LexaGene Launches EUA Tests for Microfluidic PCR Device in Point-of-Care Facilities
LexaGene has begun a series of studies aimed to bring its MiQLab from research-only use to point-of-care use to detect the SARS-CoV-2 virus. Emergency use authorization (EUA) would add a rapid test with the accuracy of polymerase chain reaction (PCR). It is designed for use by the 193,000 CLIA-certified labs in hospitals and clinics throughout the U.S.
“The key for point of care systems is ease of use, but PCR is complicated by nature,” LexaGene CEO Jack Regan, Ph.D., pointed out. “It is vendors’ responsibilities to make it easy regardless of the training of the operator.”
The MiQLab does that. MiQLab is a PCR-based system coupled with microfluidics. Because it is open access, it can be quickly configured to detect emerging variants of the virus.
Users need only to “transfer a collected nasal swab sample into a MiQLab cassette, which is then inserted into the system, and then use the touch screen monitor to initiate sample processing. It takes less than a minute,” he told BioSpace. Results are available in a little over an hour – notably faster than the days often required for reference labs to return PCR results.
One of the key features is built-in sample preparation, which purifies the genetic material from the sample. Many of the rapid diagnostic kits designed for COVID-19 skip sample prep, he said, “but it improves the quality of the data. We’re not trying to compete based on speed only. Antigen-based tests have a high degree of false negatives.” LexaGene offers an alternative.
Obtaining FDA Emergency Use Authorization for a point-of-care setting is complicated and time-consuming, especially for a novel technology like the MiQLab System. To help speed FDA evaluation, Regan said, “We’re using the CDC’s SARS-CoV-2 diagnostic test, automated on our system. That test is validated for use in reference labs. We want to ensure the FDA is comfortable with our automated system, and this removes one question mark.”
“The FDA is prioritizing point of care diagnostics, so we made the decision in December to address this market,” even though the bar for acceptance is higher than for diagnostics going into highly complex labs (reference labs).
For LexaGene, that means completing additional studies and showing that results are consistent regardless of the level of training of the technician running the tests. Data from limit-of-detection tests and specificity against near-neighbor pathogen will be generated this month.
With COVID-19 hospitalizations increasing and two new strains of SARS-CoV-2 circulating in the U.S., “the places we need to get into are swamped.” None-the-less, Regan expects the studies to be completed and delivered to the FDA within a few months.
Although LexaGene is initially applying to the FDA specifically for SARS-CoV-2, MiQLab has the capability to detect up to 27 pathogen that cause flu-like symptoms. Therefore, it can differentiate among strains of SARS-CoV-2 virus and also determine whether a patient has influenza A or B, RSV, or some other virus rather than COVID-19.
That flexibility could become particularly important as the SARS-CoV-2 virus mutates.
“The surface proteins on the UK and South African strains are different from the proteins of the initial strain,” Regan pointed out. “The CDC test is designed to recognize a conserved region of the SARS-CoV-2 genome."
Therefore, it can differentiate SARS-CoV-2 from other viruses, but the CDC test is not designed to identify which of the many different strains of this virus is present. To do that, LexaGene must add assays (tests) that target the specific mutations on the virus’s spike protein that are unique to each strain to be identified.
The microfluidics portion of the MiQLab system contains nine fluidics chambers, each of which can perform three tests. For example, Regan said, “One chamber can look for the common SARS-CoV-2 strain, another can test for specific spike protein mutations, and another for other viruses that cause similar symptoms, such as influenza.”
“If the U.K. or South African strains become important, the CDC will develop tests for those variants,” he predicted. “We would put them on our system. Right now, we don’t have the reference material for sensitivity testing for those strains.”
With the appropriately designed new tests, it is easy to detect variants that are poor matches to vaccines or that are resistant to any developed therapies – a critical step in helping end this pandemic.
“A big problem today is that most tests look for a single pathogen, but there are about 20 different viruses that cause influenza-like illnesses,” he continued. “Clinicians and patients are frustrated by negative results from COVID-only tests, which happen frequently and don’t conclusively rule out coronavirus. A much better solution is to simultaneously look for the other pathogens that cause similar systems and any positive for a virus that isn’t coronavirus is very informative and comforting.
“Because the MiQLab uses microfluidics, it’s easy to add new tests to identify new strains. Our goal is to receive an EUA for COVID-19 diagnosis, and then return to the FDA with a full respiratory panel.
The device currently is being sold into non-regulated markets, such as veterinary diagnostics and for research use by drug developers.
Because the FDA and Health Canada requirements are quite similar, LexaGene plans to also apply for use in Canada before eventually approaching the EMA for a CE mark.