Delivering sight-saving drugs better, for longer

Finding efficient and comfortable methods for the delivery of drugs to the eye remains a significant challenge for vision scientists — and one that University of Waterloo researchers at the Centre for Eye and Vision Research (CEVR) are undertaking in real time.

Under the leadership of Waterloo’s Dr. Lyndon Jones, researchers at Hong Kong’s Centre for Eye and Vision Research are working hard to answer the age-old question: how can we create effective, non-invasive drug solutions for our eyes?

Improving drug delivery to the front of the eye

Because of the tear drainage system, our eyes are naturally adept at removing foreign substances, making eye drops notoriously inefficient, says Dr. Chau-Minh Phan, a lead researcher for CEVR’s drug delivery platform.

“After application, they drain away from the ocular surface quickly. They can overspill. And a large proportion of the drop is absorbed into surrounding blood vessels, steering the medicine away from the front of the eye, where you want it to be most active,” Phan says. Estimates indicate that a person will only absorb about 5 per cent of the medicinal properties from eye drops currently on the market.

From 3D printing to light-activated materials, researchers at CEVR are on the cusp of developing a range of technologies that will enable drug delivery in a time-controlled manner using ocular inserts and contact lenses. Instead of applying multiple drops a day, patients would simply apply an insert at the base of their eye or wear a drug-releasing contact lens for up to a week.

“When your sight is on the line, you want to know you’re getting the best treatment,” Phan says. “The slow-release systems we’re building will increase treatment efficacy while also improving the patient experience."

Replacing eye injections with laser technology

To date, delivering medication to the back of the eye has been the biggest challenge facing ophthalmologists treating eye disease.  

Intravitreal injections — a shot of medicine into the vitreous, a jelly-like fluid at the back of the eye — are currently the gold standard for treating posterior eye disease. Not only does this type of treatment invoke fear in many patients, but Phan says there is also serious risk of infection.

“In most cases, injections need to be repeated frequently — every three months or less for patients with diseases like age-related macular degeneration (AMD). Every time they receive a shot, a patient may experience complications”.

Researchers at CEVR, including Waterloo professor and Nobel Laureate Donna Strickland and professor Melanie Campbell, have zeroed in on an innovative new laser technology that would eliminate the need for AMD patients to receive on-going intravitreal injections.

The leading cause of vision loss in older adults, AMD happens when an abnormal amount of blood vessels grow and leak beneath the retina, causing blurry vision. Using this first-of-its-kind laser technology, practitioners would be able to non-invasively eliminate excess blood vessels to effectively slow the progression of the disease.

Bringing together global talent

Now a year into their work at Waterloo’s hub for global vision research, Dr. Jones says creating the ocular drug delivery research program at CEVR has opened the door to work with incredible talent from all over the world.

“It's been exciting to see the extraordinary pool of talented researchers we’ve been able to assemble at CEVR,” Dr. Jones says.

“With every new collaboration comes new ideas and skills and the opportunity to change the way we’re delivering treatment to millions of patients for the better.”