Study Shows Guardant360® Liquid Biopsy Test Helps Guide Treatment for Patients with HER2-Driven Metastatic Colorectal Cancer

November 11, 2021

The study, published in Nature Medicine, demonstrates that the Guardant360® test helps identify patients who may benefit from treatment and can identify alterations that predict resistance

REDWOOD CITY, Calif.--(BUSINESS WIRE)-- Guardant Health, Inc. (Nasdaq: GH), a leading precision oncology company, announced today that a study published in Nature Medicine reinforces the benefits of using the Guardant360® liquid biopsy test to help guide treatment decisions for patients with HER2-driven metastatic colorectal cancer (mCRC). Led by the National Cancer Center Hospital East (NCCHE) in Japan, the study demonstrates that the Guardant360 test can select patients for HER2-directed therapy, identify which patients are responding to treatment, as well as identify genetic alterations that predict resistance.

The Phase 2 TRastuzumab combIned with pertuzUMab for Patients with Her2-positive mCRC (TRIUMPH) study evaluated the efficacy of targeted therapy pertuzumab plus trastuzumab in patients with mCRC harboring HER2 amplification as detected by analysis of circulating tumor DNA (ctDNA) or tissue genotyping. All patients were previously treated with monoclonal antibodies targeting EGFR. Additional exploratory analyses were conducted to evaluate the utility of ctDNA genotyping to predict treatment efficacy, monitor response, and identify the resistance mechanisms.

The study, which follows on last year’s SCRUM-Japan GOZILA study, found that while efficacy of HER2-directed treatment was similar in patients with HER2 amplification detected in tissue or in ctDNA, the ctDNA analysis provided an added benefit of identifying additional alterations that predicted which patients would benefit from HER2-directed therapy. In addition, decreases in ctDNA shortly after treatment initiation corresponded with radiographic response and resistance-related alterations were identified by ctDNA genotyping after disease progression.

“This study demonstrates the clinical utility of the Guardant360 test in helping guide treatment decisions for patients with metastatic colorectal cancer,” said Dr. Yoshiaki Nakamura, NCCHE, principal investigator of the TRIUMPH study. “Based on our results, we believe that ctDNA genotyping is beneficial in clinical practice to identify patients who are most likely to benefit from treatment with pertuzumab plus trastuzumab.”

“Our Guardant360 blood test consistently demonstrates that it is a critical test in not only determining actionable biomarkers, but helping to guide treatment decisions,” said Helmy Eltoukhy, Guardant Health Co-CEO. “This study reinforces the breadth and applicability of our Guardant360 test to help inform clinical decisions for patients with advanced cancer across their treatment journey.”

The Guardant360 liquid biopsy test is part of the market leading Guardant360 portfolio that offers oncologists end-to-end testing solutions from treatment selection to treatment response monitoring. The portfolio includes the Guardant360® CDx test, the first FDA-approved liquid biopsy for comprehensive tumor mutation profiling across all solid tumor cancers, and Guardant360 TissueNext™ to provide oncologists with another option for comprehensive genomic profiling. Also included is Guardant360 Response™, the first blood-only liquid biopsy that enables oncologists to view molecular response, or changes in ctDNA levels, from a simple blood draw to get an early indication of whether a patient is responding to treatment. This tool assists oncologists when considering whether to continue, stop, or explore other treatment options for their patients with late-stage or metastatic cancer.

Since it was first introduced, the Guardant360 blood test has become widely accepted for blood-based comprehensive genomic profiling (CGP) with more than 250 peer-reviewed publications including over 60 clinical outcomes studies. It has been trusted by more than 9,000 oncologists with more than 150,000 tests performed to date.

About Guardant Health

Guardant Health is a leading precision oncology company focused on helping conquer cancer globally through use of its proprietary tests, vast data sets and advanced analytics. The Guardant Health oncology platform leverages capabilities to drive commercial adoption, improve patient clinical outcomes and lower healthcare costs across all stages of the cancer care continuum. Guardant Health has commercially launched Guardant360®, Guardant360 CDx, Guardant360 TissueNext™, Guardant360 Response™, and GuardantOMNI® tests for advanced stage cancer patients, and Guardant Reveal™ for early-stage cancer patients. These tests fuel development of its LUNAR screening program, which aims to address the needs of asymptomatic individuals eligible for cancer screening.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of federal securities laws, including statements regarding the potential utilities, values, benefits and advantages of Guardant Health’s liquid biopsy tests or assays, which involve risks and uncertainties that could cause the actual results to differ materially from the anticipated results and expectations expressed in these forward-looking statements. These statements are based on current expectations, forecasts and assumptions, and actual outcomes and results could differ materially from these statements due to a number of factors. These and additional risks and uncertainties that could affect Guardant Health’s financial and operating results and cause actual results to differ materially from those indicated by the forward-looking statements made in this press release include those discussed under the captions “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operation” and elsewhere in its Annual Report on Form 10-K for the year ended December 31, 2020 and in its other reports filed with the Securities and Exchange Commission. The forward-looking statements in this press release are based on information available to Guardant Health as of the date hereof, and Guardant Health disclaims any obligation to update any forward-looking statements provided to reflect any change in its expectations or any change in events, conditions, or circumstances on which any such statement is based, except as required by law. These forward-looking statements should not be relied upon as representing Guardant Health’s views as of any date subsequent to the date of this press release.


Nakamura, Y., Okamoto, W., Kato, T., et al. Circulating tumor DNA-guided treatment with pertuzumab plus trastuzumab for HER2-amplified metastatic colorectal cancer: a phase 2 trial. Nature Medicine. 11 November 2021.

Investor Contact:
Carrie Mendivil

Media Contact:
Michele Rest

Julie Johnson

Source: Guardant Health, Inc.