Anbenitamab plus albumin-bound docetaxel in patients (pts) with HER2-positive advanced breast cancer (BC): A randomized phase III study

Anbenitamab + HB1801 vs THP in HER2+ ABC

Patient / Population Intervention / Exposition Comparaison Critère de jugement

In previously untreated HER2-positive advanced breast cancer, anbenitamab plus albumin-bound docetaxel improved progression-free survival by blinded independent review compared with THP.

N

885patients

Schéma

Multicentre, randomised, open-label phase 3 trial in patients with histologically confirmed HER2-positive advanced breast cancer and no prior chemotherapy or HER2-directed therapy for advanced disease, randomised 1:1 to anbenitamab plus HB1801 (albumin-bound docetaxel) or THP, stratified by prior adjuvant/neoadjuvant therapy, hormone receptor status and visceral metastases (NCT05838066).

Critère

Progression-free survival assessed by blinded independent review committee (BIRC).

RésultatAt the prespecified interim analysis (401 PFS events), median PFS by BIRC was not reached (95% CI 24.9-NE) with anbenitamab plus HB1801 vs 14.3 months (95% CI 12.4-16.4) with THP (HR 0.46; 95% CI 0.37-0.56; P<0.0001). Investigator-assessed PFS HR 0.52 (95% CI 0.43-0.64). Confirmed ORR by BIRC 87.6% vs 73.4%, with median duration of response not reached (95% CI 27.0-NE) vs 16.6 months (95% CI 12.5-20.8). Grade ≥3 treatment-related adverse events occurred in 36.9% vs 25.3%, most commonly neutropenia (13.1% vs 8.4%). Treatment-related deaths: 1 vs 2.

Xu B, Wang J, Li H, et al. Presented at ESMO Congress 2026, abstract LBA15, 24 October. Not yet published.

Discussion et critique

This large randomised trial shows a substantial PFS benefit over THP by blinded central review, supported by investigator assessment and a higher response rate. The results come from an interim analysis with the experimental-arm median not reached, no median follow-up reported, and overall survival immature and described only as a trend, with no figures given. The trial was open label and the experimental arm differs from THP in both the HER2-directed agent and the chemotherapy, so the contribution of anbenitamab alone cannot be separated. Grade ≥3 treatment-related adverse events were more frequent with anbenitamab (36.9% vs 25.3%), which sits uneasily with the authors' description of a favourable safety profile.