NEW YORK (GenomeWeb) — Early-stage molecular diagnostics developer Mesa Tech International has been awarded $1 million from the National Institutes of Health to further develop its low-cost nucleic acid testing device for respiratory disease diagnosis.
The new award is for the first year of a three-year Phase II Small Business Innovation Research grant that could be worth up to $3 million and which Mesa Tech will use to prepare its platform for clinical studies in support of a 510(k) clearance and CLIA waiver application with the US Food and Drug Administration, Hong Cai, company co-founder and principal investigator on the grant, told PCR Insider this week.
"The mission of Mesa Tech is to bring DNA-based molecular testing … out of the research laboratory to point-of-care settings such as the doctor's office, clinics … and eventually over the counter [as] consumer products," Cai said.
Spun out of Los Alamos National Laboratory in the late 2000s, Mesa Tech has thus far leveraged government funding to support the development of its flagship technology, a disposable dipstick-like device about the size of a ball-point pen and capable of detecting and distinguishing multiple influenza-like pathogens from nasal swab samples in less than 60 minutes and with minimal user training.
The company has already garnered some $600,000 in Phase I SBIR funding from the National Institute of Allergy and Infectious Diseases, which helped it complete a proof-of-concept feasibility study for its platform using a small number of clinical influenza samples.
In 2011, when Mesa Tech was awarded the first $300,000 of its Phase I SBIR funds, Cai told PCR Insider that the device would integrate chromatography-based sample prep, lateral flow technology, microheating elements, isothermal amplification, and colorimetric detection.
The technology was expected to be able to conduct a quad-plex assay — influenza A, influenza B, respiratory syncytial virus, and RNaseP as a control — in about 40 minutes. In addition, the company was hoping to be able to power the device with a 9-volt battery, which would add to its point-of-care credentials.
This week Cai said that many of the platform's characteristics remain the same, except for the amplification chemistry. Instead of employing isothermal amplification, Mesa Tech is now using a proprietary "oscillating amplification" scheme.
"It's basically a two-temperature amplification strategy, with the two temperatures [differing] by around 20 degrees [Celsius]," she said. "It is much more efficient in terms of amplification and speed. It actually requires a lot of modifications because it's a huge departure from a traditional PCR design strategy."
Other advantages of this amplification strategy, Cai said, include a much less stringent temperature control scheme and greatly simplified heating/cooling strategy, all of which greatly reduces the system's cost and complexity.
Now, Cai added, "we think we can get sample in, result out in less than 30 minutes, and that includes the lysis, amplification, and detection."
Another key aspect of the device is that its amplification volume is much larger — about 40 µL — than most current microfluidic-based amplification technologies, which typically use sample volumes of 10 µL or less.
"This makes our reaction more sensitive by [using] more crude sample in terms of volume, and makes our reaction more resistant to inhibition," Cai said. "It's just more forgiving in terms of robustness."
From the outset Mesa Tech has been developing a multiplexed test to detect influenza A/B/RSV, but Cai noted that the company is now focusing on only influenza A and B in the near term with the idea that it will be easier to obtain FDA approval and CLIA waiver for this less-complex version of the device. Should it achieve this goal, the company could then add other targets to the respiratory assay or develop tests for other infectious agents in general using the same technology.
As part of its efforts under the Phase II SBIR grant, Mesa Tech also plans to further optimize lyophilized reagents to enable ambient temperature storage of assays, develop stable buffer reagents and capsulation methods, and conduct a performance evaluation of the device on additional clinical samples.
Mesa Tech is also in the process of seeking private funding "to expedite the initial commercialization efforts for the flu A/B studies," Cai said.
This process may be helped by the fact that earlier this year the US Patent and Trademark Office published a pair of patent applications covering Mesa Tech's platform: US Patent Application No. 20140045191, entitled "Integrated device for nucleic acid detection and identification," and No. 20140045221, "Oscillating amplification reaction for nucleic acids."