Research highlights the significance of genomic and epigenomic profiling approaches to characterize lung tumors, identify biomarkers, and support risk stratification
Real-world studies examine the complementary roles of plasma- and tissue-based testing, including data from Asia and the Middle East
Educational symposium and expert panel discussion to provide insights on the expanding role of plasma-based ctDNA throughout the patient journey

Guardant Health, Inc. (NASDAQ:GH), a leading precision oncology company, today announced that the company and its research collaborators will present 20 abstracts—including one mini oral presentation—showcasing advances in methylation-based tumor classification and liquid biopsy technology across lung cancer subtypes at the 2026 World Conference on Lung Cancer (WCLC). The conference is hosted by the International Association for the Study of Lung Cancer (IASLC) and will take place September 12–15, 2026, in Seoul, South Korea.

The studies span Guardant's lung cancer portfolio, including tissue-free molecular residual disease (MRD) surveillance, treatment-response and resistance research, and investigational early-detection. Several studies were conducted independently by leading academic institutions and industry collaborators using Guardant technologies and/or real-world data, underscoring the broad adoption of Guardant's platform across the research community.

Key data that will be presented include:

Mini Oral, Abstract MO12.04: exploring the ability of longitudinal plasma ctDNA profiling — leveraging the Guardant INFINITY^™ assay, one of two ctDNA profiling platforms used — to characterize acquired resistance to sevabertinib in advanced HER2-mutant non-small cell lung cancer (NSCLC), identifying secondary HER2 T862A as the predominant resistance-associated alteration while noting that most progressing patients lacked an identifiable genomic resistance driver.
Abstract EP04.14: evaluating the ability of the Guardant Shield^™blood test to complement low-dose CT screening for earlier, more consistent lung cancer diagnosis.
Abstract P2.237: analyzing clinical trial biomarkers through plasma ctDNA profiling in the Phase III FLAURA2 trial evaluating baseline co-mutations and acquired resistance mechanisms in EGFR-mutated advanced NSCLC.
Abstract P2.222: using a proprietary machine-based learning model and Guardant360^® data to predict 90-day brain metastasis risk in lung adenocarcinoma, outperforming molecular-only approaches.
Abstract P2.096: providing real-world analysis of tissue-free Guardant Reveal^® in patients with NSCLC across the AMEA region, supporting the feasibility of MRD testing to accurately and efficiently detect disease in routine clinical practice.

"We look forward to engaging with top thoracic oncologists from across the globe and sharing insights on the power of our methylation-based technology combined with the limitless potential of InfinityAI," said Helmy Eltoukhy, Guardant Health chairman and co-CEO. "Our expanded presence at this meeting reflects our dedication to ongoing research and product development to better identify and treat lung cancer through blood-based biopsy."

Selected Guardant Health and collaborator presentations at WCLC 2026

Presentation	Title	Time
P2.184 Poster	Impact of Common Resistance Mechanisms on Real-World Overall Survival (rwOS) for Patients Receiving Osimertinib	September 13, 2026 10:30 AM - Noon KST
P1.102 Poster	ctDNA Longitudinal Risk Stratification in NSCLC Using Multiple MRD Platforms in Real-World Analysis	September 13, 2026 10:30 AM - Noon KST
P2.222 Poster	Machine Learning-Derived cfDNA Clinico-Methylation Signature Predicts Brain Metastasis Risk in Lung Adenocarcinoma	September 14, 2026 10:30 AM - Noon KST
P2.123 Poster	Concordance of Detecting EGFR Mutation by Liquid Biopsy Versus Tissue Biopsy for Stage III NSCLC	September 14, 2026 10:30 AM - Noon KST
P2.095 Poster	Real-World Performance of Plasma ctDNA Epigenomic Subtyping of Lung Cancer in Asia and the Middle East	September 14, 2026 10:30 AM - Noon KST
P2.238 Poster	Early On-Treatment Prediction of Long-Term PFS Using a Joint AI-imaging and ctDNA Model in the CROWN Study	September 14, 2026 10:30 AM - Noon KST
P2.096 Poster	Real-world Utilization of Tissue-free Molecular Residual Disease (MRD) Testing in Lung Cancer Patients from Asia-Pacific and Middle East (AMEA)	September 14, 2026 10:30 AM - Noon KST
P2.237 Poster	Baseline Co-Mutations and Acquired Resistance Mechanisms in EGFR-Mutated Advanced NSCLC: FLAURA2 Exploratory Analysis	September 14, 2026 10:30 AM - Noon KST
MO12.04 Mini Oral	Molecular Landscape of Acquired Resistance to Sevabertinib in HER2-mutant NSCLC: Exploratory Biomarker Analysis of SOHO-01	September 15, 2026 11:25 - 11:30 AM KST
EP04.14 ePoster	EARLY: Earlier Detection of Lung Cancer with Liquid Biopsy in Patients with Solitary Pulmonary Nodules and Ground-Glass Opacities	September 15, 2026 11:55 PM KST

Guardant Health will also sponsor a one-hour symposium on the clinical interpretation of plasma-based methylation signals in advanced NSCLC:

From Plasma to Practice: Clinical Interpretation of Methylation Signals in Advanced NSCLC

Day: Monday, September 14, 2026

Time: 1:45–2:45 PM KST

Location: Room 103, Grand Ballroom, 1F, COEX Convention & Exhibition Center

The expert panel leading the symposium includes:

Dr. Natasha Leighl (Panel Chair) - Princess Margaret Cancer Center, Toronto, Canada
Professor Nir Peled - Shaare Zedek Medical Center, Jerusalem, Israel
Dr. Charu Aggarwal - University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
Dr. Christian Rolfo - The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA

The full abstracts for Guardant Health and a list of all abstracts being presented at WCLC 2026 can be found on the WCLC website.

About Guardant360^® Liquid

Guardant360 Liquid is a blood-based test that analyzes tumor DNA fragments circulating in the blood (cfDNA) to identify genetic mutations in advanced solid tumors, helping oncologists find targeted therapies. It offers an alternative to tissue biopsies, providing comprehensive genomic profiling (CGP) to guide personalized treatment for a wide range of solid cancers including lung, breast, colorectal, and prostate cancer. Guardant360 Liquid is guideline-complete across all advanced solid tumors, and has been clinically validated in more than 1,500 publications and research abstracts.

About Guardant Reveal^®

Guardant Reveal is a tissue-free liquid biopsy test that detects minimal residual disease (MRD) and monitors recurrence in early-stage colorectal, breast, and lung cancers, helping oncologists guide treatment decisions. In addition to MRD detection, Reveal can be used for late-stage therapy response monitoring for patients with solid tumors. Guardant Reveal therapy response monitoring can be initiated at any time during a patient’s treatment journey, offering clinicians flexibility and actionable insights.

The first clinical-validation study of pan-cancer chemotherapy monitoring published in The Journal of Liquid Biopsy showed that Guardant Reveal predicts long-term patient benefit up to 18 months earlier than standard clinical measures.

About Shield^™

Shield is a methylation partitioning cell-free DNA (mp-cfDNA) non-invasive, blood-based screening test that detects alterations associated with colorectal cancer in the blood. It is intended as a screening test for individuals at average risk for the disease, age 45 or older, and is not intended for individuals at high risk for colorectal cancer. The Shield test can be considered in a manner similar to guideline-recommended non-invasive CRC screening options and can be completed during any healthcare visit. A positive Shield result raises concern for the presence of colorectal cancer or advanced adenoma and the patient should be referred for colonoscopy evaluation.

About Guardant Health

Guardant Health is a leading precision oncology company focused on guarding wellness and giving every person more time free from cancer. Founded in 2012, Guardant is transforming patient care and accelerating new cancer therapies by providing critical insights into what drives disease through its advanced blood and tissue tests, real-world data and AI analytics. Guardant tests help improve outcomes across all stages of care, including screening to find cancer early, monitoring for recurrence in early-stage cancer, and treatment selection for patients with advanced cancer. For more information, visit guardanthealth.com and follow the company on LinkedIn, X (Twitter) and Facebook.

Guardant Health 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, 2025 and in its other reports filed with or furnished to 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.

View source version on businesswire.com: https://www.businesswire.com/news/home/20260909640093/en/

Investor Contact:

Zarak Khurshid

investors@guardanthealth.com

Media Contact:

Meaghan Smith

press@guardanthealth.com