NEW YORK – In the midst of the coronavirus pandemic, diagnostics companies have been frantically developing new tests for SARS-CoV-2. This week Iceni Diagnostics threw its hat in the ring, pledging to deliver a rapid, point-of-care test that could differentiate the virus from more common strains of influenza using artificial glycan receptors.
Based in Norwich, UK, Iceni is focused on developing carbohydrate-based therapeutics and point-of-care diagnostics for infectious diseases. The six-year-old firm's core technology was developed by scientists at the adjacent University of East Anglia. It currently employs 11 people.
Iceni has worked to develop lateral flow assays for flu and other diseases based on its technology and is now developing an assay for SARS-CoV-2, according to Berwyn Clarke, its chairman.
The firm’s approach relies on reading the sequence of sugars on the virus and could enable a yes-or-no home diagnostic kit that could produce an answer within 20 minutes. This might be an attractive alternative to the real-time PCR assays that are currently being used to test patients.
"A lateral flow device is inexpensive, simple to use, and can produce a result in 15 minutes with little or no sample processing," said Clarke. "Being based on glycan molecules, the virus is unable to mutate and avoid surveillance," he said. "The device will not be subject to any recurrent disease outbreak issues or seasonal variation that may occur," he added, "unlike protein and nucleic acid-based tests."
Much of the early work on Iceni's technology was undertaken in the early 2010s by CEO Rob Field, a project leader at the John Innes Centre in Norwich, and CSO David Russell, a professor of chemistry at the University of East Anglia. The investigators published a foundational paper in Organic & Biomolecular Chemistry in 2013 that detailed the development of a plasmonic bioassay capable of detecting human influenza virus and distinguishing it from avian flu using functionalized glyconanoparticles.
Since its founding, Iceni has worked to parlay the technology into multiple assays targeting norovirus, as well as different types of influenza, such as equine flu, which is the most advanced test and is in beta testing.
"The current focus is on point-of-care applications for these glycans, where the technology is working well in early validation," commented Clarke. He noted that the firm does not have a technology platform itself, but rather is capable of "producing scalable quantities of glycan-ligands that can be used in multiple platforms."
The company is now using this expertise to develop a new test for SARS-CoV-2. Clarke said the new project has completed its design phase and will be rolled into a prototype assay within Iceni's influenza portfolio. "The likely time to prototype is six months," Clarke noted, "but it could be accelerated for emergency use through additional funding, resources, and access to additional clinical samples."
Iceni's vision is for a sugar-based, lateral flow assay for SARS-CoV-2 that patients can take at home. Yet, its efforts are backdropped by a flurry of activity by some of the industry's largest players — such as Roche, Abbott, Thermo Fisher Scientific, Hologic, DiaSorin, Quidel, and BioMérieux to name several —to bring new real-time PCR tests to market. RT-PCR remains the main technology used to diagnose the virus.
At-home tests are also being developed. This week, Scanwell Health said it secured exclusive rights to license and distribute a SARS-CoV-2 antibody-based serology at-home test from Chinese biotechnology firm Innovita.
Clarke, though, was skeptical about the viability of molecular tests in the long run.
"Bacteria and viruses mutate rapidly, driving the need for new diagnostics and vaccines," Clarke said. Viruses, he noted, use glycans when they infect individuals. By the same principle, one can determine the virus by the chain of glycans it uses when it infects them. This chain of sugars does not vary, even though the genetic sequence of the virus might change.
"Recognition of the host by its sugar code is essential for pathogens and this does not change year-on-year," he said.
Iceni's current prototype is being developed to detect a single virus. However, the firm is planning a next-generation test to discriminate among a number of pathogens that cause similar symptoms. This should allow users to distinguish between flu and SARS-CoV-2 in a single sample.
Should Iceni see uptake of its approach, Clarke said the firm has the supply chain in place to meet market needs. "Production of all reagents will be undertaken in-house but assembly of final [lateral flow assay] devices will be via established manufacturers under appropriate regulatory protocols," said Clarke. He also said the firm is currently engaged in discussions with potential global manufacturers and distribution partners to make and sell the test worldwide.
While Clarke believes that glycation patterns might hold the key to at-home testing for SARS-CoV-2, others think that molecular tests, including those that rely on antibodies, can also deliver up information that sugar codes cannot.
Paul Davis, CSO at Mologic, a UK-based developer of lateral flow assays and diagnostics, acknowledged that glycation patterns are a "neglected area of biorecognition," and said such tests have "great potential in diagnostics."
Still, there could be an advantage in using an antibody-based test to discriminate between a pathogenic mutant and a non-pathogenic mutant, he said. "What if SARS-CoV-1 has the same glycan fingerprint as SARS-CoV-2?" asked Davis. "We know that there are big differences in protein structure as detected by antibodies, and I can see why that could be useful," he said. "If, during the current pandemic there's a mutation to SARS-CoV-3 that affects the virulence one way or the other, we would want know which mutant was present in a patient."
Mologic is also developing a test for SARS-CoV-2. Earlier this month, the company received a £1 million ($1.3 million) grant from the Wellcome Trust and the UK Department for International Development to develop a point-of-need test for the virus, as well as to initiate research for vaccine candidates.
Joe Fitchett, medical director at Mologic, earlier this month described the assay as an integrated antigen-antibody test that relies on both saliva and whole blood drawn by finger prick. Mologic has developed multiple assays for infectious disease based on lateral flow technology.