The U.S. Food and Drug Administration (FDA) has approved a new blood test developed by Guardant Health to detect colorectal cancer.
The test, named Shield, provides a less invasive and more convenient option compared to traditional methods, such as fecal tests and colonoscopy, which are currently considered the gold standard.
The FDA’s approval allows Shield to be used for adults aged 45 and older who are at average risk for colorectal cancer.
This marks a critical step forward in expanding screening options for a disease that is both common and deadly.
Colorectal cancer is the second leading cause of cancer fatalities in the United States, claiming over 50,000 lives each year. It also remains the third most common cancer diagnosed in both men and women, with an estimated 106,590 new cases expected in 2024.
Shield has been available since 2022 as a laboratory-developed test (LDT), a category of tests designed, manufactured, and used within a single laboratory.
However, FDA approval moves Shield closer to becoming the first blood test for colorectal cancer screening eligible for Medicare coverage.
This could make the test more accessible to older adults, potentially covering costs for those aged 65 and older under certain Medicare plans.
The approval is based on a study published in the New England Journal of Medicine, which demonstrated that Shield detected colorectal cancer in 83% of patients at average risk who were not experiencing symptoms.
While this sensitivity rate is slightly lower than the 92.3% achieved by the stool-based Cologuard test from Exact Sciences, Shield offers the advantage of being a simple blood test. This ease of use, free from the “ick factor” associated with stool tests, could encourage more people to get screened.
Dr. Jon LaPook, CBS News‘ chief medical correspondent and a gastroenterologist at NYU Langone Health, highlighted that while Shield is a promising tool, it does not replace colonoscopy. Colonoscopy not only detects cancer but also allows for the removal of precancerous polyps, a crucial step in preventing cancer development.
However, Shield can serve as a complementary tool, especially for those hesitant to undergo colonoscopy.
Colorectal cancer is increasingly affecting younger populations, with a rising number of cases among those under 50. In response, screening guidelines have been adjusted, lowering the recommended starting age from 50 to 45. This shift aims to catch cancer earlier, increasing the chances of successful treatment.
Guardant Health’s co-CEO, AmirAli Talasaz, described the FDA approval as a “significant victory for patients” and an important milestone in the company’s mission to combat cancer through innovative data solutions.
With Shield now available by prescription, it offers a new pathway for early detection and potentially life-saving intervention.