$4 billion-a-year market for drug-coated stents gets a disappearing act from Abbott

Abbott’s experimental heart stent, a scaffold-like device the size of the spring in a ballpoint pen, was inserted into the first patient in March 2006 and inflated under pressure to prop open the passage, which had been clogged by fatty plaque. Unlike metal stents, Abbott’s is made of polylactic acid and designed to dissolve within two years after implant.

If studies confirm the device helps arteries and disappears without causing clots or other risks linked to metal models, the product may take the lead in the $4 billion-a-year market for drug-coated stents, as it would be safer for patients, said John Capek, Abbott Park, Illinois-based Abbott’s executive vice president of medical devices.

The dissolving stent is designed to confer the benefits of existing devices without leaving behind the “metal spider,” the image that appears during an X-ray of a patient whose coronary arteries are fully stented. Current stents don’t shrink and expand with the artery’s natural movement. The metal devices can trigger deadly clots, and may interfere with future tests and surgeries, Capek said.

There haven’t been any cases of clots in people getting Abbott’s bioresorbable stent, Capek said. Data on 45 patients, who were followed for nine months after treatment, were presented at the Transcatheter Cardiovascular Therapeutics meeting in Washington Sept. 21-25.

Abbott’s approach is part of an evolution, said Patrick Serruys, chief of interventional cardiology at Erasmus Medical Center in Rotterdam, who has been a pioneer of the technology.  Doctors first cleared clogged arteries with a balloon, inflating it inside a blockage to allow blood to flow. The arteries often snapped shut or reclogged, leading researchers to craft metal tubes that were left behind to prop open the vessels.

Abbott’s main competitors in the stent market are in the early stages of evaluating dissolving devices. Most of their work is in places such as the leg where the larger size of an absorbable stent isn’t a problem.

Here’s what BusinessWeek reported on the competition.

Boston Scientific

While Natick, Massachusetts-based Boston Scientific is working on bioresorbable stents for leg and heart arteries, the company’s emphasis in research is something else: metal devices with coatings that dissipate over time, said Keith Dawkins, chief medical officer for the cardiology, rhythm and vascular group.

“There is very little evidence that the long-term presence of a metal scaffold is detrimental,” J&J’s Rogers said. “There are millions and millions of patients with metal scaffolds in their arteries and are doing fine.”

Reva Medical

Founded in 1998, Reva is working on a stent that starts to resorb after 90 days. The company redesigned its prototype after patients who received it in a 2007 study needed repeat treatment. Reva, whose investors have included Boston Scientific and Medtronic, aims to start another trial by next year. Now closely held, the company plans a public sale of securities to be traded in Australia, according to a regulatory filing on Aug. 13.

Biotronik

Biotronik’s bioresorbable drug-coated metal stent, made from magnesium and dubbed Dreams, was implanted in its first patient in August, in Germany, said Sandy Hathaway, a company spokeswoman. Biotronik, founded in 1963 by the developers of a heart pacemaker, is closely held.

Medtronic

"The legs, where the arteries run close to the surface of the skin, present anatomical dynamics that may warrant this kind of biomaterials innovation," says Sean Salmon, general manager of Medtronic's coronary and peripheral division. "The clinical need to reduce pain and amputations remains largely unmet."

Johnson & Johnson

At New Brunswick, New Jersey-based Johnson & Johnson, officials say they aren’t sure how much promise there is in dissolving stents.

“For coronary stents, there is an incredible premium on stent performance,” said Campbell Rogers, chief scientific officer for J&J’s Cordis unit. “You need a Ferrari. The bioresorbable stent is a larger, bulkier stent. The likelihood of it being a significant advance for patients and clinicians in coronary use is not great.”