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.
The sponsor has created a registry-based study that will include all patients who have received
an AUS 800 or AUS 800 with IZ at a US-based site subsequent to October 13, 2006. It is a passive surveillance system where information is voluntarily submitted to AMS by the implanting physician and is tied to credit for new devices under warranty. The purpose of the registry is to evaluate the long-term performance of the AUS 800 compared to the AUS 800 with IZ by evaluating infection, mechanical component and system failures and surgical revision. The study hypothesis is that there is equal survival time (based on device replacement due to infection or mechanical failure) for IZ impregnated versus unimpregnated devices.The objective of this post-approval registry is to evaluate the long term performance of the AMS 800 against the long term performance of the AMS 800 with InhibiZone as it relates to rate of infection, mechanical component or system failures and surgical revision rates.
Study Population Description
Study population is as per device indication. This device is used to treat urinary incontinence
due to reduced outlet resistance (intrinsic sphincter deficiency) following prostate surgery.
All comers registry
Primary endpoint is device replacement surgery
Followup Visits and Length of Followup
There are no follow up visits in this study; the entire study will include 5
years of follow up for each patient.
Final Study Results
Actual Number of Patients Enrolled
Actual Number of Sites Enrolled
Patient Followup Rate
There was no formal follow쳌]up in this registry쳌]based study. The post쳌]approval study included patients who
were implanted with the AMS 800 device between October 14, 2006 and July 31, 2012 and those receiving revisions on a previously implanted AMS 800 device through July 31, 2012.
Final Safety Findings
Infection Free Rates For the overall system, the infection free rates were not significantly different between
the Inhibizone (IZ) and non쳌]Inhibizone (non쳌]IZ) groups in the Original surgery group (98.26% vs. 98.22%) and in the Revision surgery group (96.77% vs. 96.48%). For specific components, there were also no statistically significant differences in infection free rates between the IZ and non쳌]IZ devices in both Original and Revision surgery groups.
Mechanical Malfunction Free Rates For the overall system, in the Original Surgery Group, the IZ group had a significantly lower malfunction free rate than the non쳌]IZ group (93.47% vs. 95.22%, P=0.003). However, in the Revision Surgery Group, the malfunction free rate was not significantly different between the IZ and non쳌]IZ groups (92.85% vs. 92.81%, P>0.05).
For the Components analysis, in the Original Surgery Group, the difference in malfunction free rates for the Pump and Balloon were not statistically significant, but the differences in malfunction free rates for the cuff [IZ 98.40% vs. non쳌]IZ 99.04%, P=0.007] and the Not Specified Component [IZ 97.11% vs. non쳌]IZ 98.16%, P=0.03] were statistically significant. In the Revision Surgery Group components analysis, there were no statistically significant differences in malfunction free rates.
Final Effectiveness Findings
For both the Original Surgery Group and the Revision Surgery Group, the 5쳌]year revision free
rate from any cause was higher in the IZ group compared to the non쳌]IZ group but the difference was not statistically significant [Original Surgery Group: (IZ 78.94% vs. non쳌]IZ 77.79%; difference=1.15%; log rank test P= 0.191); Revision Surgery Group: (IZ 73.85% vs. non쳌]IZ 72.04%; difference=1.81%; log rank test P= 0.933)].
Study Strengths and Weaknesses
Strengths An all쳌]comers Registry쳌]based study with large, representative study sample
Weaknesses There is no formal follow쳌]up plan, which
may contribute to bias and underreporting of events. In addition, the database does not record events (e.g., infection) that are successfully treated without a surgical explant procedure, i.e., if no implanted system component change occurs or no surgical device adjustment occurs, the study did not record the (infection) event in the database. Therefore, the reported adverse event rates may be lower than the actual rate experienced by participating patients.
Recommendations for Labeling Changes
Labeling change recommended to include long쳌]term safety and effectiveness data from the registry쳌]based study.