Powering Through Clogged Arteries

FoxHollow's SilverHawk is a promising alternative to stents and bypass surgery

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Surgeon Thomas R. Bernik is midway through an operation in April to unblock a plaque-clogged artery in a patient's leg. A specialist in such procedures at St. Vincent's Hospital in New York, Bernik eschews balloon angioplasty and the use of stents in favor of a novel, catheter-based procedure developed by startup FoxHollow Technologies Inc. (FOXH ) of Redwood City, Calif.

After administering local anesthesia to patient Ronnie Cutler, Bernik inserts a catheter into the artery of one leg and passes it up and over the abdomen, into the artery of the leg with the lesion. "A year ago she was open," says Bernik, pointing to an X-ray image. "Now she is blocked."

While bypass surgery routes around lesions, and stents and angioplasty compress the plaque, FoxHollow's device, called the SilverHawk, is like a Roto-Rooter. Once the catheter is in position above Cutler's knee, Bernik switches on the spinning blade inside the plastic tube. He pushes the device through the lesion, rotating it to chop through the plaque and remove it. An X-ray now shows blood flowing through the artery. Before the operation, severe leg pain kept Cutler from walking more than two blocks. A month later, she reports that all systems are normal again. "I got my life back," she says. "I can walk."

FoxHollow's SilverHawk is quickly emerging as one of the most promising new treatments for diseased arteries. The company was founded in 1996 to commercialize the SilverHawk, but it didn't take off until June, 2003, when the U.S. Food & Drug Administration approved the device to treat atherosclerosis in the peripheral arteries. FoxHollow eventually aims to seek FDA approval for cardiac uses, but for now, the leg business is booming. The company expects $105 million in sales this year. And while it will probably post a $15 million loss, analysts who follow the company say it could earn $7 million on $150 million in sales next year. "They have a first-mover advantage in developing this market," says Michael Weinstein, an analyst with JPMorgan Securities Inc.

In a fast food nation, peripheral artery disease (PAD) is prevalent yet underdiagnosed, affecting as many as 12 million U.S. adults. Symptoms may begin with numbness in the leg but can proceed to excruciating pain. Left untreated, PAD can increase the risk of heart attacks and stroke. Patients are told to change their diets, quit smoking, and take other steps. But for several hundred thousand people a year, the ailment leads to bypass surgery, stents, angioplasties, and, in the worst cases, amputations.

The SilverHawk is the brainchild of Dr. John B. Simpson, a noted physician and entrepreneur who has founded several other medical-device startups that were all acquired by leading health-care companies. Now FoxHollow's chairman, Simpson says he was motivated by the devastating consequences of PAD. "My dream is to stamp out amputation in this country," says Simpson, who works in private practice and is a professor of clinical medicine at Stanford University.

While stents and bypass surgery have worked well in the heart, these procedures are less effective in the peripheral arteries, many doctors say. "Stenting works great initially, but the metal cracks," says Dr. David Cohen, a cardiologist at St. Joseph's Regional Medical Center in Paterson, N.J., who moved away from using stents and angioplasty balloons 18 months ago to focus on the SilverHawk. Stents fracture in up to half of all patients, says Cohen, mainly because of pressure from standing and walking. And balloon angioplasties result in "restenosis," or renarrowing of the artery, in 33% of patients. By comparison, early case studies of the SilverHawk show restenosis rates of 12% after six months. On June 16, FoxHollow will release 12-month trial data at Society for Vascular Surgery's annual meeting in Chicago.

Ray Kite, who had repeated angioplasty on his legs, attests to the difference. The 64-year-old resident of Salado, Tex., would feel good for several months after the procedure, but then the intense pain would return, he says: "It's like lightning strikes inside you." Kite also balked at leg bypass surgery after he came down with a staph infection following a heart bypass. Facing a possible amputation, he opted for the SilverHawk last October. The pain left his leg and hasn't returned. "I walk all over my ranch," he says.

Some medical experts say it is too early to gauge safety and efficacy for such a new device. Dr. Jeffrey A. Brinker, a professor of medicine at John's Hopkins University School of Medicine who has served on the FDA's cardiovascular device panel, says he has seen a long line of ballyhooed devices like the SilverHawk that have not lived up to their potential. While he thinks there may be a niche for the SilverHawk, he would like to see controlled, peer-reviewed clinical studies that track patients' progress for several years. "The initial results don't necessarily predict later outcomes," says Brinker.

Chief Executive Robert W. Thomas says FoxHollow won't conduct such trials. It's too hard to find patients who have tried multiple approaches, and unfair to ask participants in a double-blind trial to accept what Thomas deems an inferior treatment. "It's not a good choice for the patient," he says.


Thomas believes the rapid adoption of the product speaks for itself. In the quarter ended Mar. 31 of this year, 775 hospitals had used the SilverHawk, up from 576 the previous quarter. JPMorgan's Weinstein estimates that SilverHawk will be used in 47,000 procedures this year, or about 10% of the total market. "We're getting to be mainstream," says Thomas.

Some experts believe FoxHollow will be able to apply the technology in new areas. Having received FDA approval for peripheral arteries, it's "highly likely that they will be able to demonstrate safety and effectiveness for the coronary arteries," says Dr. Stuart Portnoy. The senior director of medical-device consulting for Pharmanet Inc., a pharmaceutical consulting group, Portnoy worked at the FDA for eight years as a clinical reviewer for cardiovascular devices.

FoxHollow is now waiting for the FDA to approve a trial for bifurcation lesions in the heart and hopes to start the tests later this year. Such lesions, which occur in about 20% of patients with coronary artery problems, block the vessels of a main artery and its side branch. FoxHollow halted an earlier trial for coronary arteries after 28 out of 172 patients suffered adverse events, including 14 cases of heart attack and 8 patient deaths, according to financial filings. The company said the problems "resulted from a number of factors, including the patients' overall poor health."

The bifurcation trial's principal investigator, Dr. Jeffrey W. Chambers, a cardiologist at Mercy Hospital in Coon Rapids, Minn., says the company has designed a new device for the trial that is more precise. Chambers and other doctors say the SilverHawk could prove more effective in treating bifurcation lesions than other therapies, such as stents. "I think the chances of it being useful are high for this application," says Chambers.

FoxHollow has plenty of other challenges in the meantime. The company already offers five versions of the device and is busy developing machines that are smaller and able to cut calcified plaque. For Simpson and FoxHollow, the key to success is continual innovation.

By Spencer E. Ante in New York

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