TCT: No LEADERS emerge in biolimus/sirolimus stent debate
WASHINGTON, D.C.—Biolimus A9-eluting stents showed similar outcomes of major adverse cardiovascular events, MI, death and target vessel revascularization when compared to sirolimus-eluting stents (SES), said Patrick W. Serruys, MD, PhD, of the Erasmus Medical Center in Rotterdam, the Netherlands, when he presented the three-year data of the LEADERS trial said Sept. 23 during the 2010 Transcatheter Cardiovascular Therapeutics (TCT) scientific sessions.

The prospective, randomized, multi-center LEADERS (Limus Eluted from A Durable versus ERodable Stent coating) trial enrolled 1,707 patients and aimed to evaluate the outcomes of a biolimus-eluting stent (BES) stent when compared to the SES-eluting stent. According to Serruys, two-year study data reported MACE rates to be 9.2 percent for BES and 10.5 percent for SES.

The 1,700 patients were randomized to receive either a BES (BioMatrixFlex, Biosensors International) or SES (Cypher Select, Cordis)—857 in the BES arm and 850 in the SES arm. In the BES patient arm, 640 patients received clinical fluoroscopy, while 210 received angio fluoroscopy. These numbers were the same for patients in the SES arm.

Inclusion criteria included patients with coronary artery disease who had at least one lesion with a diameter of 50 percent or greater and researchers recommended duel antiplatelet therapy for 12 months.

Twenty-six percent of patients in the BES arm had diabetes compared to 23 percent of those randomized to the SES arm and 32 percent of patients in the BES arm had previous MI compared with 33 percent of those in the SES arm.

At three years, rates of cardiac death were reported to be 5.2 percent in the SES patient arm and 4.2 percent in the BES arm, what Surreys called “nonsignificant.”

Meanwhile the rates of all overall MI were reported to be 7.2 percent for SES and 7.1 percent for BES, respectively. “Initially there was a higher rate of MI in the BES group, but then we saw a catching effect of the SES, so we really ended up with the same number,” Surreys noted.

Additionally, Surreys said that the rates of combined death and MI diverge and at two years and differed by 8 percent, and 1.9 percent at three years. The current numbers for cardiac death or MI were 11.6 percent (SES) and 9.7 percent (BES), respectively.

At three years, rates of target vessel revascularization (TVR) were 11.1 percent for the SES arm and 9.4 percent for the BES arm, while the overall rates of MACE were reported to be 19 percent (SES) and 15.7 percent (BES).

Surreys noted that the rates of stent thrombosis began to diverge at one year and differences in its rates at three years were 4.7 percent.

Currently, Surreys noted that all patients are still being administered aspirin, while 20 percent continued on clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi-Aventis).

While Surreys said that rates of the three-year safety endpoint of death, cardiac death, MI showed no statistically significant differences, the “rates for the Cypher stent were numerically higher than those for the biolimus A9 stent for cardiac death, similar for MI and numerically higher in the Cypher stent arm when compared to the BioMatrix for the combination for cardiac death and MI.

“In conclusion, the noninferiority of the biolimus versus sirolimus was sustained up to three years and in the overall LEADERS population there were similar outcomes for biolimis and sirolimus stents with respect to MACE, cardiac death, MI and clinically indicated TVR,” concluded Surreys.

“In the central analysis of stent patients, biolimus is favorable if you look at numbers. We can be satisfied by the quality of the three-year follow-up … and I am curious to see what is going to happen at year four and year five.”