New drug offers hope against cataracts

A University of Adelaide Chemistry professor is the lead inventor of a world-first drug that is showing great promise in preventing blindness from cataracts.

Professor Andrew Abell in the School of Chemistry and Physics is the co‑founder and chief scientific officer of an Adelaide-based company called Calpain Therapeutics, which is commercially developing the drug.

The drug targets a specific protein - known as calpain - in the eye's tissue. The calpain protein is responsible for the clouding of the lens, forming a cataract.

Severe cataracts are the leading cause of blindness; an estimated 18 million people around the world are blind as a result of this condition.

The calpain protein is activated by various triggers, including those associated with the body's ageing. While most cataracts develop during old age, cataracts can also be caused by diabetes, eye injury, exposure to ultraviolet light from sunlight, long-term use of steroid medication, smoking and heavy drinking.

Currently there are no medications to treat or prevent cataracts and they cannot be reversed; the only option is to have the cloudy lens surgically removed and replaced with a synthetic one.

In 2004 it was estimated that almost 1.5 million Australians aged 55 or over had cataracts. More than 200,000 cataract surgeries are performed in Australia each year.

"Cataract is a major and ever-increasing problem for our ageing population - a quarter of our population aged 80 and over has cataracts," Professor Abell said.

"Unfortunately surgery is the only way to deal with this problem at present, and many people - especially the elderly - don't like having surgery or cannot get it when needed.

"At a social level, this is a huge problem - having cataracts means you can't drive, can't read, you can't get out and about. Quality of life is a big consideration," he said.

A past PhD graduate of the University of Adelaide, Professor Abell began this work with colleagues in New Zealand at the University of Canterbury, Lincoln University and Douglas Pharmaceuticals. He has followed it through to commercial development after joining the University of Adelaide as Professor of Chemistry in 2007.

He said when triggered, the calpain protein becomes over-active and "chops up" the eye's lens, creating the cloudiness. But the drug being developed by Calpain Therapeutics contains molecules that bind to the calpain protein, preventing it from causing further damage.

"Through a routine eye exam, optometrists and ophthalmologists can see the early stages of a cataract forming, likely before the person has any idea they have it," said Calpain Therapeutics founding CEO and Managing Director, Dr Tim Lovell.

"Once the early stages are detected, you could start to use our drug to slow its progress.

"It could be used either as drops or a cream that you put in your eyes each night before you go to sleep. We see it as akin to brushing your teeth each day; you do that to prevent cavities, this would be a drop each day to prevent cataracts.

"And because we know that if you have a cataract in one eye you will most likely get one in the other eye, you could start to apply the drug to both eyes, delaying the onset of a cataract in one while slowing the growth of the cataract that has been diagnosed."

Testing of the drug has shown that it significantly slows cataract progression. "The next stage is to conduct the simplest of human trials," Dr Lovell said.

Calpain Therapeutics is one of four finalists in the prestigious University of Queensland (UQ) Business School's $100,000 Enterprize business plan competition. The winners will be announced on 13 October.