This article was originally published on Nov. 15.
PHOENIX, Ariz. — Luminex this week unveiled its cartridge-based, sample-to-answer molecular diagnostics platform and revealed its initial planned in vitro diagnostic test menu for the new system.
Specifically, Luminex hopes to commercially launch assays for Clostridium difficile, herpes simplex virus I and II, and combined influenza A/influenza B/respiratory syncytial virus in Europe in the second half of 2014 and in the US, assuming regulatory clearance, in early 2015.
The system, which will also enable users to create laboratory-developed tests using their own analyte-specific reagents or those sold by Luminex, is expected to serve as a higher throughput and more focused complement to Luminex's existing respiratory and gastrointestinal pathogen panels running on its relatively lower throughout but more highly multiplexed xTag assays and xMap platform.
Luminex CEO Patrick Balthrop introduced the new system — previously dubbed Project Aries and still without an alternative brand name — at the Association for Molecular Pathology annual meeting held here this week.
Balthrop first disclosed the company's plans to develop the system in an interview with PCR Insider nearly a year ago preceding the company's investor day meeting in New York. In terms of core assay technology, the platform was to combine real-time PCR chemistry obtained as part of Luminex's acquisition of EraGen Biosciences last year with the sample-to-answer molecular testing instrument it acquired along with startup GenturaDx in the summer of 2012.
Luminex has since packed these technologies into a single platform with a number of bells and whistles that the company identified as important after engaging in extensive discussions with the molecular pathology and clinical diagnostics community, Balthrop noted during the unveiling. The system is not yet commercially available, but the AMP unveiling marks the beginning of a beta-testing stage through which the company will make the system available to select early-access users.
The platform, which sits on a laboratory bench, is taller than it is wide or deep due to the fact that it essentially contains two testing models stacked together with an integrated touchscreen PC, which obviates the need for a separate computer running analysis software.
Each of the two testing modules in a given instrument accepts a magazine that can be loaded with six test cartridges. With random batch access, this means the instrument can run up to 12 different (or the same) test cartridges simultaneously with 1.5- to 2-hour turnaround time from sample to answer. As such, Balthrop noted, 48 test cassettes can be run on a single instrument in one eight-hour shift.
The platform also contains barcode scanning for test chain of custody, and several instruments can be linked together on one benchtop to further increase throughput.
Luminex will offer two versions of the test cartridge. The first will contain pre-loaded lyophylized reagents from Luminex that are appropriate for the IVD test being offered. The second version will be able to accept a laboratory tube that users can load with their own analyte-specific reagents and master mix for a laboratory-developed test.
Both versions of the cartridge will feature Luminex's proprietary sample prep capabilities, which will allow tests to be run from a number of raw sample types.
Following the official unveiling, Jeremy Bridge-Cook, Luminex's senior vice president of R&D, provided PCR Insider with additional information about this sample prep technology, as well as other additional details about the platform.
The cartridges use existing, proven sample prep chemistry "but the way the sample moves through the cassette is proprietary and patented," Bridge-Cook said.
So far Luminex has successfully used the sample prep technology on whole blood, stool, nasopharyngeal swabs, and universal or other types of transport medium, including Cary-Blair. Bridge-Cook said that the company has not yet tested urine or buccal swabs, but expects these to be compatible.
At the heart of the new platform is Luminex's MultiCode chemistry, which originated with EraGen. These reagents feature synthetic base pair chemistry for probe-free, real-time PCR and highly specific and sensitive detection and quantification of nucleic acid targets.
In comparison, in a Luminex xTAG assay, PCR products undergo an allele-specific primer extension step. The 5' end of the primers are then attached to an xTAG universal tag sequence that is hybridized to the complementary anti-tag sequence coupled to xMAP beads, which are subsequently read and analyzed on the firm's Luminex 100/200 and Magpix instruments.
The key feature of xTAG assays is their high degree of multiplexing, and Luminex currently sells a US Food and Drug Administration-approved Respiratory Virus Panel and Gastrointestinal Pathogen Panel based on these assays. But while xTag panels are targeted more towards larger core clinical labs, the firm believes Aries is ideal for labs requiring higher throughput but not necessarily needing a high degree of multiplexing.
"Most customers want to run both depending on what kind of patient we're talking about," Bridge-Cook said. "We're talking about running comprehensive panels on some patients and more focused assays for others."
Two of Luminex's first three planned in vitro diagnostic assays — C. diff and Flu A/B/RSV — are currently covered by the GI and respiratory virus panel, respectively. Luminex is also developing Aries assays for two as-of-yet undisclosed infectious diseases targets, slated to be commercialized around the same time as the three disclosed assays.
Before Luminex markets IVD assays, however, early-access users will be able to use the platform to develop their own tests using analyte-specific reagents. This feature sets the Aries platform apart from most sample-to-answer MDx platforms currently on the market, save Becton Dickinson's BD Max, which has an LDT mode.
However, "unlike the BD Max, with [our platform], once an LDT cassette is manufactured, you can use it just as easily as with an IVD," Bridge-Cook said. A lab can hire "hard-to-find … skilled scientists to make the assays in bulk, but then those assays can be run by relatively unskilled workers … with a workflow that is just as easy and bulletproof as an actual IVD assay," he added.
BD's Diagnostics unit has a partnership in place with several assay developers to create new diagnostic assays for use on the BD Max, and Luminex is considering employing a similar strategy, Bridge-Cook said. However, he noted that Luminex already offers a line of MultiCode ASRs, which it could supply to users for test development.
Bridge-Cook declined to disclose pricing for the new system or test cartridges.