The DAPT Study - A prospective, multi-center, randomized, double-blind trial to assess the effectiveness and safety of 12 versus 30 months of dual antiplatelet therapy (DAPT) in subjects undergoing percutaneous coronary intervention (PCI) with either drug-eluting stent (DES) or bare metal stent (BMS) placement for the treatment of coronary artery lesions.

Summary

20,645 subjects will be enrolled at up to 219 US and other clinical study sites around the world. Approximately 60% of sites will be in the U.S. and Canada. Enrollment in the study will be limited to 1,000 subjects at any single site. There will be about 500 subjects enrolled at UTSW. 15,245 subjects will receive PCI with DES and 5,400 will receive PCI with BMS. Given the observational nature of the study, it is a possibility that some sites will exclusively use only one of the study thienopyridines or a limited selection of DES type.

After index procedure, all subjects will take a daily dose of open label active drug (clopidogrel or prasugrel) through 12 months post index procedure and then, if eligible and randomized, they will receive the same drug that they were taking at the time of randomization or corresponding placebo in
a blinded fashion for daily administration through 30 months.

Eligible subjects will be randomized to 18 months of active treatment or placebo 12 months after index
Procedure. Randomized subjects will receive either active drug or placebo identical in appearance to the active drug.

The treatment groups are:
1. Continue thienopyridine treatment for an additional 18 months along with continued aspirin use
(30 m DAPT Arm)
2. Placebo treatment for an additional 18 months along with continued aspirin use
(12 m DAPT Arm)

Randomization will be stratified by site, stent type, subject complexity at baseline and thienopyridine drug. Following randomization, subjects will be assigned blinded study medication (thienopyridine or placebo). All subjects will be recommended to take aspirin at the dose directed by the investigator.

Subjects who are randomized to receive blinded active drug, will receive the same thienopyridine
(clopidogrel or prasugrel) that they were taking at the time of randomization. All subjects should
also receive a daily dose of aspirin 75-162 mg administered concomitantly with study drug.

Subjects randomized to receive 12 months of thienopyridine will receive a daily dose of placebo for 18
months and continue with aspirin therapy. Use of open label thienopyridine will be at the discretion of the treating physician after month 33.

Subjects randomized to receive 30 months of thienopyridine will receive a daily dose of active drug for 30 months and continue with aspirin therapy. Use of open label thienopyridine will be at the
discretion of the treating physician after month 33.

The 12 month visit window has been extended to 330-390 days post index procedure.

All enrolled subjects will be followed for the full 33 months regardless of whether they are randomized.

Participant Eligibility

Subject must meet all of the following criteria to be eligible for treatment in the study:
1. Subject is > 18 years of age (by at least 1 day. [For example if someone was turning 18 today, he/she would have to wait until the next day to be enrolled]).
2. Subjects undergoing percutaneous intervention with stent deployment (or has w/in 24 hours).
3. Subjects without known contraindication to dual antiplatelet therapy for at least 30 months after enrollment and stent implantation.
4. The subject has consented to participate and has authorized the collection and release of his medical information by signing the “Patient Informed Consent Form”. The informed consent will be valid for the duration of the trial or until the subject withdraws.

Randomization Inclusion Criterion at 12 months
Subject must meet the following criterion to be eligible for randomization in the study:
1. Subject is “12 Month Clear”.

“12 Month Clear”
This population consists of subjects enrolled in the study who are free from death, MI, stroke,
repeat coronary revascularization, major bleeding – “severe” or “moderate” by GUSTO classification, and ST 12 months after stent implantation and who are compliant with 12 months of DAPT following stent implantation.