• Decrease font size
  • Return font size to normal
  • Increase font size
U.S. Department of Health and Human Services

Post-Approval Studies (PAS)

  • Print
  • Share
  • E-mail

The FDA has the authority to require sponsors to perform a post-approval study (or studies) at the time of approval of a premarket approval (PMA), humanitarian device exemption (HDE), or product development protocol (PDP) application. Post-approval studies can provide patients, health care professionals, the device industry, the FDA and other stakeholders information on the continued safety and effectiveness (or continued probable benefit, in the case of an HDE) of approved medical devices. This database allows you to search Post-Approval Study information by applicant or device information.

Learn more...


OSB Lead-Extended Followup of the EXPERT CTO Study

Suggest Enhancement / Report Issue | export reports to excelExport to Excel
Study Status Completed
Application Number P110019 S066/ PAS001
Date Current Protocol Accepted 03/03/2017
Study Name OSB Lead-Extended Followup of the EXPERT CTO Study
General Study Protocol Parameters
Study Design Prospective Cohort Study
Data Source New Data Collection
Comparison Group Historical Control
Analysis Type Descriptive
Study Population Adult: >21
Detailed Study Protocol Parameters
Study Design Description This study is the continued follow-up of the premarket cohort. It is a prospective, multi-center, single-arm study.
Study Population Description All patients in whom recanalization and predilatation of CTO are completed and the study stent(s) (XIENCE V and/or XIENCE PRIME) is inserted into the coronary guiding catheter.

Sample Size A total of 250 patients were enrolled at 20 sites in the United States, with the intention-to-treat population consisting of 222 patients. There are 205 patients available with 1-year follow-up.

Data Collection The following outcomes will be reported annually through 5 years:

XRate of Major Adverse Cardiac Events (MACE), defined as a composite of death, Myocardial Infarction (MI), or clinically- driven Target Lesion Revascularization (TLR), and individual MACE components

¿XTarget Lesion Failure (TLF), defined as a composite of cardiac death, target vessel-related MI, and clinically-driven TLR and individual TLF components

¿XTarget Vessel Revascularization (TVR) and clinically-driven TVR

¿XTarget Vessel Failure (TVF), defined as a composite of cardiac death, target vessel-related MI, and clinically-driven TVR

¿XOccurrence of stent fracture at target lesion, as assessed by fluoroscopy in patients undergoing clinically-driven angiographic follow-up at any time during the 5-year study period (the same angiographic core lab will continue to be utilized throughout the five-year follow-up period)

¿XStent thrombosis according to Academic Research Consortium

(ARC) criteria (all, definite, definite/probable, probable, possible): acute, subacute, late, very late and accumulative rates

Follow-up Visits and Length of Follow-up 3 years post-procedure
Interim or Final Data Summary
Actual Number of Patients Enrolled 202 subjects available at 1 year for long term follow- up
Actual Number of Sites Enrolled 20
Patient Follow-up Rate 84.7% (171/202) at 4 years
Final Safety Findings The EXPERT CTO clinical trial met its primary endpoint. The stent related endpoint result of 1- year MACE [composite of death, myocardial infarction (MI) or clinically driven target lesion revascularization (CD-TLR)] rate was significantly lower than the pre-specified performance goal (PG) of 24.4% in both the intent-to-treat (ITT) population (18.5%, 1 sided UCL= 23.4%, p

=0.0248) and the per protocol (PP) population (8.2%, 1 sided UCL = 12.3%, <.0001).

The key secondary endpoints based on the ITT population through four (4) years are as follows: MACE (death, MI or CD-TLR) per ARC 31.6% (62/196)

per protocol 22.4% (44/196)

Target Lesion Failure (cardiac death, Target vessel-MI or CD-TLR) per ARC 24.1% (45/187)

per protocol 17.2% (32/186)

Target Vessel Failure (Cardiac death, Target vessel MI or CD-TVR) per ARC 26.2% (49/187)

per protocol 19.4% (36/186)

Death 10.5% (20/191)

Cardiac Death 5.5% (10/181)

All MI per ARC 20.3% (37/182)

Target Vessel MI (TV-MI) per ARC 15.5% (28/181)

All TLR (target Lesion revascularization) 11.9% (21/177)

CD-TLR 11.3% (20/177)

All TVR (target vessel revascularization), inclusive of target lesion)

13.6% (24/177)

All TVR (non-target lesion) 2.9% (5/172)

Stent Thrombosis (Definite/probable) 1.7% (3/174)

Study Strengths & Weaknesses Strength: The EXPERT CTO study was a prospective, open-label, multicenter study.

The study achieved a follow-up rate greater than 80% at 4 years. An independent clinical event committee performed adjudication of the safety endpoints including all cases of death, Q-wave myocardial infarction (QMI), non Qwave MI (NQMI), stent thrombosis, target lesion revascularization and target vessel revascularization.

Weakness: There is no formal hypothesis testing for the long term (4 year) study outcomes. The study is limited by the small sample size.

Study Strengths and Limitations: The EXPERT CTO study was a prospective, open-label, multicenter study. All event adjudications were performed by an independent Clinical Event Committee (CEC) with 100% site-reported adjudicable events being source-verified. This study provides important information on clinical outcomes in patients with chronic total occlusions treated with the XIENCE family of stents. The study is limited by being a small study with no head-to-head comparison with other DES platforms. In addition, due to the small population size, subgroup analysis can at best be considered exploratory.

Recommendations for Labeling Changes Labeling change is recommended to reflect the long term data from the post-approval study. The labeling change should include a new section on the label showing a summary of the post Approval mstudy methods (including study objectives, design, population, number of enrolled sites/subjects, key endpoints, follow –up visits etc.), results and study strengths and limitations.

OSB Lead-Extended Followup of the EXPERT CTO Study Schedule

Report Schedule
Date Due
FDA Receipt
Applicant's Reporting Status
one year report 10/03/2015 10/07/2015 Overdue/Received
two year report 10/02/2016 09/30/2016 On Time
Final Report 06/30/2017 06/26/2017 On Time

Contact Us

Julie Unger
Project Manager, Post-Approval Studies Program
Food and Drug Administration
10903 New Hampshire Ave
WO66-4206v Silver Spring, MD

Phone: (301) 796-6134
Fax: (301) 847-8140

Related Links