TCT: Xience performs similarly to Cypher, not more EXCELLENT
WASHINGTON, D.C.--Use of Xience/Promus everolimus-eluting stents (EES) was non-inferior to the CypherSelect sirolimus-eluting stents (SES); however, rates of late lumen loss were higher within the EES arm, perhaps leading to trends in adverse event rates, according to the results of the late-breaking EXCELLENT trial presented at the 22nd annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium.

Because there are no previous data that compare the clinical outcomes of these two drug-eluting stents, the EXCELLENT (Efficacy of Xience/Promus versus Cypher to rEduce Late Loss in stENT) trial aimed to assess the safety and efficacy of an EES to a SES.

“EES has been shown to be superior to paclitaxel-eluting stents with regard to angiographic and clinical endpoints,” said the trial’s principal investigator, Hyo-Soo Kim MD, PhD, of the Seoul National University Hospital, in Seoul, Korea. He noted that “SES have been known to be the most efficacious DES regarding inhibition of neointima and lumen loss.”

The EXCELLENT trial enrolled 1,443 patients with evidence of MI and 50 percent stenosis and randomized them at a 3:1 ratio to receive either a Xience (Abbott Vascular) / Promus (Boston Scientific) EES (n=1,079) or a Cordis CypherSelect SES (n=364).

The researchers used in-segment late lumen loss as the primary endpoint of the study and also looked at the composite rates of cardiac death or MI. Additionally, Kim and colleagues reported the rates of target lesion revascularization (TLR), target lesion failure and stent thrombosis.

“The most important feature of this trial is the high prevalence of diabetes of more than 40 percent,” said Kim.  Additionally, the number of patients on GP IIb/IIIa inhibitors at the time of the trial was less than 2 percent, what Kim called “an unusual phenomenon."

To evaluate late lumen loss, the researchers performed an analysis of almost 1,200 lesions. Angiography showed that in-stent late loss in the EES arm compared with the SES was 119 mm versus 115 mm. Additionally, late in-segment lumen loss was reported to be 100 mm in the EES arm compared with 50 mm in the SES arm. Kim said that the differences in these numbers were not statistically significant. “EES is not inferior to SES in terms of late loss.”

The researchers found that use of the SES showed higher rates of cardiac death and MI when compared to EES at 12 months, 1.9 percent versus 1.5 percent, respectively. The rates for TLR at 12 months were 2.4 percent for the EES arm compared to 1.7 percent for the SES arm.

Target lesion failure occurred at a rate of 3 percent in patients who received the SES compared with a rate of 3.7 percent in patients who received the EES. Comparatively, the rates of stent thrombosis were higher in the SES group when compared to the EES group, 0.8 percent versus 0.4 percent, respectively.

Kim and colleagues also adjusted for MI and assessed pre-procedural rates of MI and spontaneous MI. The rates of spontaneous MI for EES and SES were 0.4 percent and 0.8 percent respective, what Kim noted to be a “very interesting finding,” but not statistically significant. However, he said that these numbers did show a trend of lower incidence rates of MI with EES.

At one-year, Kim noted that the rates of cardiac death were reported to be 0.7 percent in the EES group compared to 1.1 percent in the SES arm.

“The efficacy of EES was non-inferior to SES in inhibiting late loss at nine months and clinical events at 12 months,” said Kim

“Tendency of higher late-loss in EES than SES may lead to the intriguing reciprocal trend between soft versus hard endpoints: higher incidence of TLR but lower incidence of death, MI or stent thombosis.”

Future studies are needed to confirm the results of this trial, Kim concluded.