Authors:
R. B. Aramant, M. J. Seiler, H. M. Petry, P. Green, D. Pidwell, & N. D. Radtke
Summary:
Purpose - In a Phase II clinical trial, the efficacy and safety of transplantation of sheets of fetal retina together with its retinal pigment epithelium (RPE) was investigated in age-related macular degeneration (AMD) and retinitis pigmentosa (RP) patients.
Methods - In a nonrandomized trial, four AMD and six RP patients (vision: light perception to 20/320) were transplanted in one eye with a sheet of freshly dissected fetal retina together with its RPE. Patients were clinically observed for signs of rejection by fundus exams and fluorescein angiograms. Visual acuity testing by Early Treatment Diabetic Retinopathy Study (EDTRS) was the main outcome measurement method. Several patients were tested by a Scanning Laser Ophthalmoscope, multifocal ERG or Microperimetry. Most tissue donors and recipients were tissue typed for MHC antigens. The follow-up time was one year. Seven of the patients were continually followed up between 2 and 6 years.
Results - None of the patients had electrophysiologically measurable responses. At one year after transplantation, three RP and four AMD patients showed improved EDTRS visual scores; one RP patient remained the same and two decreased. One RP patient’s vision improved from 20/800 to 20/160 and was maintained at 20/200 for 5 years. At six years, the patient had 20/320 in the surgery eye, but the non-surgery eye had deteriorated to hand motion vision. No immunological match was seen between donor and host but no rejection was observed clinically.
Conclusion - Seven patients showed improved visual acuity at one year. Several patients maintained improved vision for several years. These results give evidence of the safety and beneficial effects of retinal transplantation and are supported by the many positive research results in animal retinal degeneration models.
Source:
Presented at Neuroscience 2009, the annual meeting of the Society for Neuroscience. Scientific Presentation: Wednesday, Oct. 21, 4–5 p.m., South Hall A