Scripps Evaluation of Antiplatelet Therapies for Intermediate Duration With the Endeavor Stent (Seaside)
Status:
Completed
Trial end date:
2013-08-01
Target enrollment:
Participant gender:
Summary
Despite the benefit of drug-eluting stents (DES) to reduce the need for repeat
revascularization procedures, concerns regarding late stent thrombosis (ST) have led to
recent guidelines advocating extended prescription of dual antiplatelet therapy (DAPT) with
aspirin and a thienopyridine (clopidogrel or ticlopidine]) beyond that described in the
product labeling. Specifically, an advisory has recommended at least 1 year DAPT following
treatment with DES in patients without contraindications. However, this recommendation was
largely empiric and not based on any trial showing reductions in ST with long-term DAPT, nor
are potential safety differences between DES considered. Further, no study has examined the
balance in potential efficacy with long-term DAPT relative to an increased bleeding risk.
A consistency across clinical trials involving the Endeavor DES has been very low rates of
late myocardial infarction, cardiac death and ST. Unlike other DES, recent studies indicate
that the Endeavor stent may permit more rapid and complete healing over stent struts in
addition to restoring normal blood vessel function. Further, in patients treated with the
Endeavor stent, long-term safety outcomes are similar through 3 years follow-up irrespective
of whether patients were adherent to DAPT for durations of ≤ 6 months, 12 months or 24
months.
In this study, long-term safety and effectiveness will be examined for patients treated with
the Endeavor stent and assigned to DAPT for reduced duration of 6 months. If the study
demonstrates safety and efficacy, it could influence treatment guidelines in favor of an
abbreviated duration of DAPT for patients treated with the Endeavor stent. This would mean
that should a bleeding complication or need or surgery arise less than 12 months post-PCI,
patients treated with the Endeavor stent could stop DAPT after 6 months with reasonable
estimate of safety. Furthermore, it is possible that patients who are currently denied DES
due to known need for elective surgery could be treated with the Endeavor stent in cases
where surgery can be temporarily delayed. Finally, it could be an additional option for
patients who forgo treatment with DES in favor of bare metal stent (BMS) out of fear of
possible bleeding with long-term DAPT.
Finally, it is recognized that not all patients respond the same way to anti-platelet
therapy. Recent studies have indicated that inherited genetic variations in the way the body
metabolizes anti-platelet medications may be important determinants of responsiveness to
thienopyridine therapy, and that such differences may also confer a higher likelihood of
adverse outcome. Patients agreeing to the additional genetic sub-study will have a DNA sample
taken at baseline to test for the presence of such genes related to antiplatelet therapy
metabolism and effectiveness. The results of these tests could help the medical community to
better understand individual variation in response to anti-platelet therapy and the role that
genetics may play in determining the response. It is possible that the information gained
could help physicians tailor DAPT on a patient by patient basis.