On January 4, the U.S. Food and Drug Administration (FDA) approved FoundationOne Liquid CDx to be used as a companion diagnostic to identify patients with ROS1-positive non–small cell lung cancer (NSCLC) or NTRK fusion–positive solid tumors who do not have a tissue sample available and may be appropriate candidates for treatment with the tyrosine kinase inhibitor entrectinib. FoundationOne Liquid CDx is the first and only blood-based companion diagnostic approved for entrectinib; with this latest approval, it is now approved as a companion diagnostic for nine targeted therapies.
FoundationOne Liquid CDx is a qualitative, next-generation sequencing–based, in vitro diagnostic test for prescription use only that uses targeted high throughput hybridization-based capture technology to analyze 324 genes utilizing circulating cell-free DNA isolated from plasma derived from anticoagulated peripheral whole blood of patients with advanced cancer.
Comprehensive genomic profiling has transformed the traditional ‘one-size fits-all’ approach to cancer and is an important tool for identifying rare and hard-to-find mutations, including ROS1 and NTRK. NSCLC is the most common type of lung cancer, accounting for 80% to 85% percent of all lung cancer diagnoses; ROS1 gene fusions are seen in 1% to 2% of these NSCLC diagnoses. NTRK gene fusions are also rare, occurring in roughly 0.3% of all solid tumors; however, these can be found in many tumor types including breast, cholangiocarcinoma, colorectal, gynecologic, neuroendocrine, non–small cell lung, salivary gland, pancreatic, sarcoma, and thyroid cancers.
