Abstract
Purpose:
To evaluate the visual acuity (VA), central macular thickness (CMT) and intervals between two intravitreal treatments (IVTs) changes in patients first being switched from ranibizumab (RBZ) to aflibercept (AFL) and secondly switched back to RBZ for some cases.
Methods:
Retrospective review of 37 nAMD patients (37 eyes), from 3 french centers, treated with at least six previous IVTs of RBZ according to a treat-and-extend regimen. Outcome variables include VA, measured CMT on OCT and intervals between two IVTs before and after medication changes, 6 months after the switch and 6 months after the switch back.
Results:
37 eyes from 37 patients with wAMD were switched from RBZ to AFL. The mean pre-switch to AFL duration was 40,7 months and the mean number of injections was 34,7. Treatment frequency was unchanged with a 47 mean days between IVTs prior to conversion to AFL compared with 46 days after the switch (p=0,778). There was no effect on VA improvement after the switch to AFL (p=0,959). Switch to AFL was associated with transient improvement in CMT from 326 to 294μm (p=0,940) but CMT increased over time (308μm after 6 IVT). In the subgroup of patients switched back to RBZ (n=11), interval treatment decreased with a 46 mean days before the return to RBZ and a 37 mean days after (p=0,07), CMT changed from 318 to 307μm (p=0,732) and no effect on VA improvement was seen (p=0,959).
Conclusions:
Within the 6 months follow-up period after the switch to aflibercept, most of patients showed an initial improvement on CMT, but this change decreased over time. In our population, visual acuity and injection frequency remained unchanged after the switch to aflibercept in a treat and extend therapy. For patients who were switched back to ranibizumab the interval treatment was decreased by 9 days. Due to the small sample size, results must be interpreted with caution.