Bloomberg News
' disappearing stent, inserted to prop open a clogged artery and absorbed by the body over time, performed about as well as the company's market-leading Xience device in its first scientific trial.
The study showed some early signals of unique benefits and risks from the device, known as Absorb, though patients getting either therapy fared about the same. The findings presented at a conference today in Washington should be reassuring for doctors and patients in Europe, where it has been on the market for the past three years, said investigator Patrick Serruys, head of interventional cardiology at Erasmus University Hospital in the Netherlands.
'At the end of the day, we have shown that in this patient population and in this trial, Absorb is performing as well as Xience, and Xience was very good,' said John Capek, the Abbott Park, Illinois-based company's executive vice president for medical devices. 'Perhaps we are seeing what was reported to be some of the benefits of Absorb, even at one year -- a more patient-friendly implant that has the opportunity to reduce angina.'
Patients treated with Absorb reported less chest pain, a complication that can lead to repeat procedures to clear the arteries, although the finding wasn't definitive, according to the study known as Absorb II. They also were more likely to experience a mild heart attack based on laboratory testing, though the difference may have been the result of chance, researchers found.
Further Testing
Abbott has completed enrollment in another study that is designed to determine if the differences found in the Absorb II are meaningful. Those results should be available in about a year, Capek said in a telephone interview. Abbott is also planning a study looking at chest pain known as angina and cost savings with Absorb, he said.
The study involving 501 people found 4.8 percent of those treated with Absorb suffered a heart attack or needed a repeat procedure in the same artery after one year, compared with 3 percent of those given Xience. A broader measure found deaths, heart attacks and repeat procedures occurred in 7.3 percent of Absorb patients, versus 9.1 percent of Xience patients.
The Xience drug-coated stents $1.6 billion in 2013 sales, Abbott reported.
The findings were presented at the Transcatheter Cardiovascular Therapeutics meeting, an annual event focused on devices inserted via a catheter.
Little Difference
Heart attacks were more common with Absorb, found in 4.5 percent of patients, compared with 1.2 percent of those getting Xience. Repeat procedures were half as likely, at 3.6 percent compared to 7.3 percent. None of the differences were statistically significant from a scientific perspective because the study was so small. The larger trial now under way should clarify the implications of the variations, Capek said.
There is a lot of excitement about dissolving stents, which are designed to reduce the long-term risks tied to the conventional metal devices, said Ajay Kirtane, director of Catheterization Lab Quality at Columbia University Medical Center/New York-Presbyterian Hospital in New York. The Absorb device is thicker than the older models, however, and needs to be carefully studied to make sure it is as safe and effective, he said in a telephone interview.
Earlier data released this summer suggested the thicker struts may lead to more blood clots on the stents, he said. The heart attack risk seen in the current Absorb II must also be closely watched in future studies, he said.
'While the clinical endpoints are very similar between both stents, the finding of a three times higher rate of target vessel heart attack, although of borderline significance, is concerning,' Kirtane said. 'If you look at the overall outcomes, they are great with the stent. But we don't want to be just great, we want to be the best we can possibly be.'
To contact the reporter on this story: Michelle Fay Cortez in Minneapolis at mcortez@bloomberg.net
To contact the editors responsible for this story: Reg Gale at rgale5@bloomberg.net Andrew Pollack, Stephen West
