- FDA Friday approved Guardant Health's liquid biopsy diagnostic that uses next-generation sequencing (NGS) to identify patients with mutations of the epidermal growth factor receptor (EGFR) gene in metastatic non-small cell lung cancer. It is the first time the two technologies have been combined in one diagnostic test, the agency said.
- The Guardant360 CDx assay was approved as a companion diagnostic to identify patients with EGFR alterations who may benefit from treatment with AstraZeneca's lung cancer drug Tagrisso. Although FDA's approval specifies that the genomic findings are validated for one particular treatment, the test can detect mutations in 55 tumor genes simultaneously.
- Analysts at Cowen wrote in a note to investors Sunday the approval came slightly earlier than they expected. But they noted that since Medicare already reimburses for most advanced solid tumors "FDA approval should boost [Guardant's] negotiations with private payers, maybe increase [average selling prices], and improve [Guardant's] marketing position."
Liquid biopsies, which detect cancer biomarkers in the blood, offer a faster, noninvasive diagnostic alternative to tissue biopsies for analyzing genetic material and can guide personalized treatment for late-stage cancers.
Guardant reported sales growth of 23% in the second quarter, a slowdown from the 84% first-quarter pace before COVID-19 disrupted typical patterns of healthcare. However, investors expect liquid biopsies to gain momentum in the pandemic due to the advantage of being less invasive, ultimately benefiting the company and competitor Exact Sciences.
The next-generation sequencing technology means only one test is needed to assess tumor composition.
Tim Stenzel, director of FDA's Office of In Vitro Diagnostics and Radiological Health, called the clearance "marks a new era for mutation testing."
“In addition to benefiting 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," he added in a statement.
FDA in 2018 singled out Guardant360 as a breakthrough device, a speedier review status it reserves for technologies that serve unmet clinical needs. Guardant said the test received FDA approval based on clinical and analytical validation data from more than 5,000 samples.
Data from the pivotal FLAURA and AURA3 clinical trials in non-small cell lung cancer patients identified for treatment with Tagrisso using the Guardant360 diagnostic showed progression-free survival rates consistent with those identified using traditional biomarker testing, Guardant said. Guardant360 also is being studied as a companion diagnostic for products in development by other collaborators, including Amgen, Janssen Biotech and Radius Health.
During Guardant's second quarter earnings call on Thursday, Guardant CEO Helmy Eltoukhy said in prepared remarks that clinical volumes for Guardant360 during the quarter grew 15% to 13,694 tests compared to the prior year. Along with obtaining pan-cancer Medicare coverage and demonstrating that liquid biopsy is a viable alternative to tissue testing, FDA approval of Guardant360 with a pan-cancer tumor profiling label has been among Guardant's foremost goals.
The Cowen note to clients outlined that Guardant360 will be reimbursed under the existing CMS national coverage determination for comprehensive genetic profiling using NGS, which analysts said "most likely supports initial reimbursement at ~$3,500." Coverage for the test currently stands at at least 170 million lives, according to the analysts.
FDA's approval order notes that the test uses circulating cell-free DNA (cfDNA) from plasma of peripheral whole blood collected in Streck Cell-Free DNA Blood Collection Tubes, a product given De Novo authorization by the agency the same day as the Guardant360 approval.