This article has been updated from a previous version to clarify information related to an agreement GenMark announced earlier this year.
Life Technologies and its Applied Biosystems group have sued GenMark Diagnostics for allegedly infringing a patent owned by Applied Biosystems and related to a multiplex, PCR-based polynucleotide-capture method, according to a court document filed earlier this month.
In the lawsuit, filed with the US District Court for the Southern District of California, Life Tech and Applied Biosystems allege that GenMark has infringed US Patent No. 6,514,699, "Multiplex polynucleotide capture methods and compositions."
The patent, originally awarded in 2003 to Applied Biosystems predecessor PE Corporation, more specifically relates to methods and compositions for "simultaneously generating a plurality of polynucleotide sequencing ladders or PCR amplification products … generated from … an oligonucleotide primer comprising a recovery tag," according to the patent's abstract.
The patent further states that the uniquely tagged sequencing ladders can then be separated from one another by binding to compounds immobilized on a solid support; and then released from the immobilized recovery tag binding compounds and subsequently resolved into individual components. Such methods, according to the patent, may be adapted to separate multiple simultaneously generated polynucleotide amplification products. Lastly, the patent covers kits for performing the described methods.
Life Tech and Applied Biosystems allege in their lawsuit that GenMark has been "infringing, contributing to the infringement of, and/or inducing others to infringe the '699 patent by making, manufacturing, promoting, marketing, distributing, offering for sale, and selling … certain products for nucleic acid analysis," including GenMark's eSensor system, cartridges, and reagents.
The plaintiffs have also alleged that GenMark "knowingly and actively encourages and intends" its customers to practice one or more claims of the '699 patent." As an example, Life Tech and Applied Biosystems claim that GenMark "instructs and provides technical support to customers to use certain eSensor products for multiplex molecular diagnostic tests."
Life Tech and Applied Biosystems did not name specific customers that are using GenMark's technology in molecular diagnostic development. A Life Tech spokesperson said that as policy the company does not comment on ongoing litigation. GenMark officials were not immediately available for comment.
The plaintiffs are seeking judgment from the court that GenMark has infringed the claims of the '699 patent; that it be enjoined from making or selling products that infringe the patent; and that all products currently infringing the patent be destroyed. Life Tech and Applied Biosystems are also seeking monetary damages attributable to infringement of the '699 patent "in an amount according to proof at trial, but not less than a reasonable royalty," the complaint states.
According to GenMark's website, the eSensor method involves extracting DNA from patient samples, amplifying target DNA using PCR, performing an exonuclease reaction to create single-stranded DNA, and performing multiplexed detection and analysis on its XT-8 instrument.
More specifically, analysis on the XT-8 system comprises mixing target DNA with signal probe solution. If the target DNA is present it hybridizes to the signal probes. The solution is then pumped through the microfluidic chamber of a cartridge; and the target DNA/signal probe complex completes the reaction with the pre-assembled capture probe. Finally, voltage is swept across each electrode to electrochemically detect and analyze target DNA.
GenMark, based in Pasadena, Calif., was created in March of this year when its predecessor, London-based Osmetech, filed for an initial public offering of stock in the US under the GenMark name. As part of the transaction, Osmetech reorganized to become a wholly owned subsidiary of GenMark. The company, which raised $27.6 million in its IPO in early June, now trades on the Nasdaq exchange under the symbol "GNMK."
GenMark has been commercializing various molecular diagnostic products utilizing the eSensor technology and XT-8 platform, including a test for warfarin sensitivity.
In September, the company said that the warfarin sensitivity test was selected for use in a clinical trial sponsored by Iverson Genetic Diagnostics and designed to assess the impact of genotype on the occurrence of adverse events during warfarin drug therapy (PCR Insider, 9/30/2010).
However, an Iverson spokesperson told PCR Insider this week that the contract with GenMark has not yet been finalized and the companies are still in discussions. The spokesperson said that the company did not authorize GenMark's announcement of the agreement in September.
The XT-8 platform was also selected for use last year in the Clarification of Optimal Anticoagulation through Genetics Trial, a warfarin sensitivity clinical trial sponsored by the National Heart, Lung, and Blood Institute of the National Institutes of Health.
GenMark predecessor Osmetech received 510(k) clearance for the eSensor warfarin test and XT-8 platform in 2008. The company also has a cystic fibrosis genotyping test cleared for US marketing; has developed a respiratory viral panel test and a thrombosis risk test, both of which are labeled for investigational use only; and has a pipeline of eight potential products in development or design, including a Plavix sensitivity test and a KRAS mutation test.