NEW YORK — Takeda has launched its CDPath prognostic assay in the US aimed at helping Crohn's disease patients understand the severity of their diagnoses and make better decisions on how to manage symptoms and disease progression.
The company said the CDPath blood test uses serologic markers of anti-Saccharomyces cerevisiae antibodies, immunoglobulin A/G isotypes, anti-CBir1 IgG, and perinuclear antineutrophil cytoplasmic antibodies along with the genetic marker NOD2 1007 frameshift mutation, and Crohn's disease history to rank a patient's risk of developing serious complications within three years, with findings that are presented to patients through a graphical interface. It is intended for use in patients at least 18 years old who have been diagnosed with Crohn's within the prior 10 years and have no history of bowel strictures, internal penetrating disease, or non-perianal surgery. The prescription-only test delivers results in about one week, said Tokyo-based Takeda, whose US business is headquartered in Boston.
Crohn's is an incurable inflammatory bowel disease with recurring cycles of flare-ups and remission. Some patients have years of mild symptoms such as diarrhea and stomachache while others spiral into painful and destructive complications such as fistulas, abscesses, and strictures.
It is for differentiating these patients who may need more aggressive treatments from those who may not need treatment at all that Takeda developed and validated the CDPath test in partnership with Prometheus Laboratories and MiTest Health.
San Diego-based Prometheus, a specialty clinical laboratory developing tests focused on gastroenterology, has received New York State approval for the assay as a laboratory-developed test and will be processing the tests and reporting results to physicians. Hanover, New Hampshire-based MiTest was formed out of a research partnership between Dartmouth Hitchcock Medical Center and Cedars-Sinai Medical Center and it developed the test that became CDPath in 2014.
Takeda is selling the assay as an LDT and has no plans to submit the assay for Food and Drug Administration approval or clearance, it said.
CDPath is meant to supplement other tools such as clinical history, colonoscopy, and imaging. Unlike existing blood and fecal tests used to differentiate Crohn's disease from other conditions, CDPath is meant not just to tell patients whether they have the disease but also to help them decide how best to manage it. Dartmouth University medical professor and MiTest Cofounder Corey Siegel, whose research helped develop the CDPath assay, said the interface for test results and analysis helps patients understand their own risks and responses to the disease, helping them make educated decisions about their care. The test, he added, points out which patients are most appropriate for intensive treatment such as with steroids and immunosuppressants.
Siegel, who is also section chief for gastroenterology and hepatology at the Dartmouth Hitchcock Medical Center, recounted two patients who were tested with an earlier version of CDPath as examples of the test's clinical utility. One young man felt healthy and blew off doctors' recommendation to start taking a biologic drug until test results showed he was at high risk of complications within two years.
In another case, the test supported a young woman's decision to manage her mild disease with diet rather than a biologic drug that could harm her performance as a college soccer player. According to Siegel, for years while being tested with CDPath, she had only mild symptoms and occasional prescriptions until her symptoms worsened.
"It was always meant to be a tool that was supposed to be shared between a patient and a provider, as opposed to a blood test that a provider might get back and just say 'It's abnormal,'" he said. "You're meant to show the graph to the patient and really help them make a decision about their treatment."
Siegel was one of the authors of a 2021 article in Crohn's & Colitis that described a significant association between CDPath risk assessment scores and Crohn's disease complications. Among 138 patients in two calibration and validation cohorts, none categorized as low risk had complications within three years, about 30 percent of those considered medium risk had complications, and about 60 percent deemed high risk had complications.
Takeda also plans to cover the costs of the CDPath test, blood sample shipping and, through participating vendors, the blood draw as well. Those vendors are Quest Diagnostics Patient Service Centers, Prometheus-contracted phlebotomy sites, and certain mobile phlebotomy providers.
The costs of the test are limited to patients who have commercial insurance or are uninsured. Patients covered by Medicare, Medicaid, or other federal or state insurance programs are ineligible to participate in the testing program, Takeda said.
In a statement, company officials said they are providing the free tests because they see an urgent need to improve gastroenterological care.
"Offering CDPath at no cost to eligible adult patients provides an opportunity for patients in partnership with their physicians to map out a personal plan for managing their CD," Takeda said.
Siegel said the CDPath test is not a companion diagnostic to any approved or experimental treatment options, nor do the results steer patients toward any particular drug.
Takeda declined to describe any commercialization plans for CDPath outside the US.
A number of other firms are also working on assays for Crohn's disease, including Adaptive Biotechnologies, ProciseDx, and Theradiag.
Cambridge, UK-based firm PredictImmune has also been working to bring its CE-marked Crohn's disease prognostic test to North America. A company spokesperson said that the PredictSURE IBD assay for Crohn's disease and ulcerative colitis will be available through KSL Diagnostics starting in early December.
A systematic review and cost-effectiveness study published in 2021 in Health Technology Assessment examined reports on the performance of PredictSURE IBD and another CE-marked Crohn's prognosis test, Israeli firm Glycominds' IBDX biomarker-based stratification tool. The authors, from the UK's National Institute for Health Research, found limited evidence linking the test results with the need to escalate treatment. None of the studies that met their eligibility criteria reported on the sensitivity or specificity of the IBDX assay, and only one estimated sensitivity, specificity, and negative predictive values for the PredictSURE IBD tool, they wrote.
But the authors noted that those few studies found significant links between results that predict higher risk and the need for treatment escalation.