Large-Scale Study Shows Guardant360 Effectively Guides Precision Oncology Treatment in Metastatic Breast Cancer Patients

Data presented at 2019 San Antonio Breast Cancer Symposium demonstrates the value of blood-based comprehensive genomic profiling in metastatic breast cancer

REDWOOD CITY, Calif., Dec. 13, 2019 (GLOBE NEWSWIRE) -- In the largest-ever liquid biopsy study for treatment selection in advanced breast cancer, investigators demonstrated in an 800-patient prospective clinical trial that the Guardant360 assay accurately detected biomarkers that can guide targeted treatment.¹ The use of a blood test provided comprehensive genotyping for late stage breast cancer patients, many with bone metastases that are often difficult to biopsy and typically yield insufficient material for biomarker analysis.²

The study, plasmaMATCH, sponsored by the Institute of Cancer Research London, demonstrated that Guardant360 had 96%-99% overall concordance with digital droplet PCR (ddPCR) liquid biopsy, an orthogonal method. Guardant360 also detected significantly more targetable alterations than hotspot testing, including over 35 percent more PIK3CA mutations¹ that can now be effectively targeted by recently FDA approved therapies.³ Guardant360 also detected significantly more ESR1 mutations and found previously undetected microsatellite instability (MSI) and ERBB2 amplifications and mutations, all of which are clinically actionable mutations. The findings were presented at the 2019 San Antonio Breast Cancer Symposium.

“The plasmaMATCH study results, mark an important step towards establishing liquid biopsies, such as Guardant360, as the new standard of care to non-invasively detect patient subgroups with advanced breast cancer who will be sensitive to targeted therapies particularly if their cancer evolves to become drug resistant,” said Professor Nicholas Turner, PhD, lead investigator, Professor of Molecular Oncology at the Institute of Cancer Research, London, and Consultant Medical Oncology at The Royal Marsden. “We have now confirmed that liquid biopsies can quickly give us a bigger picture of what mutations are present within multiple tumours throughout the body, while also getting the results back to patients accurately and faster than we ever could before.”