A Colorado Springs company is in search of the “holy grail” of treatment for blocked peripheral arteries, but some medical experts question whether its clinical trials are long enough to prove the efficacy of the new device.
Spectranetics launched the trial of its turbo booster laser catheter — designed to vaporize tissue build-up around stents — in Germany this week. The 100-patient study will last a year, said CEO John Schulte.
Many products have tried to reduce the number of repeat surgeries needed to treat blocked arteries in the legs — and just as many have failed, said Paul Connaughton, interventional radiologist at Memorial Health System.
“It’s the holy grail of the field,” he said. “There are so many products that try to stop repeated treatment at the outset, but none of them have been very good.”
The standard treatment for peripheral pain caused by blockages that restrict blood flow in the legs is to insert a stent — a procedure that works very well for restrictions of blood flow in heart vessels.
But in the legs, the blockages are more severe and longer, sometimes as much as 100 times longer. And in the legs, the stent can fracture, or the body can respond negatively, creating tissue build-up in the area of the stent — necessitating repeat surgeries to deal with the build-up.
“It happens quite a lot,” Connaughton said. “Probably up to 40 to 50 percent have to have repeat treatments within three years. You have to go back and use the balloon again, or put a stent inside the stent. If it’s severe enough, we have to do a bypass.”
The turbo booster is intended to reduce the need for repeated treatments by “vaporizing” the tissue, Schulte said. And, he said he believes a single year of trials will be enough because most patients have to have a follow-up procedure performed within 10 months.
But Connaughton said doctors need much longer studies — at least three to five years.
“So may things have been tried, that we need a good, long time to see if the effects are better than anything else out there,” he said. “If we can prevent re-treatments in the first place, that’ll be great. But we need long-term studies, not just a single year.”
Data from the trial also should be compared with traditional surgical methods, Connaughton said. Memorial treats about 200 patients a year with either vascular or radiological intervention. Many more patients are prescribed medicine or exercise to treat the problem.
“The idea now is not to do big surgical procedures,” he said. “We want to use the minimally invasive techniques, so finding something that works — like this laser treatment — would be great, better than the traditional methods.”
Schulte said he believes the turbo booster will be better than traditional — or even some of the newer — procedures.
“Our hope is that we’ll be so successful that the turbo booster will have a 60 or 70 percent efficiency rate — patients that don’t need a second procedure,” he said.
More than 100,000 patients receive treatment for instent restenosis each year, so if the laser is proven to be effective it also could be very profitable. Schulte said that approval by the Food and Drug Administration could mean up to $200 million for the company’s bottom line.
But there are competing technologies, created by pharmaceutical giants.
Boston Scientific Corp. has a “cutting balloon” that performs an angioplasty in the vein and cuts out built-up tissue. Other competition includes the sculpting balloon and the cryoplasty balloon, which freezes tissue in order to keep it from building up around the stent.
“But none of the treatments now are effective all the time,” Connaughton said. “The devices just don’t work. The body is responding to the stent by building tissue around it, so the problem is halting that build-up.”
The Spectranetics trial is based in Germany because the company’s technology doesn’t have an indication from the FDA for treatment of instent restenosis.
“This lets us have the freedom without the FDA’s involvement at this point,” Schulte said. “We can get the data early; get it more quickly before we go to the FDA.”
But there’s no escaping the FDA, said Regis University professor Mike Fisher, who owned a medical device company for 20 years.
“You can’t escape the tentacles of the FDA,” he said. “There’s the same level of rigor and paperwork no matter where the trials take place. It might be less expensive to do it in Germany, but having the trials there won’t allow them to escape the FDA. And the process is much more imposing that it used to be. The silicon breast implants debacle and some other things really tightened up the procedure.”
With a Class III device like the laser — the most invasive kind — the process can take years and cost hundreds of thousands of dollars, he said.
Spectranetics is conducting a similar study in the United States using the turbo booster without the additional angioplasty treatment — replacing the stent with a Gore-Tex covering.
But the Gore-Tex covering will add another layer of scrutiny from the FDA, Fisher said, because the company will be required to test the bio-compatibility of the coating.
Spectranetics also is conducting studies to show the ultraviolet light from the laser doesn’t harm the artery itself, a safety test required by the FDA.
While initial approval from the FDA could take years, Spectranetics isn’t waiting to get the word to doctors. The company plans to update cardiologists and radiologists within 30 days from the start of the trial.