Why is this study important?

• Drug-carrier-based sirolimus-eluting stents have theoretical advantages compared to polymer-based zotarolimus-eluting stents.
• The design allows more of the drug to be focused on the vessel wall rather than the vessel lumen. This allows for better drug elution in the complex atherosclerotic pathology found in diabetic patients. Basic science studies suggest this difference may relate to differences in clinical outcomes.
• Drug-carrier-based sirolimus-eluting stents showed superiority compared with polymer-based zotarolimus-eluting stents, after one year of follow-up in patients with diabetes.  

What question was this study supposed to answer?

Was the benefit of drug-carrier-based sirolimus-eluting stents over polymer-based zotarolimus-eluting stents maintained with long-term follow-up to five years?

What did the study show?

• The primary endpoint of the five-year follow-up of these patients was an intention-to-treat analysis of target lesion failure. Target lesion failure was defined as cardiac death, target vessel myocardial infarction (MI), or target lesion revascularization.
• The results reveal a trend in benefit of the primary endpoint with the drug-carrier-based sirolimus-eluting stent at 13.6% versus the polymer-based zotarolimus-eluting stent at 17.4%. This did not reach statistical significance.  There was no difference in safety, with no statistically significant difference in late stent thrombosis between the two groups.
• In addition, when the results were analyzed via the “as treated cohort “, excluding crossovers, use of non-study stents, and no stent placement at all, the benefit of the drug carrier-based sirolimus stent at 13.1% versus the polymer-based zotarolimus stent at 17.0% did reach statistical significance with the p value of 0.049.
• Limitations of the study included low intravascular imaging use and that the outcomes from years 2 through 5 were self-reported.