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.
Extended follow-up of subjects previously enrolled in Glaukos Study
GC-003; Follow-up through 5 years postoperative
Study Population Description
¿ Inclusion Criteria: Subjects previously enrolled in Glaukos Study GC-003 who are able and willing to
participate in this extended follow-up study;
¿ Exclusion Criteria:
o Subjects previously enrolled in Glaukos Study GC-003 who are not able or willing to participate in this extended follow- up study
o Patients not previously enrolled in Glaukos Study GC-003
Device subjects received the Glaukos iStent in conjunction with
cataract surgery and controls subjects received cataract surgery alone.
Of 290 subjects enrolled in Study GC-003, extended follow-up is
planned on subjects eligible to participate
in this extended follow-up study.
The safety measurement listed in the outline section as:
¿ Postoperative ocular adverse events
¿ Findings from OR medication
use, BSCVA, VF
measurements and pachymetry
¿ Findings from slit-lamp, fundus and gonioscopic measurements
Followup Visits and Length of Followup
5 years postoperative. 2 years from completion of the IDE study
Final Study Results
Actual Number of Patients Enrolled
Actual Number of Sites Enrolled
Patient Followup Rate
Only 42.35% (108/255) enrolled at the beginning of the IDE cohort continuation study. Of those
108 subjects enrolled, 100% of subjects were followed through the fifth year post procedure.
Final Safety Findings
Kaplan-Meier (K-M) analyses for the sight-threatening adverse event rate at 5 years are provided by
randomized groups: all eyes with cataract surgery and iStent versus randomized cataract surgery only. The cumulative Kaplan-Meier probability that a patient experienced a sight-threatening adverse event is 26.0% (95% CI 15.6%, 36.3%) in the randomized cataract surgery with stent group (stent group) and 42.8% (95% CI 27.9%, 57.8%) in the cataract surgery only group (control group). These results indicate that the stent group is non-inferior to the control group (p=0.009). Based on the upper 1-sided 90% confidence limit (CL), the stent group has a lower incidence of sight-threatening adverse events than the control group. Analyses presented for the comparison of all eyes with cataract surgery and iStent versus randomized cataract surgery only provide cumulative Kaplan-Meier probability that a patient experienced a sight-threatening adverse event is 28.5.0% (95% CI 19.6%, 37.4%) in the Overall Cataract Surgery with iStent (stent group) and 42.8% (95% CI 27.9%, 57.8%) in the Randomized Cataract Surgery Only (control group). These results indicate that the stent group is non-inferior to the control group (p=0.015). Based on the upper 1-sided 90% confidence limit (CL),the stent group has a lower incidence of sight-threatening adverse events than the control group.
Final Effectiveness Findings
This study does not include any effectiveness endpoints
Study Strengths and Weaknesses
Strength: The continued IDE study is an observational study with a clinical trial design with
longer term follow-up of safety data.
Weakness: The enrollment rate from the premarket cohort for the eligible subjects is only 42%. The low enrollment rate could introduce bias to the study.
Recommendations for Labeling Changes
As a result, upon completion of the post approval studies with significant clinical findings, labeling
recommended to update the labeling with long-term device performance results regarding safety