Sometimes molecular diagnostics doesn’t have to involve highly complex assays or sophisticated instrumentation.
Timothy Stenzel, M.D., Ph.D., CSO of Quidel, discussed his company’s collaboration with BioHelix to develop isothermal amplification tests using the latter’s helicase-dependent amplification (HDA).
With this technology, designed for resource-poor areas in the developing world, or simply where capital expense budgets are low or being slashed (even in the U.S.), “you don’t need a thermocycler, just a heat block,” he says.
“I think there are untapped markets out there,” Dr. Stenzel confided. “It’s our understanding that there are nonmolecular labs that can’t afford to get into molecular diagnostics, because they either can’t afford to hire the personnel, set up a high-complexity lab, or buy the current integrated systems right now. If there were a lower cost option where they didn’t have to make a capital outlay, they would get into molecular now.”
In the developing world, right now molecular testing is a challenge. And because it’s mainly done in centralized locations, the turnaround to get results back to patients can be months, and many patients are lost to follow-up as a result.
The Quidel-BioHelix system makes use of capillary flow on nitrocellulose membranes, similar to that of over-the-counter home pregnancy tests. It’s easy to use, high performing, and uses a visual read: you see a line develop and the target is there; you don’t see a line and it’s not there. Because this type of technology is less prone to inhibition, it’s often not necessary to perform an up-front nucleic acid extraction (or to make the large capital expense for an extractor).
Another attractive thing is that the technology can be multiplexed—even allowing for an internal control to be placed in the same tube with the target—he noted, but it won’t be as highly multiplexed as arrays.
The first menu is in the area of infectious disease, offering up some fairly obvious targets that labs are expecting, Dr. Stenzel said. One of the top priority targets is C. difficile testing, especially in U.S. where it is an important pathogen for hospitals to get control of. “The whole area of hospital-acquired infections is still growing and is very interesting.”
Dr. Stenzel predicts that much of the C. difficile testing currently being done by EIA “will move to molecular as soon as labs can get up and going with a method that works for them.”
MDx in ROW
Cepheid is collaborating with the Foundation for Innovative Diagnostics to bring molecular diagnostic capabilities to those parts of the world where most of the tuberculosis deaths are occurring—the high burden developing countries (HBDCs).
“With our Cepheid Cares program, we have partnered with key nonprofit organizations to provide special programs and pricing to the HBDC’s where it is needed most,” says Russel Enns, Ph.D., the company’s senior vp and chief regulatory officer. The automated MTB/RIF test allows for detection of Mycobacterium tuberculosis and resistance to rifampin using Cepheid’s GeneXpert platform. The only manual step for this assay is mixing sputum with buffer before transferring it to a consumable plastic cartridge.
Diagnosing tuberculosis using traditional culture techniques can take one or two months, and finding a drug resistance pattern may take a few more weeks beyond that, while the PCR-based MTB/RIF test can give an answer within a couple of hours.
“The difference is that kids can be kept at the clinic to make sure they get the drugs down, or sent home from the clinic with the right treatment,” Dr. Enns explains.
China on the Move
Some countries that are lumped into the category of the developing world in in vitro diagnostics may catch up with the U.S. and Europe more quickly than we think.
Min Cui, Ph.D., investment partner at Bay City Capital, talked about market opportunities and characteristics for investment in China. He sees the world’s second largest economy as still in its infancy in terms of molecular diagnostics and point-of-care diagnostics.
Yet “because it’s in its infant stage, you’re going to see explosive growth in this area—China will pick up very quickly,” he predicts.
When it does, China will probably go to the best technology available. For example, “you’re going to see next-generation sequencing technology applied to diagnostics in China probably as early as the U.S. adopts it. There’s a tremendous opportunity in my view,” Dr. Cui says.
Similarly, he thinks fully integrated, fully automatic PCR systems and other new technologies are likely to be adopted very quickly in China: “It will probably take a couple of years.”
Because medical products operate in a “highly regulated space,” in which SFDA approval is needed, IP protection in China in the medical product space is far better than its maligned reputation, he notes. As with doing business anywhere, you have to choose a good partner, and do your homework.