NEW YORK – Guardant Health said Friday that the US Food and Drug Administration has approved its targeted next-generation sequencing liquid biopsy assay, Guardant360 CDx, for tumor mutation profiling in advanced cancer patients with any solid malignant neoplasm.
The agency also approved a companion diagnostic indication for the test to identify non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor alterations who may benefit from treatment with osimertinib (AstraZeneca's Tagrisso).
Guardant said the approval was based on clinical and analytical validation data from more than 5,000 samples. In a retrospective analysis of data from two pivotal phase III clinical trials, FLAURA and AURA3, NSCLC patients identified for treatment with osimertinib using the Guardant360 CDx demonstrated progression-free survival rates consistent with those identified using traditional tissue-based biomarker testing.
In its own statement, the FDA specified that other biomarkers evaluated by the 55-gene Guardant360 CDx panel are not validated for choosing a particular corresponding treatment under the current approval. As it has with approvals of previous single-gene liquid biopsy assays, the agency also specified that if the relevant NSCLC mutations are not detected in the blood by Guardant's test it doesn't necessarily mean patients don't have them in their tumors. In light of this, physicians should seek out follow-up tumor tissue testing in such cases.
Guardant said the non-FDA-approved, laboratory-developed version of its assay has been used by more than 7,000 oncologists in the US, with more than 150,000 individual tests performed to date since it was introduced several years ago.
The company has increased its efforts recently to establish a "blood-first" paradigm for comprehensive genomics in the precision oncology community, working to persuade clinicians that liquid biopsy testing can help get more patients on potentially beneficial targeted drugs more quickly and efficiently.
"Traditional tissue biopsy-based tumor profiling, which is often invasive and has longer turnaround times, can contribute to delays in starting treatment and possibly suboptimal therapy," Guardant CEO Helmy Eltoukhy said in a statement. "We are confident that our FDA approval will help accelerate wider adoption of guideline-recommended genomic profiling, increase the number of advanced cancer patients who receive potentially life-changing treatments, and pave the way for new companion diagnostic developments," he added.
In recent years the FDA had approved several tissue-based NGS assays for both tumor profiling and specific companion diagnostic claims. But the Guardant approval is the first of this kind for a liquid biopsy platform.
"Approval of a companion diagnostic that uses a liquid biopsy and leverages next-generation sequencing marks a new era for mutation testing," Tim Stenzel, director of the Office of In Vitro Diagnostics and Radiological Health in the FDA's Center for Devices and Radiological Health, said in a statement.
According to Guardant, its test is also being developed as a companion to investigational products in development by firms like Amgen, Janssen Biotech, and Radius Health. If successful, these projects could lead to additional companion indications for the assay.