NEW YORK (GenomeWeb) — DxTerity Diagnostics has begun commercializing blood sample collection products and a multiplex PCR reagent kit. The Los Angeles-based company displayed its product lines, called DxCollect and DxDirect, at a press event held at the American Association for Clinical Chemistry annual meeting in Chicago last week.
At the event, Bob Terbrueggen, president and CEO of DxTerity, emphasized a unique niche for these products in the new landscape for laboratory-developed testing.
As outlined in a recent report from the Personalized Medicine Coalition and covered in PGx Reporter, new pricing of molecular diagnostics may now constrain recouping of R&D costs, and running a sizeable enough clinical trial to earn a reimbursement code for an LDT is a major cost associated with assay development.
Terbrueggen cited a recent multi-site trial done by Exact Sciences as an example of the high cost of assay validation. The DeeP-C trial of the Cologuard colorectal cancer molecular test enrolled 10,000 patients at 90 centers. The assay ultimately received a positive review from the US Food and Drug Administration, and the company has begun raising funds for commercialization activities, but only after spending millions of dollars on the trial.
These large sample sizes are likely the way of the future. "Code stacking went away in 2013," Terbrueggen said. "Now, 100 to 500 samples are not enough to get a CPT code."
DxTerity's DxCollect and DxDirect assay would instead allow for "sub-$50 molecular testing," he said. "We have been using this chemistry, and now we want to share it with everybody else, to bring genomics into everyday care."
The at-home collection system could help test developers cut down on cost by enabling crowd-sourcing of clinical trails, Terbrueggen suggested. In this scenario, trial participants would be solicited online, and, after obtaining consent and institutional review board approval, they would be mailed collection devices, thus eliminating overhead for phlebotomy and trial staff.
While there are other venipucture and finger-stick products on the market now, Terbrueggen said they are not easy to use. DxTerity's DxCollect evacuated blood collection tubes are similar to traditional tubes, but contain a unique RNA stabilization buffer. The finger-stick collection device, which was displayed at the event, comes in a small box and was designed to be less error-prone than other devices currently on the market. That device also collects sample into the stabilization buffer, making it suitable for shipping without refrigeration and stable for up to two weeks.
According to data provided by DxTerity, in internally conducted studies the DxCollect system showed a 22 percent improvement in RNA integrity number and a 67 percent reduction in sample-to-sample variability after 14 days of room temperature storage when compared to "the leading blood collection method for molecular testing."
DxCollect tubes and collected samples are in turn compatible with the DxDirect kit, which allows test developers to run their own multiplex assays of up to 40 genes using existing lab equipment.
The process works via non-enzymatic chemical ligation adjacent to DNA or RNA regions of interest. Products are captured on magnetic beads using biotinylated capture probes. The method uses universal primers for amplification, and enables simultaneous detection of up to 40 genes in a biosignature.
For the endpoint PCR, DxTerity is partial to capillary electrophoresis, but other detection methods have been successful, Terbrueggen said. However, many clinical labs have CE platforms from first-generation molecular testing, so using this method could make that equipment useful again, he added.
The DxCollect system is intended for researchers who have their own assays, but DxTerity can also be a co-developer for multiplex blood-based biomarker signature testing.
Each multiplex test would ultimately cost less than $50. Terbrueggen compared this to the Corus CAD assay from CardioDx, for example, which gauges the expression level of 23 genes and has a list price of $1,200.
At the event, Terbrueggen also provided an update on DxTerity's radiation toxicity test, which uses the same technology as DxDirect. Since PCR Insider covered that assay late last year, the company has received CLIA certification and CAP accreditation. It intends to move toward a 2015 clinical trial in order to seek US Food and Drug Administration clearance of the assay, Terbrueggen said. The company also continues to work on a rheumatoid arthritis screening and monitoring product, which will employ finger-stick samples processed in its CLIA labs.