By Ben Butkus
Gen-Probe is in the early stages of developing a new version of its Panther molecular diagnostics system that will include real-time PCR capabilities on top of the platform's current isothermal amplification technology.
The company said that the new system, which is expected to be launched in 2015, will serve as a platform for real-time PCR-based assays developed through Prodesse, which Gen-Probe acquired in October 2009.
In addition, Gen-Probe continues to develop a real-time version of its isothermal amplification technology, called transcription-mediated amplification, which it plans to use for viral load monitoring assays slated to launch on Panther by 2014.
Gen-Probe President and CEO Carl Hull informed investors of the company's plans last week at the JP Morgan healthcare conference in San Francisco.
Gen-Probe developed Panther to complement its flagship Tigris system for automated molecular diagnostic testing. Whereas the high throughput of Tigris makes it ideal for use in high-volume clinical testing labs, Panther is intended for use in low- to mid-volume labs.
Otherwise, the platforms share many of the same technologies, including a proprietary target capture method based on capture oligomers and magnetic microparticles; and transcription-mediated amplification, an isothermal amplification method that can produce billions of RNA amplicons from a single target molecule in less than one hour.
The company launched Panther in Europe in late 2010. At the time, Michael Watts, Gen-Probe's vice president of investor relations and corporate communications, said that the company had hoped to gain 510(k) approval from the US Food and Drug Administration by the end of 2011 (PCR Insider, 12/2/2010). In May 2011, Gen-Probe filed for such approval (PCR Insider, 5/25/2011).
However, in November, during a conference call discussing the company's Q3 2011 financial results, Hull noted that Panther would likely not be approved before the end of 2011, which had been a best-case scenario. In addition, Hull said Gen-Probe expected the platform to achieve FDA approval in Q1 or Q2 of this year.
Currently, the bulk of Gen-Probe's molecular diagnostic tests, including its portfolio of Procleix blood screening assays and its Aptima HPV and Aptima Combo 2 (for chlamydia and gonorrhea) assays, run on the Tigris and Panther systems in countries recognizing the CE Mark. Gen-Probe also expects to offer many of those assays on the Panther system in the US once it wins FDA approval.
However, when Gen-Probe acquired Prodesse in 2009 for approximately $60 million in cash plus additional potential milestone payments, it did so primarily for Prodesse's collection of molecular tests for respiratory pathogens, including assays for influenza A, influenza B, and respiratory syncytial virus.
Prodesse's assays are based on real-time PCR and Taqman reagent chemistry, and can be used on various nucleic acid extraction and real-time PCR platforms, including Cepheid's SmartCycler II System — but not the Tigris or Panther system, which is one of the reasons GenProbe is adding real-time PCR capabilities to Panther.
"I think we've long recognized that we'd like a proprietary platform for [the Prodesse assays]," Watts told PCR Insider this week. "After doing a fair amount of analysis internally, this made a fair amount of sense to us. So the first … menu for the next-generation [Panther] will in fact be the Prodesse assays."
Watts added that the company is "happy" thus far with the customer feedback it has received about the current version of Panther, but "one of the questions that comes up a lot from customers is: 'I love this instrument, love the automation, love the workflow. What else can you do with it?' Given some technical advancements, one of the things we are now able to do is add those real-time PCR capabilities."
Watts stressed that the real-time PCR capabilities will be a "supplement" to Panther's current TMA technology. "The idea is that we would be able to do both on the same box — TMA assays such as our Aptima Combo 2; HPV; [and] Trichomonas … plus those PCR-based assays."
Gen-Probe has also been developing a real-time version of TMA, which is currently an endpoint assay technology. Watts said that this assay chemistry will prove useful for viral load assays for infectious diseases such as HIV, hepatitis B, and hepatitis C. He added that Gen-Probe is targeting 2014 to launch real-time TMA assays, likely in Europe.
In addition, Gen-Probe spinoff Roka Bioscience is using the TMA technology, among other Gen-Probe-developed innovations, to tackle food safety testing (PCR Insider, 1/28/2010). Roka is also collaborating with Millipore to develop assays for biopharmaceutical contamination testing using real-time TMA in combination with Millipore's sample prep methods, a partnership that Millipore began with Gen-Probe before Roka was formed.
It is worth noting that one of Gen-Probe's major competitors on the molecular diagnostics front, Qiagen, has moved away from isothermal amplification toward real-time PCR. In 2008, Qiagen licensed BioHelix's isothermal helicase-dependent amplification technology with plans to combine it with its hybrid capture 2 technology for various molecular diagnostic tests, including tests for chlamydia and gonorrhea.
However, in May of last year Qiagen said that it was abandoning the isothermal amplification method in favor of real-time PCR-based technology for assays to be run on the next generation of its fully automated QIAensemble molecular testing platform (PCR Insider, 5/12/2011).
In other Gen-Probe news from the JP Morgan conference, Hull said that the real-time PCR-enabled version of Panther was one of two new instrumentation platforms that Gen-Probe is developing. The other is a new instrument to further automate molecular testing from cytology specimens. The company did not provide further details about this platform.
In addition, Hull said that the firm has thus far placed a few dozen Panther systems outside the US since its European launch. He added that Gen-Probe is banking on two tests to help drive revenue growth in 2012 and beyond: its Aptima HPV test, which was cleared by FDA in October for use on the Tigris platform; and its PCA3 test for prostate cancer, which also uses the TMA technology and has been submitted for FDA clearance.
"We've got this new product cycle that's coming out today, which is led by Panther in Europe, hopefully Panther in the US soon with CT/NG; HPV, which just got approved; PCA3, which hopefully is close, and Trichomonas," Watts elaborated this week. "Those should set us up reasonably well for 2012 … and 2013, [with a] full-year effect, looks like it's in pretty good shape as well.
"The idea with some of these new products is to try and drive that next wave of growth," Watts added. "That's really where the TMA-based viral load assays come into play, and also the real-time PCR on Panther."
Have topics you'd like to see covered in PCR Insider? Contact the editor at bbutkus [at] genomeweb [.] com.