CAP TODAY Pathology/Laboratory Medicine/Laboratory Management
December 2020—The FDA approved the Guardant360 CDx assay (Guardant Health), a liquid biopsy companion diagnostic that also uses next-generation sequencing technology to identify patients with specific types of mutations of the epidermal growth factor receptor gene in a deadly form of metastatic non-small cell lung cancer. This is the first approval to combine NGS and liquid biopsy in one diagnostic test in order to guide treatment decisions.
The Guardant360 CDx assay is approved to provide information on multiple solid tumor biomarkers and to help identify EGFR mutations in patients who will benefit from treatment with Tagrisso (osimertinib), an FDA-approved therapy for a form of 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 the NSCLC mutations are present.