SignateraTM MRD Identifies Breast Cancer Patients Who Can Forgo Surgery

Prospective study published in Clinical Cancer Research shows that women >70 who tested Signatera MRD-negative could avoid surgery and remain progression-free

AUSTIN, Texas--(BUSINESS WIRE)--Natera, Inc. (NASDAQ: NTRA), a global leader in cell-free DNA and precision medicine, today announced a publication in Clinical Cancer Research showing that Signatera was able to identify older women with early-stage ER+/HER2- breast cancer who can be managed with primary endocrine therapy (pET), without surgery.

While pET can be an alternative to surgery for patients with early breast cancer, tools for risk stratification and monitoring have been limited. This prospective study enrolled 43 women, aged 70 and older, with stage 1-3 ER+/HER2- breast cancer who all elected to forgo surgery and receive pET. Patients were tested with Signatera at baseline (pre-treatment), and then every 3-6 months alongside standard imaging and physician assessment. Key results included:

• Pre-treatment (baseline) molecular residual disease (MRD) assessment identified that 68% of patients (23/34) were MRD-negative, among whom zero experienced progression (100% negative predictive value at baseline).
• Among the 11 patients who tested baseline MRD-positive, 64% (7/11) cleared their circulating-tumor DNA (ctDNA) after 6 months of pET, where all 7 remained free of distant progression, and 1 out of 7 experienced locoregional progression that was detected by Signatera in advance of imaging.
• Tumor progression occurred in 5 patients, all of whom tested MRD-positive in advance of imaging (longitudinal sensitivity of 100%).
• Over 80% of patients reported that Signatera helped inform their treatment decisions without increased anxiety.

“Treatment decisions for older patients with breast cancer often require balancing disease control with quality of life, other medical problems and patient preference,” said Priscilla F. McAuliffe, M.D., Ph.D., lead author of the study and a surgical oncologist at the University of Pittsburgh. “The findings from this study suggest ctDNA monitoring with Signatera could help identify patients for whom non-surgical approaches for their breast cancer treatment may be appropriate.”

“This study highlights the role of Signatera as a critical molecular monitoring tool for patients with breast cancer who defer surgery,” said Angel Rodriguez, M.D., senior medical director of oncology at Natera. “By providing an early signal of disease progression that aligns with imaging, Signatera may help physicians monitor treatment response and make more informed care decisions for older patients.”

About Natera

Natera™ is a global leader in cell-free DNA and precision medicine, dedicated to oncology, women’s health, and organ health. We aim to make personalized genetic testing and diagnostics part of the standard-of-care to protect health and inform earlier, more targeted interventions that help lead to longer, healthier lives. Natera’s tests are supported by more than 400 peer-reviewed publications that demonstrate excellent performance. Natera operates ISO 13485-certified and CAP-accredited laboratories certified under the Clinical Laboratory Improvement Amendments (CLIA) in Austin, Texas, and San Carlos, California, and through Foresight Diagnostics, its subsidiary, operates an ISO 27001-certified and CAP-accredited laboratory certified under CLIA in Boulder, Colorado. For more information, visit www.natera.com.

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