Phase 3 trial: neoadjuvant anbenitamab with albumin-bound docetaxel raised pathological complete response in HER2-positive breast cancer to 62.4%

In a phase 3 randomized trial in 521 patients with stage II-III HER2-positive breast cancer, neoadjuvant anbenitamab (a biparatopic HER2 antibody) with albumin-bound docetaxel achieved a total pathological complete response in 62.4% of patients (164/263) versus 51.2% (132/258) with standard trastuzumab, pertuzumab and docetaxel — an absolute difference of 11.4 percentage points (95% CI 3.2-19.6; P=.004). Grade 3-4 treatment-related adverse events were comparable between arms (29.3% versus 28.3%) and there were no treatment-related deaths. The endpoint reached here is pathological response after preoperative treatment, not survival; whether the advantage translates into fewer recurrences or longer life requires longer follow-up.