Swiss molecular diagnostics developer Diagnoplex said last week that it has closed a CHF1.3 million ($1.4 million) financing round led by Debiopharm Diagnostics, part of the Swiss-based global biopharmaceutical conglomerate Debiopharm Group.
Diagnoplex will use the funds to advance its real-time PCR-based blood test for early-stage colon cancer detection through the CE IVD mark process with the hope of making the assay commercially available in Europe as a laboratory-developed test in the first half of 2014, Diagnoplex CEO and Founder Stavros Therianos told PCR Insider this week.
In addition, the company continues to seek funding to perform a prospective multi-center comparison study of its assay, called Colox, and fecal immunochemical testing with the goal of making it eligible for patient reimbursement from insurance companies.
Diagnoplex, based in Lausanne, was founded in 2005 to commercialize molecular diagnostics — with colorectal cancer as an initial target — using single-channel multiplex qRT-PCR technology that Therianos developed while he was a researcher at the University of Rochester.
To achieve this goal, the company in 2008 raised approximately $8.3 million in a Series A financing round led by previous seed funder Novartis Venture Fund and NeoMed, with additional investment from Initiative Capital Romandie.
In 2011 Diagnoplex garnered a Series A financing extension for an undisclosed amount from Debiopharm, which has provided funding to several early-stage molecular diagnostic and biopharma firms over the last several years (PCR Insider, 1/20/2011).
Diagnoplex had planned to use the extension financing to complete a 1,400-patient clinical trial of Colox, which was at that juncture still based on the single-channel multiplex qRT-PCR technology.
This week, in a series of email and telephone interviews with PCR Insider, Therianos disclosed that the company had successfully "locked in" the 29 biomarkers that comprise Colox and had completed both an analytical and clinical validation of the assay, achieving a specificity of 89 percent and sensitivity of 80 percent — not necessarily the most specific or sensitive available molecular assay for colorectal cancer, but "very desirable for a blood-based test," Therianos said.
"We don't position our test for the moment as a screening test," he said. "We are not there yet. We need additional clinical studies, and that's also why we are fundraising." Instead, the company is positioning Colox as an assay to identify individuals at risk for colorectal cancer prior to further evaluation with a colonoscopy.
Therianos also disclosed that the company has left behind the single-channel multiplex qRT-PCR methodology in favor of a tried and true protocol — TaqMan-based qRT-PCR run in parallel on well plates using a Roche LightCycler 480 platform.
The single-channel method involves running "a certain number of PCR cycles with a primer mix containing all the primers of interest — you could go up to around 50 or 60 primer pairs in a single mix," Therianos said. This is followed by a second round of SYBR Green-based PCR, yielding the ability to quantify up to 60 genes simultaneously and analyze multi-gene signatures.
"We developed this methodology in early 2000, at the very beginning of qPCR protocols," Therianos said, and the company used the method to validate a set of more than 100 gene products that had been discovered through next-generation sequencing using either digital gene expression tag profiling or a "candidate gene" approach.
The method is "very convenient to use because it is SYBR Green-based, very flexible, and as a molecular biologist you could learn it in, I think, a half hour," Therianos said. However, the technique is "a little bit too tedious … we never tried to optimize it for high-throughput screening for a product that you want to put on the market. So we used it for the biomarker discovery part" of the company's test development, he added.
Once Diagnoplex settled on its 29-biomarker signature, "we started to talk a lot to medical laboratories to prepare a product that meets their needs. There we saw very quickly, at least in Europe, that about 80 percent of the laboratories are using TaqMan and LightCycler. So we then migrated the assay from the single-channel platform to the TaqMan platform."
Therianos said this was essentially the equivalent of moving from a highly multiplexed qRT-PCR system to a highly parallel multi-gene assay. "It's not a huge deal, because they're both quantitative PCR … and for medical laboratories this is routine," he said. "For us it was really going from a project to a product. As long as you are in project mode — discovery, validation — then you have a big advantage with the single-channel PCR because it is much cheaper than designing and using TaqMan probes. But if you talk about the product … we had neither the time nor the money to fully validate the platform. So we decided it was easier to migrate to the platform [that we currently use]."
The recent financing from Debiopharm will now help Diagnoplex finalize a market-ready version of its Colox LDT. "There is nothing to invent or add, it's just the time necessary to provide information [to regulatory authorities]. It's absolutely not the sexy part of what we're doing, but it has to be done."
In addition, the funding from Debiopharm "is a clear sign from our present investors of their will to support Diagnoplex in the clinical aspects of Colox's development," Therianos said. Other investors participating in the recent funding include Neomed and Initiative Capital Romandie.
Looking beyond a CE-marked Colox, Diagnoplex would like to commercialize its test in the US, first through a CLIA laboratory and eventually by obtaining US Food and Drug Administration approval. This, however, "will necessitate quite a fundraising," Therianos said. "Meanwhile, we would be interested in co-development and outlicensing opportunities in the US, especially."
He added that Diagnoplex has completed some early work on other disease diagnostics. "As you can imagine, following the same design and rationale, we will develop additional tests in the near future in the field of cancer screening," Therianos said. "We already have clear indications about a gene signature for some types of hematological diseases where no screening test is available. Another interesting aspect of the pipeline is to adjust Colox to be used for inflammatory bowel disease patients, who have a higher risk for colorectal cancer, as well as for patient monitoring."