Dry eye, Feature, Report, Therapies

New approaches targeting dry eye subtypes

In Part 1 of Insight’s dry eye series, Dr Laura Downie explains how an explosion in global investment in dry eye research and development is paving the way for a range of new therapies, particularly those more specifically aimed at dry eye subtypes.

It’s well documented that the basis of any effective dry eye management plan involves the crucial task of determining the disease subtype. Evaporative or aqueous-deficient? While it’s a simple concept for most eyecare professionals to grasp, accurate and timely diagnosis and subtyping remains a major clinical challenge that’s yet to be overcome.

Associate Professor Laura Downie, research leader of Downie Laboratory – an anterior eye, clinical trials and research translation unit within the University of Melbourne – has made it her mission to fill this gap in clinical knowledge.

She has led efforts to develop ADMiER, a point-of-care test for rapid and accurate dry eye diagnosis and subtyping that she hopes to bring to market by 2025.

In simple terms, the device has been designed to analyse the stretching properties of a small tear droplet, to objectively diagnose and subtype dry eye. As the first application of microfluidic extensional rheometry for ophthalmic diagnostics, it is said to be a transformative advance over current clinical tests.

With dry eye disease affecting approximately one in five adults, Downie says clinicians can now access a range of therapies to treat this chronic condition, but it’s important to know which to use at the appropriate time.

“Accurate and early diagnosis of dry eye disease is currently a major clinical challenge, as many of the current tests are invasive, time-consuming and inaccurate,” she says.

“It is of critical importance to determine the predominant subtype, evaporative or aqueous-deficient dry eye, as this informs treatment decisions. However, currently there is no single, objective method to both diagnose and subtype dry eye disease.”

Downie is leading the novel ADMiER project in collaboration with Professor Leslie Yeo and Dr Amarin McDonnell from RMIT University.

To date, they have built a research-grade prototype and secured a strong intellectual property (patent) portfolio. An initial clinical dataset has been published that demonstrates proof-of-concept for ADMiER’s diagnostic utility.

These data were published in leading journal Ophthalmology. Downie has also presented on ADMiER’s technology at several scientific meetings, including the Association for Research in Vision and Ophthalmology (ARVO), International Ocular Surface Society meeting, Accelerating Australia Life Sciences Innovation Showcase (Sydney) and the World Congress of Inflammation (Sydney).

In 2019, the team was awarded a National Health and Medical Research Council (NHMRC) grant to support further development and commercialisation of the technology.

“This next stage of development focuses on undertaking a body of research relating to clinical validation of the device and developing and optimising a next-generation prototype,” Downie explained.

Downie and her team hope to bring the device to market within the next five years.

Looking at the broader issue of dry eye, she believes it is critically important that there continues to be innovation in the field, to improve the capacity to identify and treat the condition, and thereby ensure the best outcomes for dry eye patients.

According to Downie, during the past two years there has been a 400% increase in the development pipeline for dry eye therapeutics.

She speculates that with this increase in global investment, a range of new dry eye therapies is expected to become available, particularly those more specifically targeted at subtypes.

“There has been increased global awareness about the importance of diagnosing and managing dry eye disease, particularly through the work of the Tear Film and Ocular surface Society (TFOS), and the publication of the International Dry Eye WorkShop II (DEWS II) reports in 2017,” she says.

“We are seeing increased engagement amongst Australian eyecare clinicians in the area of dry eye disease; this is evidenced by eyecare professionals’ attendance at continuing education events, and the dry eye-focused content of many recent professional development programs.”

As in other fields of ophthalmology, Downie is seeing an increased emphasis on the use of advanced imaging technologies to provide insight into the pathophysiology of dry eye disease.

Dr Laura Downie is an associate professor and a Dame Kate Campbell Fellow in the Department of Optometry and Vision Sciences at the University of Melbourne.

“For example, in vivo confocal microscopy of the cornea enables high-resolution imaging of dendritic cells (innate immune cells) in the living cornea, which can be used to gain insight into anterior eye inflammatory responses,” Downie notes.

“Other technologies, such as infra-red meibography, interferometry, and high-resolution anterior segment optical coherence tomography are also being employed, in clinical and/or research settings, to characterise the structural and functional sequelae of the condition.”

NEXT: Dry Eye Directory grabs global attention