munich, Germany.
In this double-blind study, 4804 patients were enrolled to receive adjuvant pertuzumab (n = 2400) or placebo (n = 2404) plus trastuzumab and chemotherapy. The primary end point was overall survival (OS). Key secondary end points included invasive disease-free survival (iDFS) and safety.
At a median follow-up of 11.3 years, the 10-year OS rate was 91.6% in the pertuzumab arm and 89.8% in the placebo arm (hazard ratio [HR] 0.83; 95% confidence interval [CI], 0.69 to 1.00; P = .044). The HR for OS was 0.79 in the node-positive subgroup, 0.99 in the node-negative subgroup, 0.76 in the hormone receptor (HR)-positive subgroup, and 0.94 in the HR-negative subgroup. In the pertuzumab arm 303 iDFS events occurred compared to 379 iDFS events in the placebo arm. The 10-year iDFS rates were 87.2% and 83.8%, respectively (HR 0.79; 95% CI, 0.68 to 0.92). The HR for iDFS was 0.74 in the node-positive subgroup, 1.01 in the node-negative subgroup, 0.75 in the HR-positive subgroup, and 0.87 in the HR-negative subgroup. The incidence of primary cardiac safety events remained < 1%. Four hundred and fifty-two deaths occurred on study, with 205 deaths in the pertuzumab arm and 247 deaths in the placebo arm.
“These final OS results, with long-term follow-up, further support the benefit of [pertuzumab] in the early breast cancer setting,” concluded Dr Loibl et al.
Source:
Loibl S, Piccart M, Clark E, et al. Adjuvant pertuzumab or placebo + trastuzumab + chemotherapy (P or Pla + T + CT) in patients (pts) with early HER2-positive operable breast cancer in APHINITY: Final analysis at 11.3 years’ median follow-up. Presented at the 2025 ESMO Breast Cancer Annual Congress. May 14-17, 2025. Abstract LBA1
