NEW YORK (GenomeWeb) – Diagnostics firm Metabolomic Technologies (MTI) this week launched sales of its PolypDx colorectal cancer test.
The assay, which uses triple-quad mass spec to measure the levels of three metabolites in patient urine to aid in early detection of adenomatous polyps, is being offered initially as a laboratory-developed test by Atlantic Diagnostic Laboratories (ADL).
MTI signed a deal with ADL in May making that company the exclusive licensee and distributor of the PolypDx test in 11 US states and Washington DC.
PolypDx is intended for use in healthy patients who should, according to standard guidelines, receive regular colonoscopies to check for tumors or precancerous polyps. That includes patients between 50 and 74 who have no family history of the disease, and patients between 40 and 74 who do have a family history.
In a clinical study looking at roughly 1,000 Canadian patients, the test detected adenomatous polyps with sensitivity of 82 percent and a specificity in the 40 percent range, David Chang, MTI's chief operating officer, told GenomeWeb. The high sensitivity means a low level of false negatives, ensuring that the test doesn't miss many patients with polyps. The low specificity, however, does mean the test will likely return a large number of false positives.
This high false positive rate is not as significant a concern as it might be with other tests, though, given that all tested patients should be undergoing colonoscopies anyway.
"These are patients who normally would be scheduled for a colonoscopy but decide, 'Well I feel fine, I'm not going to go,'" Chang said, noting that the test is intended to help drive patient compliance with colonoscopy guidelines, particularly in patients the test identifies as being at high risk of having polyps.
While colorectal cancer is often treatable if detected early, compliance with recommended screening procedures like colonoscopies is relatively low. According to numbers from the US Centers for Disease Control and Prevention, colonoscopies have a 62 percent compliance rate — a blended average that includes both symptomatic and asymptomatic patients.
Several other companies, including Applied Proteomics, Exact Sciences, and Epigenomics offer similar tests. Applied Proteomics released its SimpliPro Colon proteomic test at the end of 2015. Unlike PolypDx, the API test is not a general screening tool but is intended for use in symptomatic patients.
Like PolypDx, Exact Sciences' Cologuard and Epigenomics' Epi proColon tests are intended for colorectal cancer screening in healthy, asymptomatic patients. Both of those tests have received approval from the US Food and Drug Administration.
Chang said that MTI hopes to stand out from this competition by focusing on detection of adenomatous polyps, which precede colorectal cancer. Both Cologuard and Epi proColon are also capable of detecting polyps but are primarily focused on detecting early-stage colon cancer.
"We really feel that for screening detecting cancer is too late," Chang said. "We want to detect the polyps before cancer and prevent cancer from even forming."
A spinout of the University of Alberta, MTI is based in Edmonton, Canada, but initially targeted the US market because it would be able to commercialize the test more quickly as a patient-paid product, he said. To launch the assay in Canada MTI would first need to demonstrate its beneficial health economics to secure uptake within that country's public healthcare system.
The company will no doubt need similar health economic data to secure reimbursement for the test in the US, which will likely prove key to its ultimate success. Chang said MTI is currently putting together such studies in the Canadian market and also aims to collect this sort of data as it deploys the test in the US.
Chang said the company plans to sell PolypDx for $399 per test, though he noted that could vary state to state. By way of comparison, Applied Proteomics' SimpliPro Colon lists for $448 and Exact Sciences' Cologuard lists for $599.
MTI developed the test using NMR as its original discovery platform. NMR has certain advantages over mass spec, Chang noted, in particular ease of sample prep.
"You basically just put [the sample] into the machine, and NMR allows you to do a broad spectrum sweep," he said. "So it doesn't matter what class of analytes, whether they are polar or non-polar, it kind of all just goes in there."
NMR is not typically a clinical platform, however, and Chang said that MTI realized that if they wanted to partner with US-based CLIA labs to offer the test, they would have to move it to a different format. They decided to develop a commercial version of the test on a triple-quad using multiple-reaction monitoring assays.
While MRM-MS technology has only in recent years become a viable clinical tool for proteomic tests, the approach has long been used for clinical measurements of small molecules, including metabolites. Compared to protein assays, metabolite assays typically require less complicated sample prep given that steps like trypsin digestion aren't required.
ADL helped develop the commercial version of the test, Carl Selavka, ADL's toxicology director, told GenomeWeb. He said that turnaround time for the test would typically be around 48 hours but that his lab would be able to process the test in as little as two hours when needed.
In addition to PolypDx, MTI is working on its ColoDx test, which is intended for detection of colorectal cancer specifically. The company also has active research programs in diseases such as breast and prostate cancer.
MTI is privately funded and currently has nine employees, Chang said.