Biomarker Duo sTILs + TNBC-DX Flags 91% pCR With PD-1/Carbo-Taxane in Early TNBC

Pembrolizumab, a PD-1 antibody, combined with neoadjuvant docetaxel-carboplatin (TCb + Pem) in the Phase II NeoPACT study (NCT03639948, n = 115) for stage I-III triple-negative breast cancer delivered a 58% overall pCR and 3-year EFS of 86%, with Grade ≥3 TRAEs ≤4% (diarrhea, anemia, neuropathy) and one treatment-related death. When stromal TILs were ≥30% and the TNBC-DX genomic score signaled “pCR-high,” 91.3% of patients (~40% of the cohort) achieved pCR—beating the historical 45-55% seen with TCb aloneand matching the anthracycline-containing KEYNOTE-522 regimen (64.8% pCR, 78% Grade ≥3 AEs).