Clinical Summary: 

• Design/Population: In this phase 3 trial, patients with HER2-positive early or locally advanced breast cancer were randomized to receive neoadjuvant anbenitamab plus nab-docetaxel with or without carboplatin or standard trastuzumab, pertuzumab, and docetaxel with or without carboplatin.
• Key Outcomes: Anbenitamab-based therapy significantly improved total response compared with standard HER2-directed therapy while maintaining a comparable safety profile.
• Clinical Relevance: These findings support an anbenitamab-based neoadjuvant regimen as a potential new treatment standard for patients with HER2-positive early-stage or locally advanced breast cancer.

Results from a phase 3 trial demonstrated that anbenitamab plus chemotherapy significantly improved total pathologic complete response (pCR) compared with standard neoadjuvant HER2-directed therapy among patients with HER2-positive early or locally advanced breast cancer.

These results were presented by Zhi-Ming Shao, PhD, Fudan University Shanghai Cancer Center, Shanghai, China, at the American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois.

In this study, 521 patients were randomized 1:1 to receive 6 cycles of anbenitamab plus nab-docetaxel with or without carboplatin or trastuzumab, pertuzumab, and docetaxel with or without carboplatin. Randomization was stratified according to clinical stage, hormone receptor status, and planned carboplatin use. The primary end point was total (pCR), assessed via blinded independent central review. 

At analysis, pCR rate was 62.5% in the anbenitamab arm and 51.2% in the control arm (P = .0036). The benefit was consistent across prespecified subgroups, including those defined by hormone receptor status, clinical stage, and planned carboplatin use. Breast pCR was 64.6% in the anbenitamab arm and 55% in the control arm (P = .0099).

Treatment-emergent adverse events were reported in 98.5% of patients in the anbenitamab arm and 98.8% of patients in the control arm. Grade ≥3 treatment-emergent adverse events were reported in 29.3% and 28.3% of patients, respectively. The most frequently reported events included neutropenia and leukopenia. Treatment-emergent adverse events led to interruptions in 5.7% of patients in the anbenitamab arm and 7.4% of patients in the control arm, and permanent discontinuations in 4.9% of patients and 3.5% of patients, respectively. 

“These results support Anbenitamab-based regimen as a potential new standard of care,” concluded Dr Shao. 

Source: 

Shao ZM, Ji P, Liu T, et al. Anbenitamab plus albumin-bound docetaxel (nab-docetaxel) ± carboplatin (Cb) versus trastuzumab and pertuzumab plus docetaxel (THP) ± Cb as neoadjuvant therapy for HER2-positive early or locally advanced breast cancer: A randomized, open-label, multicenter, phase 3 trial. Presented at the ASCO Annual Meeting. May 29 - June 2, 2026. Chicago, Illinois. LBA660.