Press release
Phase III PALLAS Study Shows Signatera™ MRD Testing Provides Powerful Post‑Surgical Prognostic Information in Patients with High and Intermediate Risk HR+/HER2‑ Breast Cancer
MRD status after surgery stratifies patients beyond established clinical and genomic risk tools AUSTIN, Texas--(BUSINESS WIRE)-- Natera, Inc. (NASDAQ: NTRA),
About this update from Natera, Inc.
[{"type":"text","content":"\nMRD status after surgery stratifies patients beyond established clinical and genomic risk tools\n\n AUSTIN, Texas--(BUSINESS WIRE)--\nNatera, Inc. (NASDAQ: NTRA), a global leader in cell-free DNA and precision medicine, together with Alliance Foundation Trials, LLC (AFT) and the Austrian Breast and Colorectal Cancer Study Group (ABCSG), today announced initial translational research results from the international randomized Phase III PALLAS study.\n\nPresented today at the San Antonio Breast Cancer Symposium (SABCS), these first data, generated from a U.S. biomarker cohort of 420 patients, show that molecular residual disease (MRD) status, measured by the Signatera Genome test after surgery (and adjuvant chemotherapy +/- radiation if administered), is a highly prognostic biomarker for distant recurrence risk in stage II–III, HR+/HER2- breast cancer. The findings support Natera’s strategy to integrate MRD testing into routine post‑surgical risk assessment, enabling a more personalized approach to managing early-stage HR+ breast cancer. Data from a parallel ex-US cohort will be presented in conjunction with a treatment subgroup analysis at a later date.\n\nIn PALLAS, patients with stage II–III HR+/HER2- breast cancer were randomized to receive two years of palbociclib, a CDK4/6 inhibitor, in combination with endocrine therapy. Signatera MRD assessments were performed after surgery at three key postoperative timepoints: on the first day of protocol-directed experimental therapy (baseline), on-treatment at approximately 6 months (C6D1), and at the end of the 2-year interventional treatment period (EOT). Key findings from this initial analysis include:\n\nSignatera correctly identified patients with low risk of recurrence.\n\n\nAt baseline, approximately 92% of patients were MRD-negative and had excellent outcomes, with 5-year distant recurrence-free interval (DRFI) of 93%. Measured starting at EOT, MRD-negative patients had a 5-year DRFI of 95%. This underscored that MRD-negativity after surgery and adjuvant endocrine therapy is associated with an exceptionally low risk of distant recurrence.\n\n\nMRD-positive patients had very poor outcomes with current therapy.\n\n\nBaseline MRD positivity was observed in roughly 8% of this stage II–III HR+/HER2- population. These patients had 5-year DRFI of 28%, corresponding to a markedly elev...