New techniques to treat emphysema show promise

Temple's Gerard J. Criner sees patients picking a treatment.
Temple's Gerard J. Criner sees patients picking a treatment.
Posted: April 14, 2013

In advanced emphysema, the lungs become progressively enlarged and overinflated. Sufferers are literally stuck holding more and more of their breath.

Researchers have long tried to find ways to reduce lung volume and improve airflow without resorting to risky surgery.

Now, three promising lung-shrinking techniques - coils, one-way valves, and an injectable sealant - are in or near clinical testing at Temple University and other U.S. medical centers. All three methods are already approved in Europe.

"They all have pluses and minuses," said Temple University pulmonologist Gerard J. Criner, a leading emphysema researcher. "I foresee a day where a patient would have several of these techniques, based on their anatomy."

Criner estimated that day is still about five years away in the United States, and there are no guarantees. Two years ago, for example, the commercial development of airway stents - tubular supports that opened new lung passages to release trapped air - was abandoned after researchers, including Penn lung-transplant pioneer Joel Cooper, reported disappointing results from a major study. The main problem was that airway stents became blocked, much like stents designed to keep heart vessels open.

Still, biotech companies are doggedly pursuing new technology, recognizing the vast need. Emphysema, which is usually caused by smoking, afflicts about 60 million people worldwide, including four million Americans.

"It is a difficult disease," said pulmonologist Frank Sciurba, director of emphysema research at the University of Pittsburgh. "We've used drugs for symptom relief. Now, we're trying to do things that structurally improve the mechanics" of the diseased lungs.

A decade ago, researchers thought they had a breakthrough with "lung volume reduction surgery." A federally funded study showed that cutting out diseased tissue improved patients' exercise capacity and quality of life - the only treatment short of a lung transplant to do so. Surgery even improved survival for a subgroup of patients.

Nonetheless, the surgery is rarely performed anymore, mostly because it is perceived - unfairly, proponents say - as too risky. (After two years, a quarter of patients had died, whether they had surgery or medical therapy.)

"The surgery is almost nonexistent, even though we proved it works," Sciurba said.

Since then, the goal has been to find simpler, safer, minimally invasive ways to reduce lung volume.

All three approaches now being tested are deployed through a bronchoscope - a long, flexible tube that is threaded through the nose or mouth to airways in the lungs.

The lung coils, developed by PneumRx of Mountain View, Calif., are the newest innovation. The four-inch-long device, made of a super-elastic alloy, is straight when released into the airway, then recoils into a double loop that catches and compresses diseased tissue - sort of like gathering a curtain on a rod - making it far easier to breathe. Each lung gets 10 coils.

Linda Sachs, 65, of Hampton Township, near Pittsburgh, two months ago became the second American to get the coils during a one-hour procedure at the University of Pittsburgh Medical Center.

"After the anesthesia wore off, I told Dr. Sciurba I noticed a difference immediately," she said.

Now, for the first time in years, she can carry a load of laundry up stairs - one of many minor tasks that had become a herculean feat due to her emphysema.

She will have to undergo rigorous evaluation to separate any placebo effects from real ones. And the history of lung-shrinking technology suggests that breathing improvements tend to be modest.

In late 2008, for example, the U.S. Food and Drug Administration refused to approve one-way valves designed to reduce the volume of diseased lung tissue, thus improving the function of healthier parts of the lungs.

"It worked in some patients, but overall, it was not a dramatic effect," said Sciurba, one of the study's leaders.

But the valve technology was acquired by a new company, Switzerland-based Pulmonx, which has developed a pulmonary assessment system to identify the most suitable patients and the best placement of valves. Last year, it announced plans for a new U.S. trial, co-led by Temple's Criner, to begin this year.

Temple is also a test site for the latest version of a sealant, made by Aeris Therapeutics, that permanently collapses and seals selected areas of the lung.

Criner is not concerned that smoking-related emphysema is preventable. "We're all human beings," he said. "A lot of things we do when we're younger aren't very smart."

What matters, he said, is that science is finally making progress in understanding the biology, mechanics, and genetics of a common, suffocating illness.

"It's a pretty exciting time to be working on a disease that is third leading cause of death in the world," he said.


Contact Marie McCullough at 215-854-2720 or mmccullough@phillynews.com.

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