Precision oncology diagnostics company Guardant Health announced this week the availability of Shield, the company’s first blood-based test for the detection of early-stage colorectal cancer (CRC). The test is intended for adults age 45 and older who are not up to date with recommended screening guidelines, show no symptoms of CRC, and are at average risk for CRC.
“The availability of the Shield test represents a major milestone in our commitment to transform cancer screening. We have developed highly sensitive technology to detect early-stage cancers with a simple blood draw,” said AmirAli Talasaz, Guardant’s co-CEO. “Colorectal cancer screening is the start of this journey. We will soon expand into multi-cancer screening, including lung, pancreas and others, where we believe cancer screening can save lives.”
Guardant sees the new blood-based test as one that can significantly increase CRC screening rates, as one-third of all adults currently have not completed recommended screening for the disease despite the fact CRC is curable if diagnosed early.
Currently available screening methods, such as a colonoscopy or a stool-based test are time-consuming or difficult to complete. The company believes its the Shield test overcomes these barriers because it requires no special preparation, no sedation, no dietary changes, no extra time away from family or work, and it can be completed as part of a regular clinical office visit.
The Shield assay was validated using a set of 309 patient samples, including 92 with CRC, 51 with advanced adenomas and 166 normal cases. CRC patient samples were from six unique cohorts in the U.S., Canada, and the EU, and samples with advanced adenoma and normal cases were collected in the U.S. Subjects were balanced by age (a mean of 64 years old) and gender. The Shield assay demonstrated 91% sensitivity for CRC, including 90% for Stage I, 97% for Stage II, and 86% for Stage III disease. The assay also demonstrated 20% sensitivity for advanced adenomas and 92% specificity in normal cases.
Clinical case for CRC screening
More than 75% of people who die from CRC today are not up to date with recommended screening. Cancer underscreening is an important factor contributing to the high cancer mortality rate in underserved populations. For example, in the area of CRC, only 59% of individuals age 50 and older who are Hispanic and 65% of individuals who are Black/African American are up to date with recommended screenings, compared to 68% of individuals who are white.
“The value of colorectal cancer screening is well-established for individuals at average risk, age 45 and older,” said J. Leonard Lichtenfeld, MD, MACP, chief medical officer of Jasper Health in a press release. “But the benefits of screening have been limited due to the suboptimal completion rates of stool tests and colonoscopy. A high-sensitivity test that can be completed with a convenient blood draw during any healthcare provider visit can help patients overcome the barriers to adherence and help healthcare professionals identify more cancers at their earliest stages, when they are most treatable.”
Anjee Davis, president of Fight Colorectal Cancer added: “Colorectal cancer is largely preventable if caught early, yet barriers to screening tests remain. These barriers include lack of healthcare access, limited capacity in healthcare systems, transportation challenges, childcare, and lack of paid leave from work. The availability of a test like this is a welcomed addition to the tools we can use to prevent cancer. This has the potential to improve access to screening for underserved populations and dramatically improve overall screening rates.”
