NEW YORK – A point-of-care host immune-response assay from Lumos Diagnostics has potential to contribute to antimicrobial stewardship initiatives associated with respiratory conditions while providing substantial savings for health systems, according to a recent study.
Authors of the study, published recently in the Journal of Medical Economics, reported that health systems may see "substantial cost savings" by applying the test in outpatient settings.
The two-biomarker immunoassay, FebriDx, has been used most frequently by clinicians to help guide their antibiotic prescription decision-making, Robert Sambursky, president and CEO of Lumos, said in an interview.
He also noted that Lumos has seen increasing use of the immunoassay for COVID-19 testing.
The Sarasota, Florida-based company acquired the test when it merged with RPS Diagnostics, its developer, a year ago.
Using a fingerstick of blood and providing results in 10 minutes, FebriDx is a single-use disposable test that consists of a built-in lancet to pierce the skin, a built-in blood collection and transfer tube, and push-button activation.
The test identifies patients who have "clinically significant" infections and can quickly determine whether the condition is viral or bacterial by combining Myxovirus resistance protein A (MxA) and C-reactive protein (CRP), Lumos said.
An elevated CRP without an associated elevated MxA is interpreted as a bacterial infection while an elevated MxA, regardless of CRP level, is interpreted as a viral infection. Tests showing no elevated CRP or MxA are interpreted as negative.
In the JME study, the researchers concluded that adding point-of-care testing to triage patients with acute respiratory infections in outpatient settings can reduce unnecessary antibiotics and antibiotic-related adverse events.
The fear of missing a serious infection frequently causes physicians to prescribe antibiotics unnecessarily, behavior that was the genesis for the JME study, said John Schneider, CEO of Morristown, New Jersey-based Avalon Health Economics, who was an author of the study, along with colleagues at the University of Geneva and Foundation for Innovative New Diagnostics (FIND).
The authors "found that by guiding care using the point-of-care test to differentiate infections, you could save the UK health system £90 million ($110.7 million) per year," Schneider said.
That figure doesn't even include costs associated with antimicrobial resistance, "which are substantial and very difficult to calculate," he said. Potential savings are several times higher for the overall US health system given that far more tests are completed domestically for respiratory and other infections, Schneider added.
The JME study follows earlier research published in 2018 in the Journal of Clinical Medicine. Looking at 205 patients, that study found that the FebriDx assay demonstrated a 97 percent negative predictive value for bacterial infection and 95 percent negative predictive value for viral infection.
The immunoassay "may help to identify clinically significant immune responses associated with bacterial and viral [upper respiratory infections] that are more likely to require clinical management or therapeutic intervention, and has potential to assist with antibiotic stewardship," the study investigators said.
"Studies have repeatedly shown that bacterial and viral infections are difficult to differentiate, with a high rate of inappropriate antibiotics prescribed for likely viral infections, and more rare but serious missed bacterial infections progressing to sepsis," Timothy Sweeney, CEO and cofounder Burlingame, California-based Inflammatix, said in an interview.
Inflammatix is developing HostDx Sepsis and HostDx Fever tests that use proprietary machine-learning algorithms and incorporate the expression of multiple immune genes to identify the presence of bacterial or viral infections and to determine if a patient has or is likely to develop sepsis.
"Especially in the outpatient primary-care setting, where FebriDx and our outpatient-focused HostDx-Fever test [are targeted], guidelines generally recommend against pathogen testing," Sweeney said.
Host-immune response tests have an advantage over molecular tests that look to identify specific pathogens, he said, adding, that pathogen panels are expensive for use in outpatient settings and "can often miss bacterial infections."
Host immune-response testing, on the other hand, can be "fast, cost-effective, and can quickly separate bacterial from viral infections, which is typically enough to allow appropriate treatment," Sweeney said.
Segueing to coronavirus
Recently, Lumos has also found that FebriDx can be used to help determine whether an individual has been exposed to the coronavirus. Though it is non-specific for SARS-CoV-2, the virus that causes COVID-19, the test quickly detects the body’s immune response to SARS-CoV-2 or any other type of respiratory virus, which is advantageous in the context of COVID-19 testing, allowing for rapid triaging of symptomatic patients, Sambursky said.
In a study pending publication and involving 35 patients for SARS-CoV-2 in the UK, FebriDx has shown 100 percent sensitivity in identifying viral infections for patients who were confirmed as being COVID-19 positive, Sambursky said. Those patients were quickly referred to molecular testing specific to SARS-CoV-2, he noted.
As more work is being done to determine FebriDx's clinical utility for SARS-CoV-2 detection, Lumos is "in the midst" of conducting a pivotal clinical trial that serves as a basis for submission for 510(k) clearance with the US Food and Drug Administration, Sambursky said. He declined to provide an anticipated timeline for submitting an application, citing an uncertain regulatory environment because of the COVID-19 pandemic.
Lumos launched the point-of-care immunoassay in European countries in April 2019 after receiving updated CE marking and transitioning to use of an all-in-one cassette.
In February, Lumos announced the closing of $15 million in Series A funding from Australian healthcare innovation and commercialization firm Planet Innovation. The company said it is using the funding for international commercial expansion of FebriDx, the pivotal clinical trial, and other development and manufacturing resources.
Prior to its merger with RPS in May 2019, Lumos main business centered on engaging in contract development and manufacturing projects with diagnostics industry customers, said Sambursky, who had been president and CEO of RPS.
On the contract development and manufacturing side of the business, the company continues to develop and provide manufacturing services for custom, point-of-care diagnostic tests for third parties, including tests for patients suspected of having COVID-19.
The combined company has also been able to leverage knowledge obtained through the contract development and manufacturing services business to provide "cost-efficient, branded products to the market like FebriDx," Sambursky said.
FebriDx is the first assay in a pipeline of future Lumos-branded products, he said. The company is working on a next generation of the test that incorporates a reader that allows semi-quantitation, he said. Technology for the reader had been developed by Lumos prior to the merger.
Overall, the company uses a combination of direct and distributor sales to market its products. A team of commercial managers in the UK and the Netherlands administer its network of international distributors. "The level of interest in the product has grown dramatically as diagnostics in general have become a major topic and focus in the news," Sambursky said.
When it comes to host-response biomarker tools, market education is clearly needed to show providers why tests like FebriDx, HostDx Sepsis, and HostDx Fever are "superior to clinical judgement alone," Inflammatix's Sweeney said. "Every piece of literature confirming the power of the host response gets us closer to our goal of widespread adoption."