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.
Surgery consisting of implantation of one (1) GTS100 stent in conjunction with cataract surgery (treatment group)
Surgery consisting of cataract surgery only in subjects randomized to control group in the GC-007 and GC-008 trials and the initial phase of GTS100-PAS2 (control group)
Washout of ocular hypotensive medications at Month 23 (if on medications)
Follow-up through 3 years postoperative
Study Population Description
Males or Females, 22 years of age or older
180 eyes of 180 subjects will comprise the treatment group. In addition, subjects randomized to
cataract surgery only during the initial phase of this trial are included in the total study subject population. Subjects will be enrolled at a minimum of 20 sites and up to 45 sites; it is expected that about 400 subjects or more will undergo screening and baseline exams and operative procedures in order to obtain 180 eyes that received a GTS100 stent in conjunction with cataract surgery.
With estimated rates of 0.03 (3%) for PT and PC at 5 years, a Type I error rate of 5%, a Type II error rate of 20% (i.e., 80% power), a randomization ratio of 1:1, 1-sided testing, a two-group large-sample normal approximation test of proportions, and a ? of 0.05 (i.e., a non-inferiority margin of 0.05 or 5%), the required sample size is 288 subjects (or 144 per group). Due to the age of the study population, it is estimated that the study will have a drop-out rate of 20%.
The primary endpoints will be the occurrence of STAEs. The STAEs include best corrected visual
acuity (BCVA) loss ? 3 lines, endophthalmitis, corneal decompensation, retinal detachment, severe choroidal hemorrhage, severe choroidal detachment, and aqueous misdirection.
Other important ocular adverse events includes increase in intraocular pressure (IOP) of ? 10 mmHg at any time postoperative, and loss of best spectacle corrected visual acuity of ? 2 lines (? 10 letters) postoperative as compared to baseline or best recorded visual acuity measured at any visit postoperative.
Additional safety events of interest include findings from IOP, best spectacle corrected visual acuity (BSCVA), visual field, pachymetry, and specular microscopy measurements, stent dislocation, stent migration, stent obstruction, secondary procedures, such as additional surgical procedures to lower IOP, and findings from slit-lamp, fundus and gonioscopic examinations.
The effectiveness outcomes, although not the primary endpoint of this safety study, are the outcomes of mean diurnal IOP reduction ? 20% vs. baseline IOP without ocular hypotensive medication, and mean diurnal IOP ? 18 mmHg without ocular hypotensive medication, at 24 months. The rate of these effectiveness outcomes will be compared between the treatment and control groups.
Followup Visits and Length of Followup
Visit 1 Screening (day -60 to day -5)
Visit 2 Baseline (after completion
of appropriate medication washout period)
Visit 3 - Operative
Visit 4 6 Hours (+/- 4 hours)
Visit 5 Day 1 (+1 day)
Visit 6 Week 1 (7 +/- 2 days)
Visit 7 Month 1 (4 weeks +/- 7 days)
Visit 8 Month 3 (13 weeks +/- 14 days)
Visit 9 Month 6 (26 weeks +/- 30 days)
Visit 10 Month 12 (52 weeks +/- 30 days)
Visit 11 Month 18 (78 weeks +/- 45 days)
Visit 12 Month 23 (Minimum 4 weeks Prior to Month 24 Visit; 96 to 104 weeks)