A noninvasive, multitarget stool RNA test called ColoSense showed significant improvements in sensitivity compared with the standard fecal immunochemical test (FIT) and similar or better results than the Cologuard test in a Phase III trial led by the Washington University School of Medicine.
ColoSense, developed by U.S. biotech Geneoscopy, was able to accurately detect colorectal cancer and advanced adenomas in 94% and 46% of stool samples, respectively, compared with a sensitivity of 78% and 29% for the FIT test.
The ColoSense test did have a higher rate of false positives than the FIT test with a specificity rate of 88% vs 96%, respectively, although this rate was still well above the acceptable FDA minimum of 80%.
Colorectal cancer is an increasing problem in the U.S., causing over 52,000 deaths a year. Screening is very effective at picking up cancerous lesions at an early stage and significantly improves survival, but the invasive nature of colonoscopies as a screening method results in less than 60% of people attending screening appointments.
The FIT test uses antibodies to search for low levels of blood in the stool that may indicate early signs of colorectal cancer. This test is commonly used in many countries around the world as a first step test to assess whether people should also have a colonoscopy screen.
Other more accurate non-invasive tests have been developed, most notably Exact Sciences Cologuard test, a mt-sDNA test, which is currently the most accurate biomarker test for colorectal cancer approved by the FDA. It has a 92% sensitivity for detecting any colorectal cancer and a 42% sensitivity for detecting advanced adenomas in those aged 50 and older.
The current study, published in JAMA, tested Geneoscopy’s ColoSense mt-sRNA test in 8920 participants aged 45 years or older from across the U.S. who all submitted stool samples for the FIT test and the ColoSense test before undergoing colonoscopy to evaluate the findings of the two non-invasive tests.
The participants were aged 55 years on average with 4% identifying as Asian, 11% as Black and 7% as Hispanic. Overall, 36 individuals in the cohort had colorectal cancer and 606 had advanced adenomas. In addition, 649 had medium-risk adenomas, and 2284 had low-risk adenomas.
The ColoSense test achieved a sensitivity of 96% for detecting colorectal cancer, with 34 of 36 people with the condition detected. It also detected 278 out of 606 people with advanced adenomas, achieving a sensitivity of 46%. The detection rate of ColoSense for low- or medium-risk adenomas or no findings was 88%.
“This study leads to several conclusions to improve colorectal cancer screening,” write the authors. “The mt-sRNA test can be an effective noninvasive test that is sensitive for colorectal cancer and advanced adenomas, with a comparable level of false-positive results compared with existing molecular screening tests. Moreover, the test characteristics in a younger cohort (45–49 years), now recommended for screening, is preserved.”
Geneoscopy has already submitted pre-marketing approval to the FDA for ColoSense, based on the favorable results of this study and others.
