Posted 24 September 2015
By Zachary Brennan
Pathway Genomics is currently marketing an unapproved screening tool, which the US Food and Drug Administration (FDA) believes to be a medical device, for the early detection of up to 10 different cancer types, the agency said in a letter to the company this week.
FDA says that the non-invasive blood test, known as CancerIntercept Detect, "appears to meet the definition of a device" as the company ships blood collection tubes, a medical device, for use with the tool.
"We have also examined published literature and have not found any published evidence that this test or any similar test has been clinically validated as a screening tool for early detection of cancer in high risk individuals," James Woods, FDA Deputy Director for the Patient Safety and Product Quality Office of In Vitro Diagnostics and Radiological Health, said in the letter.
FDA also reviewed a white paper posted by the company on its website earlier this month and the agency said it's "unclear how the literature that you cited, addressing the presence of circulating tumor DNA (ctDNA) in already-diagnosed patients, is adequate to support the expansive claims of screening for early cancer detection using ctDNA in undiagnosed patients for up to 10 different cancers."
The company said on its website that the test, which costs between $299 and $699, depending on how it's purchased, is the "first liquid biopsy designed to detect tumor DNA in high-risk but otherwise healthy patients."
The test works by detecting the "presence of specific genomic markers found" in ctDNA "at levels as low as two copies of mutant DNA per patient plasma sample," and "delivers results in just 2 to 3 weeks," the company says.
Ardy Arianpour, Chief Commercial Officer of Pathway, told RAPS in an emailed statement that the company is carefully considering FDA's concerns and will be responding to the letter.
"We assure that there is physician involvement in the ordering, review and follow-up of CancerIntercept testing," Arianpour said, noting the company believes the tool is a "laboratory developed test [LDT] and, as a CLIA [Clinical Laboratory Improvement Amendments] and CAP [Certified Authorization Professional] certified clinical laboratory, we are offering it as such."
LDTs currently do not need to be approved by FDA, though this letter could raise further questions about FDA's plan to regulate LDTs as medical devices. A legal analysis from January said FDA's plan lacks justification, and there's been other criticism that moving LDTs under FDA's purview could stifle innovation.
Arianpour also took issue with FDA's claim that the test is a direct-to-consumer type model, saying Pathway is educating and marketing the tests to physicians and consumers.
"We believe we have performed appropriate validation of the test as a laboratory developed test, and we are in the process of performing additional studies," he added.