In January 2005, the oversight responsibility of the Post-Approval Studies Program was transferred to the Division of Epidemiology (DEPI) of the Office of Surveillance and Biometrics (OSB)/Center for Devices and Radiological Health (CDRH).
The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a premarket approval (PMA) application, protocol development product (PDP) application, or humanitarian device exemption (HDE) application. The program helps ensure that well-designed post-approval studies (PAS) are conducted effectively and efficiently and in the least burdensome manner.
CDRH has established an automated, internal tracking system that efficiently identifies the reporting status of active PAS studies ordered since January 1, 2005 based on study timelines incorporated in study protocols and agreed upon by the CDRH and applicants. This system represents CDRH's effort to ensure that all PAS commitments are fulfilled in a timely manner.
In addition, CDRH launched this publicly available webpage to keep all stakeholders informed of the progress of each PAS. The webpage displays general information regarding each PAS, as well as the overall study status (based on protocol-driven timelines and the adequacy of the data) and the applicant's reporting status for each submission due.
Julie Unger
Project Manager, Post-Approval Studies Program
Food and Drug Administration
10903 New Hampshire Ave
WO66-4206v
Silver Spring, MD
20993-0002
The study population is comprised of patients with radiographic
confirmation of at least moderate degenerative spinal
stenosis with constriction of the central spinal canal of one or two adjacent segments in the region L1 to L5.
Sample Size
The sample size is 230 patients. There will be 115 patients in
each group. There will
be 115 patients with decompression surgery and without Coflex, and 115 patients with decompression surgery and the Coflex.
Data Collection
The primary endpoint is improvement of Oswestry Low Back
Pain Disability Index (ODI) after 24 months
compared to control group.
Secondary endpoints encompass:
-Superior improvement of the Visual Analog Scale (VAS) for low back pain (on the 100
mm scale) within 24 months compared to control, group.
-Leg pain (Measurement via a 100 mm VAS)
-Zurich Claudication Questionnaire (ZCQ). This is a self rating questionnaire designed to assess symptom severity, physical functional status and patient satisfaction
-Assessment of significant migration of the implant or the complete expulsion
(significant is defined > 5 mm)
-Neurological status (assessment of the maintenance of the improvement after surgery
throughout the study duration)
- Walking distance test on a treadmill (assessment of improvement in walking distance)
Followup Visits and Length of Followup
Patients will be followed for 2 years.
Patients will be evaluated pre-operatively, and at 3, 12
