UCLA researchers seek patients with coronary artery disease who are scheduled to undergo interventional coronary artery procedures to compare the safety and effectiveness of Absorb, a naturally dissolving stent that is an investigational device in the U.S., with XIENCE, an already-approved commercially available metallic stent.
The study will enroll approximately 3,000 subjects at 140 sites in the U.S. and will follow patients for five to seven years.
Coronary arteries, the main blood vessels that supply oxygen and nutrients to the heart, sometimes narrow, which restricts blood flow to the heart and can cause chest pain and other symptoms. The narrowed areas of the heart artery are called lesions.
To increase the blood flow through the narrowed heart artery, doctors can perform a procedure called an angioplasty, in which a balloon is inserted and temporarily inflated where the artery is narrowed or blocked. The balloon pushes the blockage against the artery wall and opens up the heart artery to improve blood flow to the heart.
The procedure is often followed by the placement of a drug-eluting stent, a small metal mesh tube coated with medication, in the narrowed area of the artery to help keep the artery open and decrease the chance of the artery narrowing again. The stent stays in the heart artery wall permanently. In this study, XIENCE, an FDA-approved drug-eluting stent will be used.
That device will be compared with the Absorb Bioresorbable Vascular Scaffold system, or Absorb BVS, a temporary device that functions like a drug-eluting stent but is not made out of metal.
“Absorb is made of polylactide, a naturally dissolvable material that is commonly used in medical implants, such as dissolving sutures, and completely dissolve over time,” said Dr. Jonathan Tobis, the study’s principal investigator and a clinical professor of cardiology at the David Geffen School of Medicine at UCLA. “After two years, the artery heals and expands with each heartbeat, unlike after a metal stent is placed where the stented artery remains rigid.”
“Over time, the BVS material will gradually break down and be resorbed into the artery wall, leaving behind no permanent implant. The absorbable stent is a combination of a scaffold that helps to keep the artery open and the drug everolimus mixed with a bioresorbable polymer that helps prevent re-narrowing of the heart arteries.” Dr. William Suh, assistant clinical professor of medicine in the division of cardiology at the Geffen School of Medicine, said, “This may help determine whether there is benefit from the absorbable stent in decreasing the rate of the re-narrowing as well.”
Participation in the study will last five to seven years, include a total of up to 10 visits after the study procedure including a telephone call or office visit after one, three, six and nine months, and at the end of each year. Study volunteers will be randomly assigned to treatment. They will find out which device they have received only at the end of the study.
Prior to the procedure, participants will complete an interview, blood tests, an electrocardiogram and a health assessment questionnaire. Women of childbearing potential will also undergo a pregnancy test. During the procedure, all study subjects will receive a coronary angiogram to look at the narrowed heart arteries and determine whether the volunteer can be registered in the study. Volunteers will meet with a registered dietician who will provide instruction in following an American Heart Association low-fat diet during the study.
The clinical trial is funded by the vascular business of Abbott, the maker of both devices.
For more information and to discuss potential risks and benefits, please call the UCLA division of cardiology at 310-794-4797.
Roxanne Moster (310) 794-0777