Why?
Cardiovascular disease, including heart disease and stroke, kills about 80,000 Canadians each year. Coronary artery disease (CAD) is a leading cause of cardiovascular disease.

Most cases of CAD are due to atherosclerosis, the build-up of plaque in the blood vessels. When the arteries that supply oxygen-rich blood to the heart become blocked, heart attack and other complications may result.

Decades ago, surgeons would perform open-heart surgery to create a bypass around a blocked portion of artery. The procedure was invasive, however, and recovery time was lengthy.

Balloon angioplasty to dilate blocked arteries was the first improvement over bypass surgery. Then, about 15 years ago, surgeons started using metal scaffolds, or stents, to keep arteries propped open following angioplasty.

"The problem was...the body knew a piece of stainless steel shouldn't be sitting in a valuable piece of anatomy," says William Hunter, co-inventor of the TAXUS™ drug-eluting stent. In approximately 20 to 25 percent of patients, scar tissue would grow through the scaffold and re-block the artery, a process called restenosis.

"It was time for innovation," says Lindsay Machan, a physician, UBC professor, and Hunter's co-inventor and business partner.

The TAXUS™ stent elutes the drug, paclitaxel, which prevents scar tissue from growing into the stent and re-clogging the artery. Patients with the drug-eluting stent avoid the trauma of repeat surgeries. The drug-eluting stent is even effective in diabetics, who have an especially high risk of restenosis.

By improving CAD patients' quality of life, the TAXUS™ drug-eluting stent is also saving health care dollars.

More Canadians die of cardiovascular disease than any other disease. Cardiovascular disease also costs the Canadian economy $18 billion a year.

How?
TAXUS™ stent co-inventors William Hunter and Lindsay Machan first hit on their idea for a drug-delivery device while Hunter was a third year medical student at the University of British Columbia.

In the early '90s, as part of his vascular rounds, Hunter was giving a talk on "a piece of esoteric science." Afterwards, Machan—reportedly the only member of the audience to stay awake—approached Hunter about putting their ideas together.

A drug-eluting stent would solve a longstanding medical problem—restenosis, the overgrowth of scar tissue into the very device meant to keep the artery unblocked.

"It was a simple concept," says Hunter, "but the execution of it was a fair bit more complicated."

The two researchers worked with Hunter's then-graduate supervisor, Larry Arsenault, at the University of British Columbia to develop the first incarnation of the TAXUS™ stent. In 1992 the three men founded the company that would become Angiotech Pharmaceuticals, Inc.

The three researchers then tested various drugs to find one that would inhibit restenosis. The most effective drug turned out to be paclitaxel (also known as Taxol®), an anti-cancer drug derived from the Pacific yew tree.

The next step was to devise a method to use the stent, itself, as a platform to deliver paclitaxel right to the blood vessel walls.

The idea of putting a drug and device together was very new, explains Machan. At the time, the U.S. Federal Drug Administration didn't even have an office to deal with the technology.

Eventually, however, Hunter and Machan were able to get the device companies' attention. Commercial development by Boston Scientific Inc. and Cook Inc. followed in 1997, and clinical trials began in 2000.

Human trials proved the system's efficacy, and as of November 2005, over 1.8 million TAXUS™ stents had been implanted in patients around the world.

"It's really amazing to me to see that in the last ten years, we've gone from being a couple of scientists doing some experiments to a company that people rely on as their place of employment..." says Machan, adding that "physicians around the world are using our product."

This year, the Ernest C. Manning Awards Foundation will award a total of $165,000 in prize money. Four awards, totaling $145,000, will go to leading Canadian innovators. Another $20,000 will go to Young Innovators with winning projects at the 2006 Canada-Wide Science Fair.

The Foundation was established in 1980 in the name of prominent Alberta statesman, Ernest C. Manning, to promote and support Canadian innovators. Since 1982, the Foundation has presented over $3.6 million in prize money through its annual awards program (www.manningawards.ca).