Optical Solutions

‘Stick a needle in your eye’ – the age-old, cringe worthy turn of phrase that immediately conjures up pain and discomfort might well become obsolete, thanks to leading edge technologies and therapies Heather Sheardown and her research team are developing in her lab.

Sheardown, a professor of chemical engineering at McMaster University in Hamilton, ON, was recently appointed Canada Research Chair in Ophthalmic Biomaterials and Drug Delivery Systems. Her research has established the University as a globally recognized centre for research into the development of new drug delivery systems and new biomaterials for treating ocular conditions.

Whether it’s developing better biomaterials for contact or intraocular (implanted in the eye) lenses, or determining the best method to deliver therapeutic drugs to the back of the eyes of patients suffering from diabetic retinopathy or macular degeneration, Sheardown has been at the forefront of the research that could be translated into novel treatments for a host of ophthalmic diseases.

“Finding new ways to deliver drugs to the eye, particularly the back of the eye, is the greatest single challenge in ophthalmology,” says Sheardown. “People suffering from macular degeneration, glaucoma and other conditions need us to find ways to deliver precise amounts of drugs targeted to the desired tissue and we’re well on our way to doing just that.”

Diseases of the eye are a significant burden to society, says Sheardown, citing estimates of almost one million Canadians who are visually impaired with more than three million suffering from diseases such macular degeneration and glaucoma- numbers that are expected to double over the next 25 years, according to Sheardown. “The incidence will only rise as our society ages,” she says, noting that women are more vulnerable as estrogen levels trigger many of these diseases.

Much of Sheardown’s work is carried out at the McMaster Biointerfaces Institute –the first institute of its kind in Canada, and among the first in the world to use high-throughput synthesis and screening technologies coupled with advanced surface characterization methods to provide a new understanding of the nature of the biological and material interface. She’s using the institute’s high-tech capabilities to experiment with materials designed to improve eye health, and she’s making incredible progress.

It’s there that she and her team are looking at remedies for infectious diseases in the eye and the most effective and least invasive delivery of antibiotics in the eye. McMaster is internationally known for its infectious disease research.

In terms of infectious diseases, the eye is incredibly susceptible considering it’s a relatively immune-privileged organ. A common complication of monthly injections is endophthalmitis – an infection inside the eyeball or the globe, near the back of the eye. It is among the most serious complications and can lead to blindness or even total loss of the eye.

“Endophthalmitis is very difficult to treat because the eye is a closed globe,” she explains. “It can be caused by trauma (monthly injections) or in cataract surgery, for example, when the lens is removed and a new lens put in, there’s a risk of secondary infection.”

To combat these ‘difficult-to-treat’ infections, Sheardown is developing biomaterials to specifically target the infection either as a single antibiotic injection or to deliver it across the ocular tissue – as opposed to putting it into the eye. Similarly, she’s looking to improve antibiotic delivery for front of the eye infections, like those in the cornea, which can require drops every 15 minutes.

“Understanding the infection – whether it’s bacterial, fungal or viral – is critical to determining the best course of antibiotics,” she says, adding that having access to the Biointerfaces Institute’s diagnostics work is the ‘perfect marriage’ of disciplines.

Developing the technology is one thing, commercializing is yet another, but Sheardown is well on her way there.

Sheardown’s team developed a treatment for dry eye diseases. While these diseases are considered merely ‘inconvenient,’ millions are afflicted with little treatment choice on the market. Her treatment is based on this being an inflammatory disease and she’s looking at the cause of that inflammation.

“It’s a mucoadhesive system which sticks to the cornea – a polymer that’s in the eye naturally so it sticks and stops that inflammation from occurring,” she explains.

And even better, Sheardown’s optimistic it could be on drug store shelves in the very near future. “It’s a material, not a drug, so the regulatory hurdles are very small.”