FDA Approves Shield Blood Test for Colorectal Cancer Screening

Microscopic image of colorectal cancer cells - Generated with Google Gemini AI

• The FDA has approved Guardant Shield, a blood test to detect cancer in the colon or rectum.
• This approval provides a more convenient alternative to fecal tests for colorectal cancer screening.
• A study showed that shield identified 83% of colorectal cancers.

Guardant Shield is now an FDA-approved blood-based test to detect colorectal cancer (CRC), the second-leading cause of cancer deaths in the US.¹

“Sadly, 76% of deaths caused by colorectal cancer occur in individuals who are not up to date with their screening,”9 said Daniel Chung, MD, gastroenterologist at Massachusetts General Hospital and professor of medicine at Harvard Medical School, said in a press release.² “Clinical evidence and CRC screening guidelines acknowledge the value of offering choice to individuals at average risk for CRC and highlight the role of patient preference in test selection and CRC screening completion.”

In May 2024, the FDA’s Medical Devices Advisory Committee recommended the approval of the Shield test for those 45 and older who are at average risk for CRC.

With this approval, a more convenient option for CRC screening is available compared with feces-based tests like Cologuard, which was approved by the FDA for ages 50 and older in 2014 and ages 45 to 49 in 2019.³

Shield is now the second FDA-approved blood-based CRC test.1 In 2016, Epi proColon was approved for those age 50 or older with average risk of CRC. Clinical trial showed that Epi proColon had a sensitivity of 68.2% (95% CI, 53.4%-80.0%) and a specificity of 80.0% (95% CI, 77.9%-82.1%).⁴

About the Shield Test

Shield is an in vitro diagnostic test to detect CRC-derived alterations in cell-free DNA in the blood.¹ The test is intended for those who are 45 and older at average risk of CRC. If an abnormal signal is detected from the tests, CRC may be present, and a colonoscopy evaluation should be performed.

In March 2024, data published in The New England Journal of Medicine showed that Shield had an 83.1% (95% CI, 72.2%-90.3%) sensitivity for detection of CRC.5 The sensitivity for stages I to III CRC was 87.5% (95% CI, 75.3%-94.1%). For advanced neoplasia, the sensitivity was 89.6% (95% CI, 88.8%-90.3%). Comparatively, existing stool-based diagnostic tests have sensitivity ranging from 67% to 92%.⁵

REFERENCES:

1. US FDA approves Guardant Health’s blood-based cancer test. News release. Reuters. July 29, 2024. Accessed July 29, 2024. https://tinyurl.com/yyu94wk2

2. FDA advisory committee panel strongly recommends approval of ShieldTM blood test for colorectal cancer screening as a primary non-invasive screening option. News release. Guardant Health, Inc. May 23, 2024. Accessed July 29, 2024. https://tinyurl.com/u2ra46v8

3. Cologuard gains FDA approval for use in younger Americans, ages 45 to 49. News release. Exact Sciences Corp. September 23, 2019. Accessed July 29, 2024. https://tinyurl.com/y3ybty4b

4. Epi proColon. Epigenomics. Accessed July 29, 2024. https://tinyurl.com/2e36enm3

5. Chung D, Gray D, Singh H, et al. A cell-free DNA blood-based test for colorectal cancer screening. N Engl J Med. 2024;390:973-983. doi:10.1056/NEJMoa2304714