On August 7, 2020, the U.S. Food and Drug Administration (FDA) approved the Guardant360 CDx assay as the first liquid biopsy companion diagnostic that also uses next-generation sequencing (NGS) technology to identify patients with specific types of mutations of the epidermal growth factor receptor (EGFR) gene in patients with metastatic non-small cell lung cancer (NSCLC). This is the first approval to combine two technologies in one diagnostic test to guide treatment decisions. 

FDA Approves First Liquid Biopsy NGS Companion Diagnostic Test for NSCLC

“Approval of a companion diagnostic that uses a liquid biopsy and leverages NGS marks a new era for mutation testing,” Tim Stenzel, MD, PhD, director of the Office of In Vitro Diagnostics and Radiological Health in FDA’s Center for Devices and Radiological Health, said. “In addition to benefitting from less invasive testing, patients are provided with a simultaneous mapping of multiple biomarkers of genomic alterations, rather than one biomarker at a time, which can translate to decreased wait times for starting treatment and provide insight into possible resistance mechanisms.” 

The Guardant360 CDx assay’s liquid biopsy technology uses a blood sample to provide healthcare professionals with genetic information about a tumor. It is less invasive and easier to repeat than standard tissue biopsies and can be used when standard tissue biopsies are not feasible, such as because of a tumor’s location. 

The Guardant360 CDx assay uses NGS technology to simultaneously detect mutations in 55 tumor genes through large-panel genetic sequencing, known as high-throughput tumor profiling. Compared to older technologies, NGS requires only one test to give clinicians a better assessment of tumor composition.  

Although the Guardant360 CDx can provide information on multiple solid tumor biomarkers, the FDA approval is specific to identifying EGFR mutations in patients who will benefit from treatment with osimertinib (Tagrisso®) for metastatic NSCLC. Genomic findings for other biomarkers evaluated are not validated for choosing a particular corresponding treatment with this approval. If the specific NSCLC mutations associated with this approval are not detected in the blood, then a tumor biopsy should be performed to determine if NSCLC mutations are present. 

FDA granted the Guardant360 CDx assay breakthrough device designation. A description of FDA expedited programs is in the Guidance for Industry—Expedited Programs for Serious Conditions—Drugs and Biologics

Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System or by calling 800-FDA-1088.    

For assistance with single-patient oncology investigational new drug applications, contact the Oncology Center of Excellence’s Project Facilitate at 240-402-0004 or email OncProjectFacilitate@fda.hhs.gov