Efficacy outcomes and treatment burden of ‘as required’ ranibizumab to ‘Treat and Extend’ aflibercept for neovascular Age - related Macular Degeneration: 12 month pre and post switch analysis in clinical practice.

Abstract

 

Purpose

 

Previous studies studying switch therapy between anti-Vascular Endothelial Growth factor agents are often limited in their short study duration and to a non responsive /recalcitrant population.<br /> We study the efficacy outcomes and treatment burden in a cohort switched from ‘as required’ (prn) ranibizumab to a modified Treat and Extend (T and E) aflibercept when the intention of change was to reduce treatment burden.

 

Methods

 

A retrospective analysis of Visual Acuity (VA), Central Retinal Thickness (CRT) and treatment burden data from all patients switched in October 2013 in teaching hospital medical retina specialist setting. 12 months of follow up before and after switch were required to be included. Mean (SD), paired t-test and repeated measures ANOVA were used to compare the data points. p<0.05 was considered statistically significant.

 

Results

 

177 eyes of 160 patients fulfilled the inclusion criteria. 70% were females with a mean age of 82.7 (SD 7.7) years.<br /> Mean VA decreased from 60.81 (SD 13.84) ETDRS letters 12 months pre switch to 59.18 (SD 15.36) at switch (p=0.019), with further, non-significant decrease to 58.91 (SD 16.36) 12 months post switch (p=0.67). There was an increase in VA one month post switch (59.18 to 60.12 (SD 14.62, p=0.04).<br /> Mean CRT did not significantly decrease from 12 months pre switch 265.69 (SD 76.41) microns to 257 (SD 62.43) at switch (p=0.1), but did do so to 231.10 (SD 43.12) at 12 months post switch (p=<0.001).<br /> Mean number of visits pre switch was 10.97 (SD 2.12), and post switch was 9.47 (SD 2.28, p<0.001). At the end of 12 months post switch, 63.25% were on <8 weeks follow up intervals and 36.7% at 8 weeks and above.<br /> The mean number of injections pre switch was (8.34, SD 2.56) and post switch was (8.50, SD 1.54, p=0.44).

 

Conclusions

 

Switch from 'prn' ranibizumab to T and E aflibercept resulted in a significant reduction in the CRT with stabilisation of the VA post switch with the same number of treatments but with a mean of 1.5 less visits per patient.  

 

Figure 1. The visual acuity and central retinal thickness before and after switch (Time = 0) from as required ranibizumab to Treat and Extend aflibercept.