Taxane + SC Pertuzumab/Trastuzumab Scores 86% pCR in Node-Negative HER2+/HR⁻ Early Breast Cancer (DECRESCENDO)

Neoadjuvant weekly taxane plus fixed-dose subcutaneous pertuzumab-trastuzumab for 12 weeks yielded pCR (ypT0/Tis N0) in 113/131 patients (86%) with 15–50 mm, node-negative, hormone-receptor-negative HER2-positive tumors in the single-arm phase II DECRESCENDO trial (n = 139). Median age was 58 y; 51% were grade 3. Patients achieving pCR received antibody maintenance only, while residual-disease cases (14%) moved to adjuvant T-DM1 ± anthracyclines. Among baseline samples, 81% of pCRs were PAM50 HER2-enriched. No new safety signals emerged, and the study halted early for slow accrual. For context, the NeoSphere THP + docetaxel regimen reports ~45% pCR overall and ~60% in HR-negative disease—far below the 86% seen here, despite anthracycline sparing.

https://aacrjournals.org/clincancerres/article/31/12_Supplement/P3-11-03/753048/Abstract-P3-11-03-De-escalation-of-chemotherapy-in