By Ben Butkus
Diagnostics firm Quidel is developing an automated "sample-to-result" molecular diagnostic testing platform in collaboration with scientists from Northwestern University and the Northwestern Global Health Foundation, PCR Insider has learned.
Quidel expects the platform, dubbed "Project Wildcat," to be ready for the market by 2014, with initial applications in point-of-care HIV testing in remote and resource-poor areas of the world. Longer term, Quidel sees the platform being used for decentralized molecular testing in more developed countries, according to company officials.
The project also represents Quidel's latest push into the molecular diagnostics market after having built its business primarily on immunoassay testing.
Quidel initially disclosed Project Wildcat during an investor conference call following the October release of the company's third-quarter 2010 financial results. During that call, President and CEO Doug Bryant noted that Quidel had entered into an "exclusive licensing and joint development agreement" with NWU and NGHF to develop the automated testing platform, which was to incorporate clinical sample preparation, nucleic acid extraction, amplification, and detection.
At the time, Bryant also disclosed the expected product launch date of 2014, and said that the company was "excited about the commercialization of a lower-cost integrated system" and the benefits that it would bring to clinical labs.
In February, Quidel reiterated that the project was progressing as planned in a statement accompanying its Q4 financial results; and this week, company officials disclosed even more information about Project Wildcat during a company analyst day in Boston, noting that the platform would be capable of performing eight to 12 fully automated, random-access tests, from sample preparation to result, in about an hour's time. In addition, officials said during their presentation that the platform would incorporate a novel nucleic acid extraction method.
Last week, Kunel Sur, a senior manager at Quidel Molecular, further discussed this extraction method, along with additional details on the testing platform, during a presentation at the Knowledge Foundation's Sample Prep 2011 meeting, held in San Diego.
Specifically, Sur said that the sample preparation system is based on immiscible phase filtration technology, a concept that he and colleagues from Northwestern introduced in a research paper published in September in the Journal of Molecular Diagnostics.
Sur's presentation at Sample Prep 2011 highlighted the idea that in order to successfully implement molecular diagnostic testing in underdeveloped regions of the world, as well as decentralized settings such as schools or drug stores in more developed nations, the platform must be inexpensive, feature a fast time to result, and have low complexity, improved workflow, and lower cross-contamination risk than currently available systems.
One of the biggest hurdles to creating such testing platforms, Sur said, is the sample prep component, which currently typically comprises multiple complex steps and necessitates expensive equipment and high consumable usage.
Immiscible phase filtration addresses many of these issues by using liquid wax "valves," or oil-water interfaces, combined with paramagnetic particles, to remove multiple wash steps. IPF requires only two aqueous solutions: a lysis buffer, where nucleic acids are captured on the paramagnetic particles; and an elution buffer, where they are released for amplification. The magnetic particle-bound nucleic acids are magnetically transported through the liquid-wax valve connecting the lysis chamber to the elution chamber in a specially designed cartridge.
In an integrated sample-to-result device, the elution chambers would double as the PCR chamber, after the paramagnetic particles are simply removed from solution, Sur said.
Advantages of the IPF sample prep method include the fact that it eliminates PCR inhibitors, is relatively fast, operates in an enclosed system to prevent further contamination, and is amenable to automation. Sur also said that the method could be used to purify proteins and immunoassays.
Quidel has not yet disclosed information regarding the amplification and detection components of its integrated platform. However, Sur presented data from in-house testing that demonstrated the system's ability to detect HIV viral RNA from plasma; HIV pro-viral DNA from whole blood in combination with sonication techniques; and chlamydia and gonorrhea from urine samples.
Sur said that Quidel expected the new platform to have an immediate impact in the area of remote HIV viral load testing, particularly in Africa; but that it would also be useful for testing for HIV and other sexually transmitted diseases, including chlamydia and gonorrhea, in developed nations.
Project Wildcat is the most recent step for San Diego-based Quidel into molecular diagnostics market after having previously been known mostly for its QuickVue immunoassay testing kits for a variety of infectious diseases.
In 2009, Quidel inked an agreement with Beverly, Mass.-based BioHelix to jointly develop and commercialize in vitro molecular diagnostic tests for infectious pathogens in a non-instrumented, handheld format combining BioHelix's isothermal helicase-dependent amplification technology and disposable cartridges.
Quidel and BioHelix currently have non-instrumented tests in development for Clostridium difficile, methicillin-resistant Staphylococcus aureus, group B Streptococcus, meningitis, and tuberculosis, among others, the company noted during its analyst day presentation this week.
In addition, the company has initiated what it calls "Project Open Box," a push to develop molecular testing kits for infectious diseases for use on existing molecular testing platforms such as Life Technologies' ABI 7500 Fast Dx and Cepheid's SmartCycler.
Bryant said during the company's Q3 conference call in October that the company was "slightly ahead" of its internal schedule for Project Open Box, and at the analyst day presentation this week, Quidel presented pre-clinical data on its Open Box tests for influenza A/B, human metapneumovirus, and respiratory syncytial virus. Clinical trials for these tests are scheduled to begin in the first half of this year, according to the company.
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