Neoadjuvant dual anti-HER2 therapy for early breast cancer: where do we stand?

摘要

The recent published PEONY trial in the JAMA Oncology by Shao et al. reported a multicenter, double-blind, placebo-controlled randomized phase 3 trial studying the efficacy, safety and tolerability of pertuzumab along with trastuzumab and docetaxel in Asian patients with HER-2 positive non-metastatic breast cancer greater than 2 cm (1). Three hundred and twenty-nine patients were enrolled in the trial. Patients received 4 cycles of 3-weekly anti-HER2 therapy along with docetaxel in the neo-adjuvant setting followed by surgery followed by 3 cycles of FEC (fluorouracil, epirubicin and cyclophosphamide) and then 13 cycles of anti-HER2 therapy (similar to the one they received pre-surgery). The primary endpoint, pathologic complete response (pCR) rate demonstrated a statistically significant difference of 39.3% in the pertuzumab and trastuzumab group against a pCR of 21.8% in the placebo group (trastuzumab only). There was only a slightly higher incidence of serious adverse events in the pertuzumab group of 10.1% vs. 8.2% in the placebo group. The study design was clear and sound. pCR rate in a neo-adjuvant setting is a relevant prognostic endpoint with quick result and suggestion of a possible clinical gain.