Non-Invasive Colorectal Cancer Screening Test Approved by FDA Panel

Preliminary FDA advisory panel recommends approval of a stool DNA-based colorectal cancer screening test based on favorable study results.

The Molecular and Clinical Genetics panel of the US Food and Drug Administration (FDA) Medical Devices Advisory Committee unanimously voted last week to recommend the FDA approval of Exact Science’s Cologuard, a stool-based DNA (sDNA) colorectal cancer screening test. Although the FDA is not required to adhere to the panel’s

recommendations, it often strongly considers its views during the approval process.

The panel based its recommendations on results from a study involving 10,000 patients conducted across 90 sites in the US. Investigators reported that sDNA testing detected significantly more cancers in asymptomatic persons at average risk for colorectal cancer compared with fecal immunochemical tests (FIT) — about 20%. The study was published in the April 3, 2014, print issue of the New England Journal of Medicine

The sDNA testing is based on a combination of DNA and hemoglobin markers. Cologuard found 92% of colorectal cancers in average-risk patients, compared with a 74% sensitivity for FIT. sDNA testing also had a higher degree of sensitivity when detecting early-stage colorectal cancer (93% vs. 73%) and when detecting advanced pre-cancerous lesions (42% vs. 24%). However, sDNA testing generated more false positives compared to FIT testing.

“We are pleased the committee strongly supported Cologuard's approval,” Kevin T. Conroy, chairman and chief executive of Exact Sciences, said in a statement. “We look forward to continuing our work with the FDA to complete its review of Cologuard and remain committed to addressing the growing unmet needs in colorectal cancer screening.”