NEW YORK – Microplate Dx recently raised £2.5 million ($3.1 million) in a seed funding round that is expected to enable the Glasgow-based company to meet multiple milestones in coming months, including embarking on clinical feasibility studies of its point-of-care diagnostic platform for antibiotic susceptibility testing and developing its prototype into a commercial product.
CEO Stuart Hannah said in an interview that conducting antibiotic susceptibility testing to guide therapy selection in cases of suspected urinary tract infections (UTIs) will be the "beachhead opportunity" for the Scottish diagnostics firm but added that other applications are envisioned for its point-of-care system, including in respiratory infections, bloodstream infections, and fungal infections.
"It's very versatile in terms of technology," Hannah said. "It can be positioned in a central laboratory, or it can be positioned at the point of care, so that tests can be performed in places like pharmacies or general practitioners' offices."
Hannah has been involved with the development of Microplate Dx's technology since it originated at the University of Strathclyde in Glasgow, where he was a research associate and knowledge exchange fellow for a number of years before embarking on his commercial career, kicked off by a Royal Society of Edinburgh Enterprise Fellowship. According to Hannah, the work underpinning Microplate Dx's platform began in 2018 and was featured in several publications, including one in Biosensors and Bioelectronics in 2019 and another in Biosensors the following year.
Both publications describe the use of a screen-printed electrode modified with an agarose-based hydrogel deposit to monitor bacterial growth using electrochemical impedance spectroscopy and differential pulse voltammetry. Based on the resulting signals, a diagnostic sensor can detect the influence of antibiotics on bacterial growth within about 45 minutes, allowing the selection of the best antibiotic for treatment, the authors maintained in both papers.
Another paper, published in May this year in Biosensors and Bioelectronics, described the use of Microplate Dx's platform to confirm the antibiotic susceptibility of two pathogens, Escherichia coli and Pseudomonas aeruginosa using printed 3D electrodes developed in collaboration with the University of Strathclyde. In general, Hannah, a coauthor on all three papers, said the company has seen sensitivity of about 98 percent within an hour.
In early 2022, Microplate Dx raised an undisclosed pre-seed round that allowed Hannah to leave his position at the University of Strathclyde to become the full-time CEO of Microplate Dx, as well as to secure a licensing agreement with the university around its foundational IP. It also allowed the company to hit various milestones that enabled the follow-on seed round the company announced last week.
According to Microplate Dx Cofounder and Chairperson Poonam Malik, who is also head of investments at the University of Strathclyde, the new seed financing has allowed the company to expand its team by around a quarter. About 14 people are now involved with Microplate Dx in different roles. Malik also noted that the company's initial pre-seed investors, UK-based Deepbridge Capital and the University of Strathclyde, came on board again for the seed round and were joined by new investors Scottish Enterprise, SIS Ventures, and Thairm Bio.
Microplate Dx's goal now is to embark on a clinical feasibility study of its platform for use in therapy selection for UTIs, which "is clinically vital," as patients are often treated with broad spectrum antibiotics first. Meanwhile, if susceptibility testing is performed using culture, it takes several hours to get results, leading to an increase in antimicrobial resistance. About a quarter of sepsis cases begin as UTIs, Hannah maintained, making selecting the best treatment in a rapid manner necessary to reduce burdens on health systems and to save lives.
The planned feasibility studies will be undertaken with external partners, with an eye toward improving its offering ahead of a yet-to-be-determined regulatory submission, perhaps as soon as 2025.
"This will allow us to position the diagnostic in the clinic, providing the chance to understand the performance of the system," said Hannah. "It will be great to be able to start developing that pivotal in situ clinical data and gain valuable feedback on usability and human factors aspects," he said.
In addition to carrying out a study of the technology with partners next year, Microplate Dx will also work to scale its prototype into a minimum viable product, Hannah said, and develop the instrumentation and test cartridges for UTIs. Microplate Dx's website depicts a benchtop platform capable of reading different cartridges using the firm's technology. He noted that the company intends to sell its product in low- and middle-income countries, not just within Europe or the US, which means it must be affordable.
Pricing for the tests or instrument has not yet been determined. Hannah said that Microplate Dx is aiming for cartridge production to be in line with producing diabetes test strips. "We are aligning to the diabetes model, with high volume and high production," he said.
Cost is one reason Microplate Dx might find adoption for its instrument and test cartridge easier when they launch. But, as Hannah said, they are also miniaturizing and quickening the same processes as culture, which means that the approach might be more familiar to potential users. The time-to-result for the platform is currently less than an hour, with 98 percent sensitivity, Hannah commented.
"We are constantly innovating to push the time-to-results as much as possible to be useful at the point-of-care, but we are currently about 50 times faster than current turnaround times for culture-based methods," he said.
Its UTI panel contains all of the major US and European UTI-focused antibiotics, and can be upgraded as needed. "That's the beauty of the test," said Hannah. "We can exchange those for different [therapeutics] for different indications with relative ease."
Malik noted that Microplate Dx's system provides a phenotypic measurement. "The advantage of our system is that we are miniaturizing those agar plates to the tips of these electrodes," she said. "We can provide a confirmed phenotypic measurement output — whether the bacteria is growing or not growing in the presence of a panel of antibiotics — and if it is not growing, then that tells the physician if it's the right antibiotic to use," she said.
If a patient is already resistant to a certain antibiotic, Malik added, then clinicians will also know not to use that one, even if it might have been a routine, first-line antibiotic of choice.
Other companies, employing a variety of approaches, are trying to address the need for rapid antibiotic susceptibility testing for patients suffering from UTIs. Scottsdale, Arizona-based PathogenDx earlier this year discussed plans to offer a microarray-based test that can enable the identification of 26 pathogens and 20 associated antimicrobial resistance genes.
Also in the US, Rockville, Maryland-based OpGen has developed a multiplex PCR-based test called Unyvero for the same indications, which it submitted to the US Food and Drug Administration for de novo classification in May.
In Europe, Hamburg, Germany-based Vela Diagnostics last year introduced a research-use-only multiplex PCR test for UTI diagnosis and AMR resistance that runs on the Thermo Fisher Scientific QuantStudio 5 real-time PCR system.
Hannah acknowledged that there are competitive technologies in the marketplace but noted that some detection methods require more costly platforms. In general, though, the most competitive and generally widely accepted technology remains culture, and the trend underway, initially at least, is not to replace culture entirely but to provide a point-of-care test that can improve the prescription of antibiotics to patients with UTIs upon initial presentation.
"The big push is toward point-of-care testing and trying to speed up this process," he said.
By the end of next year, Microplate Dx hopes to be closer to launching such an offering for clinical use. Its regulatory pathway is not yet clear — changes in the UK and European regulatory systems are ongoing, and the company is keen to engage the FDA, he said.
"We are keeping our regulatory and commercial approach broad for the time being," commented Hannah, "and designing products that can be used across multiple markets, while aligning to US and European requirements."