Guardant Health and PICI Launch Research Collaboration To Study Connection Between Cancer Biomarkers and Immunotherapy Treatment Response

• Project will identify genomic and epigenomic biomarkers in patient blood samples from PICI’s RADIOHEAD study using GuardantINFINITY™
• Goal of mission-focused collaboration is to help accelerate development and utilization of immune therapies for cancer

PALO ALTO & SAN FRANCISCO — Guardant Health, Inc. (Nasdaq: GH), a leading precision oncology company, and the Parker Institute for Cancer Immunotherapy (PICI), a network of the largest concentration of immuno-oncology (IO) expertise in the world, today announced a research collaboration agreement to study the correlation between molecular cancer biomarkers and patient response to immunotherapy treatment across more than 14 different types of cancer.

Under the agreement, Guardant Health will analyze patient blood samples from PICI’s RADIOHEAD (Resistance Drivers for Immuno-Oncology Patients Interrogated by Harmonized Molecular Datasets) prospective study of 1,200 individuals on standard-of-care immune checkpoint inhibitor (ICI) treatment regimens in community hospitals. The testing, which will be conducted with GuardantINFINITY, will provide a multi-dimensional analysis of each patient’s tumor response based on both genomic and epigenomic profiling. The study will use blood samples drawn at multiple points during the treatment regimen and will assess the connection between the presence of specific cancer biomarkers and real-world clinical outcomes, including survival and immune-related adverse events.

“By breaking down barriers and forging deep collaboration, PICI can accelerate the development of breakthrough immune therapies and turn all cancers into curable diseases,” said Tarak Mody, PhD, Chief Business Officer at PICI. “This mission-focused collaboration with Guardant Health aims to identify the molecular drivers of treatment response in clinical practice, provide significant learnings in PD1 resistance mechanisms and serve as a valuable resource to the PICI research network for biomarker discovery, target validation and clinical trial design.”

The project marks the first real-world immuno-oncology study collaboration for Guardant Health and will enable the company to significantly expand its access to real-world outcomes data for immunotherapies correlated to specific biomarkers, cancer type and stage.

“The collaborative study with PICI is an excellent opportunity for us to explore the value of genomic and epigenomic tumor profiling in real-world immuno-oncology therapy settings,” said Helmy Eltoukhy, Guardant Health chairman and co-CEO. “The study will generate deeper insights about the tumor microenvironment and its response to therapy, which will enable us to respond to cancer evolution faster and, eventually, modify immunotherapy treatment paradigms for better patient outcomes.”

Guardant Health and PICI intend to begin publishing data generated by the study later in 2023.

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 GuardantINFINITY™ tests for advanced-stage cancer, and Guardant Reveal™ for early-stage cancer. The Guardant Health screening portfolio, including the Shield^TM test, aims to address the needs of individuals eligible for cancer screening. For more information, visit guardanthealth.com and follow the company on LinkedIn and Twitter.

About the Parker Institute for Cancer Immunotherapy

The Parker Institute for Cancer Immunotherapy (PICI) is radically changing the way cancer research is done. Founded in 2016 through a $250 million gift from Silicon Valley entrepreneur and philanthropist Sean Parker, the San Francisco-based nonprofit is an unprecedented collaboration between the country’s leading immunotherapy researchers and cancer centers. The PICI Network of research institutions includes Dana-Farber Cancer Institute, Gladstone Institutes, Stanford Medicine, the University of California, Los Angeles, the University of California, San Francisco and the University of Pennsylvania. The institute also supports top researchers at other institutions, including City of Hope, Fred Hutchinson Cancer Center, Icahn School of Medicine at Mount Sinai, Institute for Systems Biology, Memorial Sloan Kettering Cancer Center, The University of Texas MD Anderson Cancer Center and Washington University School of Medicine in St. Louis. By forging alliances with academic, industry and nonprofit partners, PICI makes big bets on bold research to fulfill its mission: to accelerate the development of breakthrough immune therapies to turn all cancers into curable diseases. Find out more at parkerici.org, and follow us on LinkedIn and Twitter @parkerici.

About RADIOHEAD

The RADIOHEAD (Resistance Drivers for Immuno-Oncology Patients Interrogated by Harmonized Molecular Datasets) program is a pan-tumor, prospective cohort study of 1,200 individuals on standard of care first-line immune checkpoint inhibitor treatment regimens aiming to identify drivers of immune related adverse events and clinical response. This real-world study captured a comprehensive profile of each participant by collecting blood samples and clinical features at pretreatment, early on-treatment and late timepoints from 52 community oncology clinics across the United States. Molecular and multiomic profiling of these longitudinal samples and associated clinical data points provides an opportunity to identify clinically actionable mechanisms for immunotherapy resistance and adverse events.

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, 2022, 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.