Abstract
Purpose :
Eyes with limited clinical response to intravitreal Ranibizumab for nAMD demonstrate significant structural and functional improvement after conversion to intravitreal Aflibercept. Limited large cohort data exists on the long-term effects of switching therapies. This retrospective observational study investigated the changes in best corrected visual acuity (BCVA), central retinal thickness (CRT) and resolution of macular fluid in Ranibizumab-resistant nAMD patients up to three years after switching therapies.
Methods :
Inclusion criteria were eyes with nAMD that had a minimum of six Ranibizumab injections prior to switching to Aflibercept and a minimum of twelve months’ follow-up after switching. Aflibercept regimens included a pro re nata (PRN) regime or a loading dose followed by PRN regime. Primary outcome measures were BCVA, CRT and time taken to achieve first resolution of macular fluid. Data was collected from electronic patient records (Medisoft Ltd) and statistical analysis performed to compare outcomes at different time points.
Results :
Of the 235 eyes that met the inclusion criteria, eight were excluded due to incomplete data. Of the remaining 227 eyes (202 patients), 29.2% were male and 70.8% were female. with mean age of 83.0 years (79.0-88.0). Mean follow-up time was 29.5 months (28.0-33.0). Interquartile ranges are shown in brackets.
Mean BCVA at point of switching, at one year and at latest follow-up in LogMAR was 0.47 (0.30-0.60), 0.38 (0.20-0.60) and 0.45 (0.20-0.70), respectively. Significant improvement was demonstrated when comparing BCVA at point of switching with follow-up at one year (p<0.001).
Mean CRT at point of switching, at one year and at latest follow-up in micrometres was 286 (239-316), 259 (221-286) and 246 (212-269), respectively. Significant improvement was demonstrated when comparing CRT at point of switching with follow-up at one year and at latest follow-up (p<0.0001, p<0.0001).
Initial resolution of macular fluid was achieved during follow-up in 77.1% eyes at a mean of 4.7 months (2.0-6.0).
Conclusions :
Resolution of macular fluid was achieved at some point in the majority of eyes. Both CRT and vision improved significantly when switching therapy, but only the effect on CRT was maintained over a long period of time.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.