News:Biolimus Eluting Stents Shown to be as Safe and Effective as Sirolimus Eluting Stents in Everyday Clinical Practice: Results from the LEADERS Trial

September 1, 2008 by Scott P. Williams [mailto:swilliams@perfuse.org]

The LEADERS Trial enrolled 1,707 patients with coronary artery disease (defined as stable angina, silent ischemia, and acute coronary syndrome) and at least one lesion of equal to or greater than 50%. Patients were randomized in an assessor-blind manner to either biolimus eluting stent (n=857, with 1257 lesions treated) or sirolimus eluting stent (n=850, with 1215 lesions treated). Patients in each arm of the study were then randomized in a 1:3 manner to 9 month clinical and angiographic follow up or clinical follow up alone, respectively. The LEADERS Trial allowed off-label use of the stents to better reflect their use in everyday clinical practice. Procedural and patient characteristics were similar in both arms of the study. Recruitment occurred at 10 clinical sites spread throughout Europe.

The trial’s primary clinical endpoint was defined as the occurrence of cardiac death, myocardial infarction, or clinically-indicated target vessel revascularization at 9 months. The study set the non-inferiority margin at 4% with a one sided α equal to 0.05. The assumed event rate at 9 months was 8% for both the biolimus and sirolimus arms of the study. 9.2% of patients treated with the biolimus stent sustained this outcome, compared to 10.5% of patients treated with the sirolimus stent (p for non-inferiority = 0.003, upper limit 95%, CI 1.1%).

Similarly, treatment with the biolimus stent resulted in a lower occurrence of clinically-indicated target vessel revascularization, which was a secondary efficacy endpoint (4.4% in the biolimus arm vs. 5.5% in the sirolimus arm; RR=0.79, 95% CI 0.52-1.22).

The principal angiographic endpoint was defined as in-stent percent diameter stenosis at 9 months. The biolimus stent had a mean of 20.9% stenosis(+/- 17.5%), while the sirolimus stent had a mean of 23.3% stenosis (+/- 19.6%) (p value for superiority= 0.26).

The rate of definite stent thrombosis was similar for the biolimus (1.9%) and sirolimus (2.0%) stents (RR=0.93, 95% CI 0.47-1.85). The LEADERS Trial researchers plan to further investigate the long term risk of stent thrombosis for biodregadable polymer stents.

Dr. Windecker stated in a press release that “the results from LEADERS are significant, as they demonstrate for the first time that a drug-eluting stent with a biodegradable polymer is just as safe and effective as a conventional drug-eluting stent with a durable polymer, under conditions which resemble those of routine clinical practice.”

The LEADERS Trial was funded by Biosensors Europe S.A., Switzerland.

Reviewed by C. Michael Gibson, M.S., M.D.