FDA Panel Recommends Approval of DNA-Based Colon Cancer Test
Testing demonstrates 92% sensitivity
The Molecular and Clinical Genetics Panel of the FDA’s Medical Devices Advisory Committee has voted unanimously (10–0) to recommend approval of Cologuard, a stool-based DNA, non-invasive colorectal cancer screening test.
The FDA usually follows the recommendations of its advisors, although it is not required to do so.
In the pivotal DeeP-C trial, the Cologuard test detected 92.3% of colorectal cancer in average-risk patients, based on a combination of DNA and hemoglobin markers.
The test’s developer (Exact Sciences, Inc.) submitted the final module of its pre-market approval (PMA) application for Cologuard in June 2013. That application included data from the DeeP-C study, which was published online March 19 in the New England Journal of Medicine. The study will also appear in the journal’s April 3 print issue.
In the Deep-C trial, a total of 12,776 participants were enrolled at sites in the U.S. and Canada; 9,989 of these subjects (78.2%) had results that could be fully evaluated.
Stool DNA testing identified 60 of 65 participants with colorectal cancer, including 56 of the 60 participants with screening-relevant cancers, for sensitivities of 92.3% and 93.3%, respectively. Sensitivity did not vary significantly according to cancer stage or location within the colon. Among 757 participants with advanced precancerous lesions, DNA testing identified 321 (42.4%). A total of 69.2% of 39 participants with high-grade dysplasia and 42.4% of 99 participants with sessile serrated polyps measuring 1 cm or larger were identified.
DNA testing also detected 13 of 60 screening-relevant cancers that were undetected by the fecal immunochemical test (FIT), whereas FIT detected one cancer that was undetected by DNA testing (P < 0.001). In addition, DNA testing detected 170 of 757 advanced precancerous lesions (22.5%) that were undetected by FIT, whereas FIT detected 29 such lesions (3.8%) undetected by DNA testing (P < 0.001).