Last week, Guardant Health released the results of ECLIPSE, a three-year clinical trial with over 20,000 participants aged 45-84 (https://lnkd.in/eDKhAeP6). The clinical trial focused on Shield, previously known as Lunar-2, the company’s blood-based colorectal cancer screening test for use in average risk adults. In this study, two configurations of a multimodal blood-based screening test were evaluated independently – a cell-free DNA (cfDNA)-only test and a cfDNA test with protein biomarkers. The publicly released results were derived from the cfDNA-only test, which outperformed the cfDNA test with protein biomarkers.
Guardant reported that Shield demonstrated 83% sensitivity and 90% specificity, compared with the gold standard diagnostic method, colonoscopy, which the company stressed exceeded the 74% sensitivity and 90% specificity performance criteria set by Medicare in a national coverage determination. In comparison, Exact Sciences’ FDA-approved, stool DNA-based test, Cologuard, has 92% sensitivity and 87% specificity. Lastly, Guardant’s Shield test showcased only 13% sensitivity in detecting advanced adenomas, while Exact’s test shows 42%. This has raised some concerns for Shield test regarding potential FDA approval and labeling such that if FDA would modify labeling to exclude claims for advanced adenomas or limit the test use.
Investors signaled their disappointment in Guardant’s study results through a sudden drop in Guardant’s stock values late Thursday and early Friday while Exact Sciences saw their stock values climb.
Goldbug will continue to monitor for updates around this technology and other similar initiatives.