The U.S. Food and Drug Administration (FDA) approved the first liquid biopsy companion diagnostic test 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 a deadly form of metastatic non-small cell lung cancer (NSCLC), according to a press release from the FDA.
“Approval of a companion diagnostic that uses a liquid biopsy and leverages next-generation sequencing marks a new era for mutation testing,” said Tim Stenzel, MD, PhD, Director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health. He added, “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 assay – Guardant360 CDx from Guardant Health, located in Redwood City, CA – utilizes two technologies. The first is called liquid biopsy, which uses a blood sample to provide healthcare professionals with genetic information about the patient’s tumor. It is less invasive and more easily repeatable than standard tissue biopsies.
The second technology is NGS, which uses large-panel genetic sequencing, known as high-throughput tumor profiling. Compared to older technologies, NGS requires only one test to allow clinicians to assess tumor composition, giving them an advantage in evaluating which mutations are problematic. The Guardant360 CDx assay uses NGS technology to simultaneously detect mutations in 55 tumor genes, rather than one gene at a time.
While the Guardant360CDx can provide information on multiple solid tumor biomarkers, the FIDA said its approval is specific to its use in identifying EGFR mutations in patients who will benefit from treatment with TAGRISSO (osimertinib), an FDA-approved therapy for a form of metastatic NSCLC. Lung cancer is the leading cause of cancer-related death among men and women in the United States, and NSCLC is the most common type of lung cancer.
