Tuesday, the FDA's staff reviewers raised concerns regarding Guardant Health Inc's ( GH ) experimental blood test for colorectal cancer, suggesting it might not detect some tumor types that could become cancerous. 

Guardant Health ( GH ) is seeking approval for Shield, a blood-based colorectal cancer (CRC) screening test for average-risk adults. 

Shield is an in vitro diagnostic device intended for the qualitative detection of CRC through sequencing the cell-free DNA (cfDNA) isolated from whole blood.

Related: Cancer Test Focused Guardant Health Stock Falls On FDA AdCom Update For Colorectal Test.

The FDA document noted, "Patients with advanced neoplasia (AA) have a high risk of developing CRC cancer. The Guardant ECLIPSE study demonstrated 83.1% sensitivity for CRC but only 13.2% sensitivity for the detection of AA."

The FDA's Molecular and Clinical Genetics Panel is scheduled to meet on Thursday, 23 May, to review the premarket approval application for the company's Shield blood test for colorectal cancer screening.

Despite this, the reviewers acknowledged the test's potential benefits, noting that it could improve compliance with colorectal cancer screenings and aid in early detection, potentially curing patients and extending survival rates.

If approved, Guardant's Shield test could become the second blood-based colorectal cancer test available in the United States.

Colorectal cancer affects approximately 150,000 people in the U.S. annually and is the second-leading cause of cancer deaths in the country, claiming over 50,000 lives each year. 

The screening market for colorectal cancer in the U.S. is valued at nearly $20 billion. 

Despite advancements, about 60 million people, or 50%, remain unscreened, Reuters noted, citing TD Cowen analyst.

The U.S. Centers for Medicare and Medicaid Services (CMS) has stated it would reimburse blood-based biomarker colorectal cancer tests that show a minimum sensitivity of 74%, pending FDA approval.

In contrast, the first blood biomarker test for colorectal cancer, Epigenomics' Epi proColon, was approved by the FDA in 2016 but was not reimbursed by the CMS in 2021 due to its 68.2% sensitivity. 

Epigenomics, now owned by New Day Diagnostics and rebranded as ColoHealth, highlights the competitive landscape for Guardant's Shield as it seeks approval and potential market entry.

Price Action: GH shares are down 2.62% at $24.12 at last check Tuesday.

Image by PDPics from Pixabay