Molecular diagnostics company Diagnovus this week launched a real-time PCR-based assay to measure a patient's risk of developing a specific type of esophageal cancer from the condition Barrett's esophagus.
The test, called Engauge GI-Barrett's Esophagus, uses real-time PCR performed on Life Technologies' ViiA 7 system to measure methylation of eight biomarkers in biopsied tissue from Barrett's esophagus patients to determine their risk of progression to high-grade dysplasia or esophageal adenocarcinoma.
According to the company, Engauge GI-Barrett's Esophagus is the first genomic assay to aid physicians in predicting this risk of progression, and may improve the current standard of care for Barrett's esophagus patients, which includes endoscopic surveillance or treating for gastroesophageal reflux disease.
Founded in 2011, Diagnovus now has three genomics-based diagnostic products, with more in development, all of which use the brand name Engauge, James Stover, vice president of business development at the company, told PCR Insider. Diagnovus also currently offers Engauge-Cancer-DLBCL Risk Score and Gene Panel, tests designed to aid physicians in calculating risk and tailoring treatments, respectively, for patients with diffuse large B-cell lymphoma.
The company offers all of its tests through its CLIA-certified lab in Nashville, Tenn., which is equipped with a number of Life Tech products. This includes the ViiA 7 system, which Life Tech introduced in 2010 as the successor to its ABI 7900HT Fast real-time PCR system.
The ViiA 7 has a touch screen, programmable "one-button" protocols, and does not require a separate computer, according to product information available through Life Tech's website. It also has what Life Tech calls "the optiflex system" — six sets of emission and excitation filters that rotate independently to maximize multiplexing. With ViiA 7, it's also possible to remotely access and monitor progress of experiments as they are running.
While all of Diagnovus' tests thus far have been CLIA LDTs, Stover says the company is engaged in discussions with the US Food and Drug Administration regarding next steps and potential regulation of the assays. "We're prepared to submit to the FDA if it's needed," he said.
Steven Meltzer, a researcher at Johns Hopkins University School of Medicine, developed Engauge GI-Barrett's Esophagus. Diagnovus has a license to the technology from Johns Hopkins through an agreement with intellectual property brokerage MPEG LA.
The assay requires seven slides, or two 20-micron-thick slices from formalin-fixed paraffin-embedded biopsy tissue. It then measures the expression and methylation profile of eight genes in that tissue using a unique software algorithm, Stover said. According to a patent application describing the test, those genes include HPP1, p16, RUNX3, CDH13, TAC1, NELL1, AKAP12, and SST, as well as a control gene. Methylation of these genes in esophagus biopsies was previously correlated with progression to cancer.
For example, according to the patent application, the CDH13 gene encodes a cadherin and is a known tumor suppressor gene. Hypermethylation of the promoter region of this gene blocks transcription, thus depleting this important cancer-blocking mechanism in affected cells. This hypermethlyation is correlated with progression from Barrett's esophagus to adenocarcinoma.
However, not all Barrett's patients go on to develop cancer, so how to monitor them has been controversial.
Engauge GI-Barrett's Esophagus is designed to reduce the risk of false positives and needless endoscopies by stratifying patients into risk categories and predicting "whether the patient is what we call a progressor or a non-progressor," Stover said, or whether they are at higher risk of developing adenocarcinoma. Physicians can then schedule less frequent monitoring for those unlikely to develop cancer, while more closely monitoring a patient whose genetic signature is a red flag for cancer with a high fatality rate.
Previously, Barrett's esophagus patients needed to have frequent endoscopies and biopsies to make sure they weren't developing cancer. According to a presentation available on the website for Meltzer's lab — the Gastroenterology Early Detection Biomarkers Laboratory at JHU School of Medicine — sorting patients into high and low risk with Diagnovus' assay could reduce the number of endoscopies by almost 60 percent, which could translate to an annual savings of $186 million. He also predicted that early detections will add a savings of $108 million, and that this nearly $300 million in annual savings should motivate insurance companies to reimburse for the test.
Diagnovus is introducing Engauge GI-Barrett's Esophagus to potential customers at the American College of Gastroenterology meeting next week in San Diego.