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 -LTME- Study is designed to further evaluate the safety of the participants of IMT-002
at 84 and 96 months post-implantation of the IMT. The IMT-002 was the pivotal clinical trial that provided 24-month safety and efficacy data for patients with bilateral moderate to severe central vision impairment due to age-related macular degeneration treated with the telescope implant. A number of patients enrolled in Protocol IMT-002 have been followed through 60 months. The proposed post-approval study is to follow these patients through 8 years post-surgery. The planned study is a prospective, observational cohort, open label, single group study of patients who participated in the IMT-002 and the IMT-002-LTM trials regardless of successful telescope implantation. These subjects will be re-contacted and asked to participate in this study.
Study Population Description
Patients who participated in the IMT-002 trial will be contacted and asked to participate in
this study provided they are able to understand and comply with the clinical study and provide informed consent. Inclusion criteria for patients participating in the IMT-002 trial were: Patients with bilateral, stable, untreatable central vision disorders (untreatable AMD or Stargardt-s macular dystrophy) as determined by fluorescein angiography, and cataract. Patients must have distance BCVA between 20/80 and 20/800, and adequate peripheral vision in one eye (the non-implanted eye) to allow navigation. Patients must achieve at least a five letter improvement on the ETDRS chart in the eye scheduled for surgery, with the external telescope. The planned operative eye must have an anterior chamber depth of at least 2.5mm. Patients must be available for the study duration of approximately 24 months and be willing to attend all visits for training and evaluation. Patients must be alert, mentally competent, and able to understand and comply with the requirements of the clinical trial, and be personally motivated to abide by the requirements and restrictions of the clinical trial. Patients must be able to provide voluntary informed consent. Patients must be at least 55 years of age. Patients must sign and be given a copy of the written Informed Consent form.
The sponsors anticipate a cohort of approximately 70 IMT-002 subjects enrolling at approximately 20 participating
sites in this protocol.
The clinical parameters to be evaluated at study visits in both eyes are: Best spectacle-corrected distance
visual acuity (BSDVA) with ETDRS chart Slit lamp examination Fundus examination by indirect ophthalmoscopy Intraocular pressure Adverse events Corneal endothelial cell density in the intraocular telescope operated eye
Followup Visits and Length of Followup
Subjects will be examined at the time of entry into the study, and then will
return for evaluation on the 84-month and 96-month anniversaries dated from the original surgery performed in the IMT-002 study. This schedule of visits is as follows: Enrollment Required only if patient presents more than 3 months before or after the 84-month visit 84 Months (+/- 3 months) 96 Months (+/- 3 months)
Up to 3 years
Final Study Results
Actual Number of Patients Enrolled
Actual Number of Sites Enrolled
Patient Followup Rate
Final Safety Findings
The cohort that went to the LTME study and the cohort without going to the
LTME study showed similar result in terms of ECD change and adverse events.
Mean ECD was somewhat lower at the last available visit prior to LTME enrollment for subjects participating in study LTME, 1575 cells/mm2, compared to subjects not participating in LTME, 1719 cells/mm2
With respect to ocular adverse events of interest, there were no reports of persistent vision impairing corneal edema, no reports of corneal transplantation, no reports of retinal detachment, no reports of device explant, and no reports of device malfunction in LTME subjects during the period of the LTME study.
Decrease in BCDVA greater than 2 lines from IMT-002 pre-surgery baseline in the telescope- implanted eye was observed in 7 subjects (14%); 2 (4%) were reported as severe, 2 (4%) as moderate, and 3 (6%) as mild. Decrease in BCDVA was reported as related to the device in 3 of the subjects (6%), unlikely to be related in 3 (6%) and not related in 1 (2%). It is noteworthy that a decrease in BCDVA greater than 2 lines from the IMT-002 baseline was reported in 14 non- implanted eyes of the LTME subjects (29%). Thus, a loss of BCDVA >2 lines occurred in twice as many fellow eyes as in telescope implanted eyes.
Ocular hypertension was reported in 1 subject (2%); severity was rated as mild and was reported to be device related. There was no report of telescope dislocation, choroidal neovascularization, endophthalmitis, or retinal vascular occlusion during the LTME study in intraocular telescope implanted eyes. One (1) subject (2%) was hit in the telescope implanted eye by a tree branch while tilling his garden; the event was rated as severe and was related to the device.
Final Effectiveness Findings
Study Strengths and Weaknesses
The study was an extended follow-up study of the IDE study cohort. The final follow-up
rate was 96% (49/51). Due to the advanced age of the patients, the delay in approval of the PAS protocol and the associated time constraints, and the fact that many sites chose not to participate, the PAS study had only a small number (i.e., 49 patients in the device group) of the subjects who completed the LTME study and data were almost exclusively from a single study visit. This may present a limitation of the data in terms of the generalizability of the study results.