Summary: The FDA’s Medical Devices Advisory Committee recommended approval of Guardant Health’s Shield blood test for colorectal cancer screening.


  1. The FDA panel voted favorably on the test’s safety, effectiveness, and benefit-risk profile.
  2. The Shield blood test’s ease of use with a simple blood draw may overcome barriers associated with stool-based tests, potentially increasing colorectal cancer screening adherence among average-risk individuals.
  3. The earlier ECLIPSE study demonstrated Shield’s high sensitivity (83%) and specificity (90%) for detecting colorectal cancer, comparable to existing non-invasive stool tests.

Guardant Health announced the Molecular and Clinical Genetics Panel of the U.S. Food and Drug Administration (FDA)’s Medical Devices Advisory Committee has recommended FDA approval of the company’s Shield blood test for colorectal cancer (CRC) screening in adults age 45 and older who are at average risk for the disease.

The recommendation signals the advisory committee panel’s consensus on Shield’s safety and effectiveness with its proposed intended use, and their conclusion that its benefits as a primary non-invasive screening option outweigh any potential risks, according to Guardant Health. The FDA is expected to decide whether to approve Shield later this year.

“The advisory committee’s strong support for the approval of Shield reinforces the crucial role that a blood test option can have in improving CRC screening rates for those at average risk,” says AmirAli Talasaz, co-CEO of Guardant Health. “Despite the importance of detecting colorectal cancer early, there are notable barriers that can deter average-risk Americans from completing existing screening methods. Shield effectively detects cancer at an early stage when it is most treatable. Providing people with this blood test alongside other non-invasive stool tests can increase the rate of colorectal screening and potentially reduce preventable CRC deaths.”

Advisory Committee Panel on the Shield Test

The advisory committee panel members voted on three questions regarding the use of Shield in patients who meet the criteria specified in the proposed indication. They voted eight to one favorably that there is reasonable assurance Shield is safe, six to three favorably that there is reasonable assurance Shield is effective, and seven to two favorably that the benefits of Shield outweigh its risks.

Scope of Colorectal Cancer

Colorectal cancer is the second-leading cause of cancer-related deaths in the U.S.(2) yet has a 91% five-year survival rate when caught at stage I (localized).(3) Despite this, one out of three eligible Americans – 50 million people – are not being screened for CRC.(4) Current primary non-invasive screening options include stool-based tests which have proven efficacy in detecting CRC; however, studies have consistently found that barriers such as handling stool and challenges performing the test impact adherence.(5,6,7,8) Shield offers patients a choice that can be completed with a simple blood draw during a routine office visit, the company says.

“Sadly, 76% of deaths caused by colorectal cancer occur in individuals who are not up to date with their screening,”(9) says Daniel Chung, MD, gastroenterologist at Massachusetts General Hospital and Professor of Medicine at Harvard Medical School. “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.”

The panel’s recommendation is based on Guardant’s premarket approval (PMA) application for Shield, including the results of the ECLIPSE study evaluating the performance of the test for detecting CRC in average-risk adults. Results from the study, published in the March 2024 issue of The New England Journal of Medicine, showed that Shield demonstrated 83% sensitivity for the detection of CRC, with 90% specificity for advanced neoplasia. This performance is within range of existing stool-based tests used as primary CRC screening options, in which overall sensitivity ranges from 67% to 92%.(10)


  1. The Shield test meets performance requirements for Medicare coverage under NCD 210.3.
  2. American Cancer Society. Key Statistics for Colorectal Cancer. Accessed online May 21, 2024.
  3. American Cancer Society. Survival Rates for Colorectal Cancer. Accessed online May 21, 2024.
  4. National Colorectal Cancer Roundtable. 80% in Every Community. Accessed May 21, 2024.
  5. Raymond V, Foster G, Hong Y et al. Implementation of Blood-Based Colorectal Cancer Screening: Real-World Clinical Experience. ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.
  6. Denberg TD, Melhado TV, Coombes JM, et al. Predictors of Nonadherence to Screening Colonoscopy. J Gen Intern Med. 2005;20(11):989-995.
  7. Gellad ZF, Stechuchak KM, Fisher DA, et al. Longitudinal Adherence to Fecal Occult Blood Testing Impacts Colorectal Cancer Screening Quality. Am J Gastroenterol. 2011;106(6):1125-1134.
  8. Inadomi JM, Vijan S, Janz NK, et al. Adherence to Colorectal Cancer Screening: A Randomized Clinical Trial of Competing Strategies. Arch Intern Med. 2012;172(7):575-582.
  9. Doubeni, CA, et al. Modifiable Failures in the Colorectal Cancer Screening Process and Their Association with Risk of Death. Gastroenterology. 2019 Jan; 156(1): 63–74.e6.