FDA Advisory Committee Recommends Shield Blood Test Approval for CRC Screening

• The FDA’s Medical Devices Advisory Committee recommends the Guardant Health’s Shield blood test for colorectal cancer (CRC) screening.

• The committee voted favorably on the safety, effectiveness, and overall benefit of the Shield test for average-risk adults aged 45 and older.

• Shield offers a noninvasive alternative to existing stool-based CRC screening methods and its performance is comparable to existing stool tests.

The FDA’s Medical Devices Advisory Committee has given the greenlight to the Guardant Health’s Shield blood test for CRC screening in average-risk adults aged 45 and older.¹

This recommendation suggests that the committee believes the test is safe and effective in its proposed intended use. Additionally, they believed the benefits of this noninvasive screening option outweigh any potential downsides.

Colorectal cancer,medical illustration.3d illustration : © anatomy insider - stock.adobe.com

“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,” said AmirAli Talasaz, co-chief executive officer of Guardant Health, in a press release. “Despite the importance of detecting CRC 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 noninvasive stool tests can increase the rate of colorectal screening and potentially reduce preventable CRC deaths.”

The Shield test is a qualitative, in vitro, diagnostic test which aims to detect CRC which stemmed from cell-free DNA alterations in blood collected with the Guardant Blood Collection Kit. It is recommended that patients with an “Abnormal Signal Detected” may have CRC or advanced adenomas and should be referred for colonoscopy evaluation. The press release notes that Shield is not a replacement for diagnostic or surveillance colonoscopy for patients at high risk of developing CRC.

The advisory committee panel members voted on 3 questions focused on Shield’s use in patients who met the proposed indication. In an 8-to-1 vote, the panel gave reasonable assurance that Shield is safe. A 6-to-3 vote showed the panel’s reasonable assurance that Shield is effective. Lastly, in a 7-to-2 vote, the panel believed that the benefits of Shield outweigh its risks.

Findings from the observational ECLIPSE study (NCT04136002) which were published in The New England Journal of Medicine support this recommendation as Shield had an 83.1% CRC detection sensitivity rate (95% CI, 72.2%-90.3%).² Shield also showed good specificity (89.6%), meaning that 89.6% of patients without advanced colorectal neoplasia detected by colonoscopy had a negative Shield result (95% CI, 88.8%-90.3%). Shield’s performance is comparable to existing stool-based CRC screening tests, which have overall sensitivity rates ranging from 67% to 92%.¹

“Sadly, 76% of deaths caused by CRC occur in individuals who are not up to date with their screening,” Daniel Chung, MD, a gastroenterologist at Massachusetts General Hospital and a professor of medicine at Harvard Medical School, both in Boston, added in the press release. “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.”

It is expected that the FDA will decide on Shield’s approval later in 2024.

REFERENCES:

1. FDA advisory committee panel strongly recommends approval of Shield blood test for colorectal cancer screening as a primary non-invasive screening option. News release. Guardant. May 23, 2024. Accessed May 29, 2024. https://tinyurl.com/m3eh7m22

2. Chung DC, Gray DM 2nd, Singh H, et al. A cell-free DNA blood-based test for colorectal cancer screening. N Engl J Med. 2024;390(11):973-983. doi:10.1056/NEJMoa2304714