Some time towards the middle of 2015 we embarked on a project that would result in the world’s first over-the-counter, fully at-home COVID-19 diagnostic test. We just didn’t know it yet. Fast forward a few years, and the Cambridge Consultants team was elated to hear the news that the product in question has now been granted FDA Emergency Use Authorisation for non-prescription home use by adults and children aged two years and above, with or without symptoms.

It’s a well-worn phrase, I know, but this truly is a gamechanger. The rapid, at-home COVID-19 antigen test from digital diagnostics company Ellume is going live at a critical point in the global pandemic. It is set to reduce the spread of the virus in the United States and help facilitate a safe return to work, education and travel. But none of it would have been possible without the core sensing technology developed here at CC. Let me explain.

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As a senior consultant specialising in system design, optical physics and optical engineering, I was part of a great team of colleagues that took those early meetings with Ellume Founder and Managing Director Dr Sean Parsons. As an experienced Emergency and Intensive Care physician, he’d founded the Australian start-up with a mission to discover faster, simpler and more accurate ways to diagnose influenza and other infectious diseases.

We assembled a global, multidisciplinary project team to take up the challenge from Ellume. The primary ambition then was to develop an over-the-counter (OTC) rapid flu test (RFT). But there was also a desire to facilitate direct access to anti-viral drugs based on a positive result, and to provide surveillance data on the course of a pandemic. Sean’s concerns about the threat of a pandemic and the need for OTC diagnostics were certainly prescient.

Ultra-sensitive optoelectronic detection

It was during this flu-focused project that we developed the hugely significant core sensing breakthrough, which is based on an ultra-sensitive optoelectronic detection system. For the COVID-19 home test, this has been coupled with Ellume’s supercharged fluorescent immunochromatography, using a quantum dot fluorescent particle, which delivers world-leading sensitivity and specificity.

During his hectic round of media interviews as the world reacted to news of the FDA authorisation, Dr Sean Parsons was generous enough to pay tribute to the “geniuses” at Cambridge Consultants for working out the electronic and optical configuration. “Without the brilliance of CC in the early days, we certainly wouldn’t have accomplished what happened just now,” he said.

That’s great for the team to hear obviously – but the feeling is mutual. Sean is a passionate advocate of positive change who came to us with a strong vision. The project was characterised by collaboration from the get-go, and a strong relationship was forged with Sean and Dr Scott Fry, Ellume’s assay lead. In the early days, we drew on our past experience of lateral flow design and swapped ideas with more reliance on shared whiteboard ink than individual PowerPoint presentations.

Ellume had already established the baseline context as lateral flow test, similar to a digital pregnancy test, but with fold-out wings to facilitate nose-blow collection. The key challenges ranged from reader, signal chain, assay (client led), optics, electronics and algorithm through to fluidics. Matters of design, for ease-of-use and high-volume, low-cost manufacture of moulded optics, case and functional parts were also addressed.

High performance at low cost

Groundbreaking developments do not always follow their intended course and Ellume experienced issues with its novel sample capture method which caused a redirection of the original RFT programme. We helped the Ellume team embark on the next stage of the journey, which was to reformat the product as a point-of-care reader and cartridge solution – still with the core reader and assay now proven to offer high performance at low cost. The trajectory of the journey has of course now been altered significantly. But consistent with Sean’s ambition, the core technology represents a versatile platform that can be applied to different applications, including home-testing for COVID-19.

The Ellume COVID-19 Home Test includes a sterile, self-collected mid-turbinate nasal swab and a Bluetooth® connected analyser linked to a smartphone app. In an independent US clinical study, the test demonstrated 96% accuracy compared to an Emergency Use Authorisation molecular test.

It’s good to know that our ultra-sensitive optics, front-end electronics and core measurement software – as well as selecting the system architecture and signal chain analysis from sample in to answer out – has led to a self-test that will provide critical support to the United States as it transitions out of the pandemic. Yet Sean Parsons always had a strong sense that we would benefit from home-use diagnostics in the face of such circumstances. None of us knew how true that would turn out to be.

As for the future, there is no doubt that we will continue to need widespread testing for some time to come. Beyond that, the world will not want to risk a further pandemic without an effective infrastructure to defeat it. This change, at least, will be permanent. Before the emergence of COVID-19, Ellume partnered with QIAGEN N.V. to develop a diagnostic assay for tuberculosis, the leading infectious cause of death in the world, killing more than a million people a year. In my view, the relevance of Ellume’s platform technology goes much further and wider than home tests.

Contact Mike Hazell for more information.

Mike Hazell
Associate Director, Medical Technology Division

Mike is a physicist specialising in the development of high-performance, cost-effective, measurement systems for biochemical assays in the context of diagnostics and life sciences. His experience spans the range from mass-produced, consumer diagnostics through to leading-edge, laboratory platforms.