The FDA’s decision means that oncologists can use FoundationOne Liquid CDx to identify patients with ROS1-positive non–small cell lung cancer or NTRK fusion–positive solid tumors who are eligible for treatment with entrectinib.
The FDA has granted companion diagnostic designation to FoundationOne Liquid CDx to help in identifying ROS1-positive non–small cell lung cancer (NSCLC) or NTRK fusion–positive solid malignancies that may be treated with entrectinib (Rozlytrek), according to a press release from Foundation Medicine.1
FoundationOne Liquid CDx is a next-generation sequencing–based in vitro diagnostic that analyzes 324 genes via circulating cell-free DNA by targeting throughput hybridization-based plasma derived from anti-coagulated peripheral whole blood in a population with advanced disease.
The approval makes the assay the first and only liquid companion diagnostic for entrectinib.
“With the most FDA-approved companion diagnostic claims of any blood-based comprehensive genomic profiling test, FoundationOne Liquid CDx is an accessible tool for evidence-based, guideline-adherent therapy selection,” Mia Levy, chief medical officer at Foundation Medicine, said in the press release. “Liquid biopsies can make molecular testing possible for patients when tissue is not available and we’re excited that just over 6 months after the approval of our tissue-based test as a companion diagnostic for [entrectinib], our blood-based test can now also be offered to support doctors in connecting their patients with this targeted treatment option."
The assay is capable of reporting variants in more than 300 genes and could identify patients who may potentially benefit from certain therapeutics. Notably, a negative result from the test does not necessarily rule out a mutation status and additional testing should be conducted using tissue-based assays, if possible.
The FDA approved the tissue-based FoundationOne CDx assay in June 2022 as a companion diagnostic for entrectinib in patients with potential ROS1 fusion–positive or NTRK fusion–positive NSCLC.2 The approval was based on 3 clinical trials: phase 1 ALKA-372-001, phase 1 STARTRK-1 (NCT02097810), and phase 2 STARKTRK-2 (NCT02568267) trials.
The ALKA-372-001 study included patients with advanced or metastatic solid malignancies; the STARTRK-1 study included a population with TrkA, TrkB, TrkC, and ALK altered disease; and the STARTRK-2 study included patients with NTRK1/2/3, ROS1, or ALK fusion–positive disease.
The FDA approved entrectinib as a treatment for NTRK-positive solid tumors and ROS1-positive NSCLC in August 2019.3 The regulatory decision was supposed by findings from both the STARTRK-1 and STARKTRK-2 trials.