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U.S. Department of Health and Human Services

Post-Approval Studies (PAS) Database

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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.

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LIBERATE Extension Study

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Study Status Progress Adequate
Application Number P180002 / PAS001
Date Current Protocol Accepted 01/28/2019
Study Name LIBERATE Extension Study
General Study Protocol Parameters
Study Design Prospective Cohort Study
Data Source New Data Collection
Comparison Group Device Subjects Serve as Own Control
Analysis Type Descriptive
Detailed Study Protocol Parameters
Study Design Description This is a multi-center, prospective, single-arm cohort study to evaluate long-term safety and long-term effectiveness in the continued follow-up of the premarket cohort for the LIBERATE Pivotal Trial.
Study Population Description Subjects who were previously implanted with the Zephyr Endobronchial Valve System and participated in the LIBERATE Pivotal Trial i.e. initial cohort and crossover subjects.
Sample Size Approximately 142 subjects are available for extended follow-up
Data Collection Effectiveness Endpoint: FEV1

Safety Endpoint: Evaluation of adverse events, summarized by seriousness, severity, and relatedness.

Follow-up Visits and Length of Follow-up Follow-up is planned for five years from the date of implant procedure
Interim or Final Data Summary
Interim Safety Information Interim analysis was conducted after 1 year follow up: FEV1 percent change was 17% from baseline
Actual Number of Patients Enrolled 128
Actual Number of Sites Enrolled 22
Patient Follow-up Rate 128 subjects enrolled

115 completed 1 year follow up (90%)

93 completed 2 year follow up (73%)

79 completed 3 year follow up (62%)

53 completed 4 year follow up (41%)

26 completed 5 year follow up (20%)
Study Strengths & Weaknesses Results demonstrate similar adverse event rate and durable benefit as initial study. Population is >90% Caucasian which may limit the applicability of the results.

LIBERATE Extension Study Schedule

Report Schedule
Date Due
FDA Receipt
Applicant's Reporting Status
six month report 12/28/2018 12/21/2018 On Time
one year report 06/29/2019 06/28/2019 On Time
two year report 06/28/2020 06/25/2020 On Time
three year report 06/28/2021 06/28/2021 On Time
four year report 06/28/2022    

Contact Us

Mandated Studies Program
Food and Drug Administration
10903 New Hampshire Ave.
Silver Spring, MD 20993-0002
Email: MandatedStudiesPrograms@fda.hhs.gov

Additional Resources