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U.S. Department of Health and Human Services

Post-Approval Studies (PAS)

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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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OSB Lead-Coflex Long-Term PAS

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Study Status Completed
Application Number P110008 / PAS001
Date Current Protocol Accepted 04/23/2013
Study Name OSB Lead-Coflex Long-Term PAS
General Study Protocol Parameters
Study Design Randomized Clinical Trial
Data Source New Data Collection
Comparison Group Concurrent Control
Analysis Type Analytical
Study Population Adult: >21
Detailed Study Protocol Parameters
Study Design Description Randomized clinical trial
Study Population Description The study population is comprised of patients who received the device during the IDE or controls that underwent Anterior Cervical Decompression and Fusion (ACDF) during the IDE

Sample Size A total of 191 coflex and 104 fusion patients comprise the sample size.

Data Collection The following criteria will be used to evaluate CCS at each post year 2 follow-up point including at year 5. These are the same as used for the two year study only modified to accommodate the longer-term follow-up. For the year 5 endpoint, these are:

Improvement of at least 15 points in the Oswestry Low Back Pain Disability Index (ODI) at 5 years compared to baseline;

No reoperations, revisions, removals, or supplemental fixation;

No major device-related complications, including but not limited to permanent new or increasing sensory or motor deficit at 5 years; and

No epidural steroid injections in the lumbar spine.

In addition to the principal endpoint of survivorship, information on the following efficacy outcomes will be assessed:

Oswestry Disability Index (ODI)

Zurich Claudication Questionnaire (ZCQ)

Leg (right, left) Pain Visual Analog Scale

(VAS) (100mm scale)

Back Pain Visual Analog Scale (VAS) (100mm scale)

Quality of Life (SF-12)

Neurological Status

In addition, each component of the composite clinical success will be used to evaluate coflex® device performance in absolute terms and relative to fusion control, including overall device survival.

The anterior/posterior and lateral radiographs will be assessed for evidence of:



Range of motion and translation in flexion/extension, at the implanted and adjacent level(s) as measured on lateral standing flexion/extension films.

Adjacent level breakdown

Radiographic Observations: Fractures, Heterotopic Ossification, etc.

Patients with an unresolved spinous process fracture at 24 months, observed via independent radiographic assessment, will be subjected to a CT scan at 5 years to determine if the spinous process has healed, pending patient and IRB approval.

Follow-up Visits and Length of Follow-up 5 years.

Patients in the long-term follow-up study will be asked to

return for follow-up evaluations annually (± 4month) at 36,

48 months, and 60 60 months post-surgery. The follow-up evaluations will include assessment of complications, administration of the Oswestry Disability Index (ODI), Leg (right, left, max) and Back Pain

VAS, Zurich Claudication Questionnaire (ZCQ), and SF-12, and radiographic evaluation.

Interim or Final Data Summary
Actual Number of Patients Enrolled 207 in investigation device group and 107 controls
Actual Number of Sites Enrolled 21
Patient Follow-up Rate Investigational device group: 90.7%

Control group: 86.0%
Final Safety Findings No evidence raising serious concerns was found. The 60-month device failure rates are 3.6% and 2.4% for the investigational device group and controls (fusion), respectively. The results are similar when comparing one level procedure and two level procedures.
Final Effect Findings Overall success outcomes including the FDA-defined criteria were met at the end of

60 months. The composite clinical success (CCS) at 60 months were 49.5% and

44.0% (p=0.385) for the investigational device group and the controls, respectively. The results were similar when comparing one level procedure and two level procedures. Other outcomes, including Improvement of at least 15 points in ODI at Month 60 compared to baseline, No reoperation or epidural, No reoperations, revisions, removals, or supplemental fixation, No epidural injection at any lumbar level up to and including the Month 60 visit, No persistent2 new or increasing

sensory or motor deficit at 60 months, No persistent new or increasing sensory deficit at 60 months, and No persistent new or increasing motor deficit at 60 months, were all comparable between coflex and the fusion controls.

Study Strengths & Weaknesses This Extended Follow-Up study was capable of demonstrating comparable outcomes between coflex and fusion, as well as between one level and two level coflex procedures. However, the data are only so far available from the subjects in the IDE study, which may not be

necessarily repetitive of the real world evidence.

Recommendations for Labeling Changes No labeling change is recommended, since all of the observed complications have already been listed in the product labeling and no unusually higher rates of AEs and complications have been observed in the PAS.

OSB Lead-Coflex Long-Term PAS Schedule

Report Schedule
Date Due
FDA Receipt
Applicant's Reporting Status
six month report 04/17/2013 07/05/2013 Overdue/Received
one year report 12/01/2013 02/20/2014 Overdue/Received
18 month report 04/17/2014 06/02/2014 Overdue/Received
two year report 10/17/2014 10/20/2014 Overdue/Received
three year report-Final Report 11/17/2015 01/14/2016 Overdue/Received

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

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