A new stent, coated with the immunosuppressant and antiproliferative agent everolimus, appears to be safe and effective in preventing restenosis after balloon angioplasty in patients with coronary heart disease, according to an article in the May 4th rapid access issue of Circulation.

The small study of 42 patients compared standard stents with a new stent coated with the drug everolimus in a biodegradable polymer over one year of follow-up. The current study is the first to evaluate everolimus, an agent similar to sirolimus, one of two drugs used for coating stents that was approved in the last year for use in the US. Everolimus had already shown promise at preventing heart and kidney rejection after transplantation.

The two drug-releasing stents approved for clinical use retain their polymer coatings as long as they are in the body. Most of the polymer coating used on the everolimus stents tested in the current study biologically dissolved in a month or so, leaving only the metal stent behind.

“This unique everolimus-coated stent freezes the biological process that leads to the renarrowing of arteries after catheter-based treatments,” said Peter J. Fitzgerald, MD, PhD, senior author. “Not only are the patients free from symptoms, but they have open arteries 12 months after stent implantation.”

The randomized study was conducted at the Heart Center in Siegburg, Germany, by Eberhard Grube, M.D., Shinjo Sonoda, M.D. and colleagues. Average patient age was 64 years. Of the 42 trial participants, 27 received the everolimus-coated stents and 15 received bare-metal stents. Both groups were similar in age, sex, prior heart attacks, smoking, diabetes and hypertension.

The study’s main clinical focus was on major adverse cardiac events (death, bypass surgery, a revascularization procedure on the stent-treated artery, or myocardial infarction). Only two patients in the everolimus group and one in the control group suffered an event during the first six months, and one patient died of chronic obstructive pulmonary disease unrelated to stent treatment. No other major events occurred during the last six months of the study.

Before the study, patients in the coated-stent group had artery narrowing of 64.1 percent. At 6-month follow-up, the narrowing was only 2.6 percent. Among the bare stent group, artery narrowing was 62.1 percent before the study and 27.8 percent at 6-month follow-up. After one year, patients with the everolimus-coated stents had 87 percent less narrowing in the treated portion of their arteries than those who received bare-metal stents.